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In 2007, astronomers discovered the Cosmic Horseshoe, a gravitationally lensed system of galaxies about five-and-a-half billion light-years away. The foreground galaxy’s mass magnifies and distorts the image of a distant background galaxy whose light has travelled for billions of years before reaching us. The foreground and background galaxies are in such perfect alignment that they create an Einstein Ring.

New research into the Cosmic Horseshoe reveals the presence of an Ultra-Massive Black Hole (UMBH) in the foreground galaxy with a staggering 36 billion solar masses.

There’s no strict definition of a UMBH, but the term is often used to describe a supermassive black hole (SMBH) with more than 5 billion solar masses. SMBHs weren’t “discovered” in the traditional sense of the word. Rather, over time, their existence became clear. Also, over time, more and more massive ones were measured. There’s a growing need for a name for the most massive ones, and that’s how the term “Ultra-Massive Black Hole” originated.

The discovery of the enormously massive black hole in the Cosmic Horseshoe is presented in new research. It’s titled “Unveiling a 36 Billion Solar Mass Black Hole at the Centre of the Cosmic
Horseshoe Gravitational Lens,” and the lead author is Carlos Melo-Carneiro from the Instituto de Física, Universidade Federal do Rio Grande do Sul in Brazil. The paper is available at arxiv.org.

There was a revolution in physics in the late 19th/early 20th century as relativity superseded Newtonian physics and propelled our understanding of the Universe to the next level. It became clear that space and time were intertwined rather than separate and that massive objects could warp spacetime. Even light wasn’t immune, and Einstein gave the idea of black holes—which dated back to John Michell’s ‘dark stars’—a coherent mathematical foundation. In 1936, Einstein predicted gravitational lensing, though he didn’t live long enough to enjoy the visual proof we enjoy today.

Now, we know of thousands of gravitational lenses, and they’ve become one of astronomers’ naturally occurring tools. They exist because of their enormous black holes.

The lensing foreground galaxy in the Cosmic Horseshoe is named LRG 3-757. It’s a particular type of rare galaxy called a Luminous Red Galaxy (LRG), which are extremely bright in infrared. LRG 3-757 is also extremely massive, about 100 times more massive than the Milky Way and is one of the most massive galaxies ever observed. Now we know that one of the most massive black holes ever detected occupies the center of this enormous galaxy.

“Supermassive black holes (SMBHs) are found at the centre of every massive galaxy, with their masses tightly connected to their host galaxies through a co-evolution over cosmic time,” the authors write in their paper.

Astronomers don’t find stellar-mass black holes at the heart of massive galaxies and they don’t find SMBHs at the heart of dwarf galaxies. There’s an established link between SMBHs and their host galaxies, especially massive ellipticals like LRG 3-757. This study strengthens that link.

The research focuses on what’s called the MBH-sigmae Relation. It’s the relationship between an SMBH’s mass and the velocity dispersion of the stars in the galactic bulge. Velocity dispersion (sigmae) is a measurement of the speed of the stars and how much they vary around the average speed. The higher the velocity dispersion, the faster and more randomly the stars move.

When astronomers examine galaxies, they find that the more massive the SMBH, the greater the velocity dispersion. The relationship suggests a deep link between the evolution of galaxies and the growth of SMBHs. The correlation between an SMBH’s mass and its galaxy’s velocity dispersion is so tight that astronomers can get a good estimate of the SMBH’s mass by measuring the velocity dispersion.

However, the UMBH in the Cosmic Horseshoe is more massive than the MBH-sigma e Relation suggests.

“It is expected that the most massive galaxies in the Universe, such as brightest cluster galaxies (BCGs), host the most massive SMBHs,” the authors write. Astronomers have found many UMBHs in these galaxies, including LRG 3-757. “Nonetheless, the significance of these UMBHs lies in the fact that
many of them deviate from the standard linear MBH?sigmae relation” the researchers explain.

LRG 3-757 deviates significantly from the correlation. “Our findings place the Cosmic Horseshoe ~1.5 sigma above the MBH?sigmae relation, supporting an emerging trend observed in BGCs and other massive galaxies,” the authors write. “This suggests a steeper MBH?sigmae relationship at the highest masses, potentially driven by a different co-evolution of SMBHs and their host galaxies.”

This figure from the research shows the relationship between the SMBH mass and the host effective
velocity dispersion. The black solid line represents the relation from previous research in 2016, with dashed and dotted lines showing the 1 sigma and 3 sigma scatter, respectively. Horseshoe is labelled and clearly deviates from established relationship. The other galaxies labelled nearby also contain UMBHs that deviate significantly. Image Credit: Melo-Carneiro et al. 2025.

What’s behind this decoupling of the MBH?sigmae relation in massive galaxies? Some stars might have been removed from the galaxy in past mergers, affecting the velocity dispersion.

LRG 3-757 could be part of a fossil group, according to the authors. “The lens of the Horseshoe is unique in that is at ? = 0.44 and that has no comparably massive companion galaxies — it is likely a fossil group,” they write.

Fossil groups are large galaxy groups that feature extremely large galaxies in their centers, often LRGs. Fossil groups and LRGs represent a late stage of evolution in galaxies where activity has slowed. Few stars form in LRGs so they’re “red and dead.” There’s also little to no interaction between galaxies.

“Fossil groups, as remnants of early galaxy mergers, may follow distinct evolutionary pathways compared to local galaxies, potentially explaining the high BH mass,” the authors write.

LRG 3-757 could’ve experienced what’s called “scouring.” Scouring can occur when two extremely massive galaxies merge and affects the velocity dispersion of stars in the galaxy’s center. “In this process, the
binary SMBHs dynamically expel stars from the central regions of the merged galaxy, effectively reducing the stellar velocity dispersion while leaving the SMBH mass largely unchanged,” the authors explain.

Another possibility is black hole/AGN feedback. When black holes are actively feeding they’re called Active Galactic Nuclei. Powerful jets and outflows from AGN can quench star formation and possibly alter the central structure of the galaxy. That could decouple the growth of the SMBH from the velocity dispersion.

Artist view of an active supermassive black hole and its powerful jets. Image Credit: ESO/L. Calçada

“A third scenario posits that such UMBH could be remnants of extremely luminous quasars, which experienced rapid SMBH accretion episodes in the early Universe,” the authors write.

The researchers say that more observations and better models are needed “to explain the scatter in the ?BH ? sigma e relation at its upper end.”

More observations are on the way thanks to the Euclid mission. “The Euclid mission is expected to discover hundreds of thousands of lenses over the next five years,” the authors write in their conclusion. The Extremely Large Telescope (ELT) will also contribute by allowing more detailed dynamical studies of the velocity dispersion.

“This new era of discovery promises to deepen our understanding of galaxy evolution and the interplay between baryonic and DM components,” the authors conclude.

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Venus differs from Earth in many ways including a lack of internal dynamo driving global magnetosphere to shield potential life from solar and cosmic radiation. However, Venus possesses a dense atmosphere and, in a recent study, planetary scientists conducted simulations of the Venusian atmosphere to determine radiation penetration to the lower cloud layers. Their calculations revealed that the atmospheric thickness provides adequate protection for life at what’s considered Venus’s “habitable zone,” located 40–60 km above the surface.

Venus, the second planet from the Sun, is often called Earth’s “sister planet” because of its comparable size and composition. Yet its environment couldn’t be more different or extreme. It has a thick carbon dioxide atmosphere with sulfuric acid clouds that have created a runaway greenhouse effect, making Venus the solar system’s hottest planet—surface temperatures in excess of 475°C. The Venusian landscape features volcanic plains, mountains, and canyons under atmospheric pressure exceeding 90 times Earth’s. Despite these inhospitable conditions, Venus remains an object of scientific interest, with researchers studying its geology and atmosphere.

Venus

In 2020, scientists found phosphine in Venus’s atmosphere which, on Earth, is mostly made by biological processes or in other words – living things. This discovery was somewhat unexpected and facilitated a fresh look at Venus as a possible home for life. Surprisingly perhaps, Venus does have a “habitable zone” in its clouds about 40-60 km up, where the temperature and pressure aren’t too different from Earth’s. While the planet’s surface is totally uninhabitable, high up in the atmosphere might actually support some kind of microbial life that’s adapted to acidic conditions. A new piece of research has been exploring if the thick Venusian atmosphere would protect any such life that may have evolved or whether intense radiation bathes its habitable zone. 

The spectral data from SOFIA overlain atop this image of Venus from NASA’s Mariner 10 spacecraft is what the researchers observed in their study, showing the intensity of light from Venus at different wavelengths. If a significant amount of phosphine were present in Venus’s atmosphere, there would be dips in the graph at the four locations labeled “PH3,” similar to but less pronounced than those seen on the two ends. Credit: Venus: NASA/JPL-Caltech; Spectra: Cordiner et al.

The research, that was led by Luis A. Anchordoqui from the University of New York has revealed surprising results. The team discovered that despite Venus lacking a magnetic field and orbiting closer to the Sun, the radiation levels in its potentially habitable cloud layer are remarkably similar to those at Earth’s surface. Using the AIRES simulation package (AIRshower Extended Simulations – simulates cascades of secondary particles from incoming high energy radiation) the team generated over a billion simulated cosmic ray showers to analyse particle interactions within Venus’s atmosphere. 

Their findings show that at equivalent atmospheric depths, particle fluxes on Venus and Earth are nearly identical, with only about 40% higher radiation detected at the uppermost boundary of Venus’s habitable zone. This suggests Venus’s thick atmosphere provides substantial radiation shielding that might be sufficient for potential microbial life.

The research suggests that cosmic radiation wouldn’t significantly hinder life in Venus’s cloud layer. Any potential microorganisms that were there would face radiation levels similar to those on Earth’s surface. On Earth, life has found a way across a wide range of environments that span many kilometres, this is known as its life reservoir. Venus doesn’t have such a great reservoir so if radiation were to sterilise the habitable clouds, there’s no equivalent to Earth’s subsurface biosphere that could eventually recolonise the region. This means life needs to persist continuously in its atmospheric habitat without being able to move to other parts of the planet.

Source : The Venusian Chronicles

The post Although it Lacks a Magnetic Field, Venus Can Still Protect With in its Atmosphere appeared first on Universe Today.

The journey to Mars will subject astronauts to extended periods of exposure to radiation during their months-long travel through space. While NASA’s Artemis 1 mission lasted only a matter of weeks, it provided valuable radiation exposure data that scientists can use to predict the radiation risks for future Mars crews. The measurements not only validated existing radiation prediction models but also revealed unexpected insights about the effectiveness of radiation shielding strategies too. 

Space radiation poses one of the most significant health risks for astronauts travelling beyond Earth’s magnetic field. Unlike the radiation from medical X-rays or nuclear sources on Earth, space radiation includes high-energy galactic cosmic rays and solar particle events that can penetrate traditional shielding materials. When these particles collide with human tissue, they can damage DNA, increase cancer risk and weaken the immune system. The effects are cumulative too, with longer missions like a journey to Mars significantly increasing exposure and health risks. 

Artist’s illustration of ultra-high energy cosmic rays

The International Space Station crews receive radiation doses similar to nuclear power plant workers due to a little protection from Earth’s magnetosphere, but astronauts traveling to Mars would face much higher exposure levels during their multi-month journey. NASA estimates that a mission to Mars could expose astronauts to radiation levels that exceed current career exposure limits, making effective radiation shielding one of the key challenges for deep space exploration.

A full-disk view of Mars, courtesy of VMC. Credit: ESA

A paper recently published by a team led by Tony C Slaba from the Langley Research Centre at NASA, they use computer models and data from on-board detectors to assess the health risk to long term space flight. The data is taken from the International Space Station (ISS,) the Orion Spacecraft, the BioSentinel CubeSat and from receivers on the surface of Mars. Collectively this data enables a full mission profile to be modelled for a Martian journey. The data was captured during the time period of the Artemis-1 mission, just under one month in duration.

NASA’s Orion spacecraft will carry astronauts further into space than ever before using a module based on Europe’s Automated Transfer Vehicles (ATV). Credit: NASA

Space radiation comes in two primary forms that pose risks to astronauts and spacecraft. Solar Particle Events occur during solar storms, releasing intense bursts of energetic particles from the Sun, while Galactic Cosmic Rays represent a constant stream of highly penetrating radiation from deep space. The findings enabled the team to assess current models for accuracy. They found that predictions match actual measurements to within 10-25% for the International Space Station, 4% for deep space conditions, and 10% for the Martian surface. This level of precision gives confidence in the existing models and in planning radiation protection for future missions.

They also found that, having assessed traditional shielding approaches, that they are largely ineffective against Galactic Cosmic Rays. In some cases, excessive shielding or inappropriate material choices can even amplify radiation exposure through secondary particle production. This occurs when the ‘original radiation’ creates a cascade of new particles on impact that can be more dangerous than the original radiation! They found that radiation levels vary substantially depending on location and the specific shielding configurations used! Quite the headache for engineers!

Radiation exposure is one of the greatest challenges in human space exploration. The study shows that our models for assessing radiation risk are reliable and that the ability to accurately assess those risks is crucial for protecting astronauts from serious health consequences. Having a good understanding of the risk directly influences how spacecraft are engineered, and plays a key role in mission planning for trips beyond Earth orbit. More work is needed now in the design of radiation protection systems if our space travellers are to be better protected from the long term risks posed by radiation.

Source : Validated space radiation exposure predictions from earth to mars during Artemis-I

The post We Know How Much Radiation Astronauts Will Receive, But We Don’t Know How to Prevent it appeared first on Universe Today.

Anthropogenic climate change is creating a vicious circle where rising temperatures are causing glaciers to melt at an increasing rate. In addition to contributing to rising sea levels, coastal flooding, and extreme weather, the loss of polar ice and glaciers is causing Earth’s oceans to absorb more solar radiation. The loss of glaciers is also depleting regional freshwater resources, leading to elevated levels of drought and the risk of famine. According to new findings by an international research effort, there has been an alarming increase in the rate of glacier loss over the last ten years.

The research was conducted by the Glacier Mass Balance Intercomparison Exercise (GlaMBIE) team, a major research initiative coordinated by the World Glacier Monitoring Service (WGMS). Located at the University of Zurich in collaboration with the University of Edinburgh and Earthwave Ltd, this international data repository and data analyzing service generates community estimates of glacier mass loss globally. The paper that details their research and findings, “Community estimate of global glacier mass changes from 2000 to 2023,” was published on February 19th in the journal Nature.

As part of their efforts, the team coordinated the compilation, standardization, and analysis of field measurements and data from optical, radar, laser, and gravimetry satellite missions. These include satellite observations from NASA’s Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2), the NASA-DLR Gravity Recovery and Climate Experiment (Grace), the GLR’s TanDEM-X mission, and the ESA’s CryoSat missions, and more.

Combining data from multiple sources, the Glambie team produced an annual time series of global glacier loss from 2000 to 2023. In 2000, glaciers covered about 705,221 square km (272,287 mi2) and held an estimated 121,728 billion metric tons (134,182 US tons) of ice. Over the next twenty years, they lost 273 billion tonnes of ice annually, approximately 5% of their total volume, with regional losses ranging from 2% in the Antarctic and Subantarctic to 39% in Central Europe. To put that in perspective, this amounts to what the entire global population consumes in 30 years.

In short, the amount of ice lost rose to 36% during the second half of the study (2012 and 2023) compared to the first half (2000-2011). Glacier mass loss over the whole study period was 18% higher than the meltwater from the Greenland Ice Sheet and more than double that from the Antarctic Ice Sheet. Michael Zemp, a noted glaciologist who co-led the study, said in an ESA press release:

“We compiled 233 estimates of regional glacier mass change from about 450 data contributors organized in 35 research teams. Benefiting from the different observation methods, Glambie not only provides new insights into regional trends and year-to-year variability, but we could also identify differences among observation methods. This means that we can provide a new observational baseline for future studies on the impact of glacier melt on regional water availability and global sea-level rise.”

This photograph, taken in 2012, shows the Golubin Glacier in Kyrgyzstan, in Central Asia. Credit: M. Hoelzle (2012)

Globally, glaciers collectively lost 6,542 tonnes (7,210 tons) of ice, leading to a global sea-level rise of 18 mm (0.7 inches). However, the rate of glacier ice loss increased significantly from 231 billion tonnes per year in the first half of the study period to 314 billion tonnes per year in the second half – an increase of 36%. This rise in water loss has made glaciers the second-largest contributor to global sea-level rise, surpassing the contributions of the Greenland Ice Sheet, Antarctic Ice Sheet, and changes in land water storage. Said UZH glaciologist Inés Dussaillant, who was involved in the Glambie analyses:

“Glaciers are vital freshwater resources, especially for local communities in Central Asia and the Central Andes, where glaciers dominate runoff during warm and dry seasons. But when it comes to sea-level rise, the Arctic and Antarctic regions, with their much larger glacier areas, are the key players. However, almost Thione-quarter of the glacier contribution to sea-level rise originates from Alaska.”

These results will provide environmental scientists with a refined baseline for interpreting observational differences arising from different methods and for calibrating models. They hope this will help future studies of global ice loss by narrowing the projection uncertainties for the twenty-first century. These research findings are the culmination of many years of cooperative studies and observations, which included the use of satellites that were not specifically designed to monitor glaciers globally. As co-author Noel Gourmelen, a lecturer in Earth Observation of the Cryosphere at the University of Edinburgh, said:

“The research is the result of sustained efforts by the community and by space agencies over many years, to exploit a variety of satellites that were not initially specifically designed for the task of monitoring glaciers globally. This legacy is already producing impact with satellite missions being designed to allow operational monitoring of future glacier evolution, such as Europe’s Copernicus CRISTAL mission which builds on the legacy of ESA’s CryoSat.”

The study also marks an important milestone since it was released in time for the United Nations’ International Year of Glaciers’ Preservation and the Decade of Action for Cryospheric Sciences (2025–2034). Said Livia Jakob, the Chief Scientific Officer & Co-Founder at Earthwave, hosted a large workshop with all the participants to discuss the findings. “Bringing together so many different research teams from across the globe in a joint effort to increase our understanding and certainty of glacier ice loss has been extremely valuable. This initiative has also fostered a stronger sense of collaboration within the community.”

The study also illustrates the importance of collective action on climate change, which is accelerating at an alarming rate. Research that quantifies glacial loss, rising sea levels, and other impacts is key to preparing for the worst. It’s also essential to the development of proper adaptation, mitigation, and restoration strategies consistent with the recommendations made by the UN Intergovernmental Panel on Climate Change (IPCC).

Further Reading: ESA

The post Glaciers Worldwide are Melting Faster Causing Sea Levels to Rise More appeared first on Universe Today.

Satellites often face a disappointing end: despite having fully working systems, they are often de-orbited after their propellant runs out. However, a breakthrough is on the cards with the launch of China’s Shijian-25 satellite which has been launched into orbit to test orbital refuelling operations. The plan; docking with satellite Beidou-3 G7 and transferring 142 kilograms of hydrazine to extend its life by 8 years! It’s success will mean China plans to develop a network of orbital refuelling stations!

Like cars on Earth, satellites need fuel to manoeuvre and for their constantly decaying orbits to be boosted. But unlike vehicles on the ground, when satellites run out of propellant, they become expensive space debris. This challenge has driven the development of orbital refuelling technology, which could extend satellite lifespans and transform space operations.

An artist’s conception of ERS-2 in orbit. ESA

The International Space Station (ISS) offers one of the most well known examples of an orbiting ‘satellite’ and it too needs to deal with boosting its orbit. The problem is the drag imposed upon the structures by gas in our atmosphere. In the case of the ISS, docked supply craft are typically used to fire their engines to reposition ISS to the correct altitude. Without these periodic “orbital boosts,” the ISS would eventually lose altitude and reenter the atmosphere.

The International Space Station (ISS) in orbit. Credit: NASA

A significant milestone in autonomous refuelling came in 2007 with DARPA’s Orbital Express mission. This demonstration involved two spacecraft: the ASTRO servicing vehicle and a prototype modular satellite called NextSat. Over three months, they performed multiple autonomous fuel transfers and component replacements, proving that robotic spacecraft could conduct complex servicing operations without direct human control.

The technology continues to advance with China’s Shijian-25 satellite (launched on 6 January 2025) representing another step forward in orbital refuelling capabilities. The mission aims to demonstrate refuelling operations in geosynchronous orbit approximately 36,000 kilometres above Earth. This is particularly significant because geosynchronous orbits often host communications satellites that benefit from life extension.

The technical challenges of orbital refuelling are considerable though. Spacecraft must achieve extremely precise rendezvous and docking while travelling in excess of 28,000 kilometres per hour. The fuel transfer system must prevent leaks, which could be hazardous to both spacecraft and create hazardous debris. Adding to the challenge is that many satellites were never designed with refuelling in mind, lacking any form of standardised fuel ports or docking interfaces.

Orange balls of light fly across the sky as debris from a SpaceX rocket launched in Texas is spotted over Turks and Caicos Islands on Jan. 16, in this screen grab obtained from social media video. Credit: Marcus Haworth/Reuters

Looking ahead, several companies and space agencies are developing orbital refuelling systems. These range from dedicated “gas station” satellites to more versatile servicing vehicles that can perform repairs and upgrades alongside refuelling. As the technology advances, it could significantly change how we operate in space, making satellite operations more sustainable and cost-effective.

Source : China successfully sent Shijian-25 satellite

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Astronomers have known for some time that nearby supernovae have had a profound effect on Earth’s evolution. For starters, Earth’s deposits of gold, platinum, and other heavy metals are believed to have been distributed to Earth by ancient supernovae. The blasts of gamma rays released in the process can also significantly affect life, depleting nitrogen and oxygen in the upper atmosphere, depleting the ozone layer, and causing harmful levels of ultraviolet radiation to reach the surface. Given the number of near-Earth supernovae that have occurred since Earth formed 4.5 billion years ago, these events likely affected the evolution of life.

In a new paper by a team of astronomers from the University of California Santa Cruz (UCSC), a nearby supernova may have influenced the evolution of life on Earth. According to their findings, Earth was pummeled by radiation from a nearby supernova about 2.5 million years ago. This burst of radiation was powerful enough to break apart the DNA of living creatures in Lake Tanganyika, the deepest body of water in Africa. This event, they argue, could be linked to an explosion in the number of viruses that occurred in the region.

The study was led by Caitlyn Nojiri, a recent graduate of the USCS Department of Astronomy and Astrophysics. She was joined by Enrico Ramirez-Ruiz, a USCS Professor of astronomy and astrophysics, and Noémie Globus, a postdoctoral fellow at USCS and a member of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University and the Astrophysical Big Bang Laboratory. The paper that describes their findings appeared on January 15th in the journal Astrophysical Journal Letters.

The image of Lake Tanganyika was acquired in June 1985. Credit: NASA

For their study, the team examined samples of iron-60 retrieved from the seafloor of Lake Tanganyika, the 645 km-long (400 mi) lake in Africa’s Great Rift Valley that borders Burundi, Tanzania, Zambia, and the Democratic Republic of Congo. This radioactive isotope of iron is produced by supernovae and is extremely rare on Earth. They obtained age estimates based on how much the samples had already broken down into nonradioactive forms. This revealed two separate ages for the samples, some 2.5 million years old and the others 6.5 million years old.

The next step was to trace the origin of the iron isotopes, which they did by backtracking the Sun’s motions around the center of the Milky Way. Roughly 6.5 million years ago, our Solar System passed through the Local Bubble, a region of lower density in the interstellar medium (ISM) of the Orion Arm in the Milky Way. As the Solar System entered the Bubble’s stardust-rich exterior, Earth was seeded with the older traces of iron-60. Between 2 and 3 million years ago, a neighboring star went supernova, seeding Earth with the younger traces of iron-60.

To confirm this theory, Nojiri and her colleagues conducted a simulation of a near-Earth supernova, which indicated that it would have bombarded Earth with cosmic rays for 100,000 years after the blast. This model was consistent with a previously recorded spike in radiation that hit Earth around that time. Given the intensity of the radiation, this raised the possibility that it was enough to snap strands of DNA in half. In the meantime, the authors came upon a study of virus diversity in one of Africa’s Rift Valley lakes and saw a possible connection. Said Nojiri in a UCSC news release:

“It’s really cool to find ways in which these super distant things could impact our lives or the planet’s habitability. The iron-60 is a way to trace back when the supernovae were occurring. From two to three million years ago, we think that a supernova happened nearby. We saw from other papers that radiation can damage DNA. That could be an accelerant for evolutionary changes or mutations in cells. We can’t say that they are connected, but they have a similar timeframe. We thought it was interesting that there was an increased diversification in the viruses.”

Lead author Caitlyn Nojiri is now applying for graduate school and hopes to get a Ph.D. in astrophysics. Credit: UCSC

Shortly after their paper was published, Nojiri became the first UCSC undergraduate to be invited to give a seminar at the Center for Cosmology and AstroParticle Physics (CCAPP) at Ohio State. Nojiri did not initially set out to be an astronomer but eventually arrived at UCSC, where Prof. Ramirez-Ruiz encouraged her to apply for the University of California Leadership Excellence through Advanced Degrees (UC LEADS) program. This program is designed to identify undergraduate students from diverse backgrounds who have the potential to succeed in STEM.

She also participated in the Lamat program (“star” in Mayan), which was founded by Ramirez-Ruiz to teach students with great aptitude and nontraditional backgrounds how to conduct research in astronomy. Because of her experience with these programs, Nojiri has decided to apply for graduate school and become an astrophysicist.

“People from different walks of life bring different perspectives to science and can solve problems in very different ways,” said Ramirez-Ruiz. “This is an example of the beauty of having different perspectives in physics and the importance of having those voices.”

Further Reading: UC Santa Cruz, The Astrophysical Journal

The post New Study Proposes that Cosmic Radiation Altered Virus Evolution in Africa appeared first on Universe Today.

How can we explore Saturn’s moon, Enceladus, to include its surface and subsurface ocean, with the goal of potentially discovering life as we know it? This is what a recent study presented at the American Geophysical Union (AGU) 2024 Fall Meeting hopes to address as a team of students and researchers proposed the Thermal Investigation of Geothermal Regions of Enceladus (TIGRE) mission concept, which is designed to conduct in-depth exploration of Enceladus with an orbiter, lander, and drill, while laying the groundwork for future missions to icy moons throughout the solar system.

Here, Universe Today discusses this incredible mission concept with Prabhleen Kour, who is a senior at River Valley High School in Yuba City, CA, and lead author of the study, regarding the motivation behind TIGRE, how TIGRE can improve upon findings from NASA’s now-retired Cassini mission, potential landing sites on Enceladus, how TIGRE can improve missions to other icy moons, the next steps in making TIGRE a reality, and whether she thinks Enceladus has life. Therefore, what was the motivation behind TIGRE?

“TIGRE mission was born during our time with the NASA STEM Enhancement in Earth Science (SEES) program in collaboration with UT Austin’s Center for Space Research,” Kour tells Universe Today. “As part of our internship, our team was tasked to design a space mission within our solar system based on a few assigned parameters. The designed mission had to be aligned to current work being performed by NASA but separate from active missions such as the Europa Clipper. Similarly, the main subject of our mission, Enceladus, and our goals with it, had to be chosen in accordance with the Decadal Survey which dictates what missions and priorities space agencies have. In our case, we were driven to explore a celestial body that might hold the signs of life.”

The TIGRE mission concept comes more than seven years after NASA’s Cassini-Huygen mission ended by performing an intentional dive into Saturn, resulting in Cassini breaking apart in Saturn’s atmosphere. During its storied mission, Cassini spent more than 13 years conducting the most in-depth exploration of Saturn and its many moons, including Titan, Mimas, Atlas, Daphnis, Pandora, Iapetus, Rhea, Dione, Pan, Hyperion, and Enceladus.

Of these moons, Titan and Enceladus are the only two that exhibit potential conditions for life, as Titan is the only moon in the solar system with a dense atmosphere and contains lakes of liquid methane and ethane, while Enceladus boasts a large subsurface ocean that discharge geysers of liquid water from its large crevices in its south pole, dubbed Tiger Stripes. It is the geysers of Enceladus that Cassini not only discovered but flew through twice during its mission, identifying water, carbon dioxide, and a myriad of hydrocarbons and organic materials, the last of which exhibited density 20 times greater than predicted. Therefore, how does TIGRE improve upon findings from the Cassini mission?

Image of Enceladus’ south pole geysers obtained by NASA’s Cassini spacecraft in June 2009. (Credit: NASA/JPL/Space Science Institute)

“Though Cassini’s flyby was incredible and provided us with great information, TIGRE aims to get an incredibly close look at Enceladus’ secrets,” Kour tells Universe Today. “Since TIGRE is designed to go on the surface of Enceladus, it will get more of the ‘inside scoop’ than Cassini. Cassini has already helped us by identifying the organic molecules contained within the ocean, now we want to explore other factors that might make life possible on Enceladus. We are planning to locate any potential regions of interest and stability of habitable zones, analyze samples for organic/inorganic indicators of prebiotic lifeforms, and utilize our findings for future missions. The TIGRE mission contains a drill design, which will reach the subsurface ocean and collect water samples for elements such as CHONPS.”

Enceladus’ Tiger Stripes consist of four main features officially named Damascus Sulcus, Baghdad Sulcus, Cairo Sulcus, and Alexandria Sulcus, with a smaller feature branching off Alexandria called Camphor Sulcus (sulcus being plural for sulci and is an astrogeology term meaning parallel ridges), and are responsible for the geysers that discharge Enceladus’ interior ocean into space. The thickness of the ice in this region is estimated to be approximately 5 kilometers (3.1 miles). Since one of the primary goals of the TIGRE mission is to obtain drill samples of the ocean and identify potential signs of life, the team targeted the Tiger Stripes as potential landing sites for a craft to land and obtain samples of the ocean.

To accomplish this, the team outlined specific landing site criteria to maximize mission success, including landing on relatively flat terrain near a geyser, but not directly on a geyser, to avoid being damaged by uneven terrain or disrupted during geyser activity. Additionally, they determined a low-elevation region would be substantial to minimize the amount of ice the drill would have to penetrate to obtain samples. In the end, the team chose a primary landing site located near the Baghdad stripe that met their landing criteria, located approximately 6.4 kilometers (4 miles) from a geyser and a surface elevation of approximately 450 meters (1,476 feet), along with potential backup landing sites.

Enceladus’ Tiger Stripes. (Credit: NASA/JPL/Space Science Institute)

“Our decision to land near the Baghdad stripe was due to the following: Flat terrain to prevent lander damage, proximity to a geyser, and low elevation to minimize drilling distance,” Kour tells Universe Today. “Any other location that met these requirements were deemed as backups. We analyzed multiple different locations throughout the four stripes, and there were a few that met the requirements on the Cairo stripe. More specifically, one location of interest was between a large geyser and a smaller geyser on the Cario stripe. However, because the location on the Baghdad stripe was close to multiple other smaller geysers, we chose the Baghdad location.”

As noted, Enceladus isn’t the only moon of Saturn that is deemed to potentially have life, as its largest moon, Titan, has a dense and hazy atmosphere caused by specific chemical reactions that scientists have hypothesized existed on early Earth. Additionally, its lakes of liquid methane and ethane have also become prime targets for astrobiologists. Outside of the Saturn system, other icy moons exist throughout the solar system that potentially once had life or could have life today, including Jupiter’s moons, Europa and Ganymede, with both presenting evidence of subsurface oceans circulating beneath their icy crusts.

Venturing closer to the Sun and inside the main asteroid belt orbits the dwarf planet Ceres, which NASA’s Dawn spacecraft identified frozen salts caused by a process known as cryovolcanism. Current models debate the interior structure of Ceres, but it is hypothesized that it once had liquid water long ago. Finally, venturing to the outer portions of the solar system orbits Neptune’s moon, Triton, which NASA’s Voyager 2 spacecraft identified active geysers on its surface comprised of cryolava lakes. Since one of the primary mission objectives of TIGRE is to improve future missions to icy moons, how will it accomplish this?

“The mission will help advance remote sensing, orbiting, landing, and thermal drilling technologies, setting a precedent for future exploration,” Kour tells Universe Today. “TIGRE consists of three main components: the orbiter, lander, and drill. This design is not limited to Enceladus’ surface alone. Instead, this design can be applicable to many other icy surfaces, including those on Earth like Antarctica and other icy moons. Data from the lander’s sampling devices, thermal drill, and the orbiter’s remote sensing will provide comprehensive insights into the composition and formation of Enceladus’s subsurface ocean. These findings could also inform our understanding of other icy moons, broadening our knowledge of potentially habitable environments in the outer Solar System.”

As Universe Today recently discussed with the VATMOS-SR mission concept, it can take anywhere from years to decades for a space mission to go from a concept to reality, involving a myriad of steps and phases, including design, funding rounds, testing, re-designs, re-testing, until it’s finally built and launched. This is followed by several years of traveling to the destination, arriving, and finally collecting science.

For example, the Cassini-Huygens mission was first proposed in 1982 and wasn’t launched until 1997, during which time it endured several years of studies and swapped between a solo NASA mission or a joint NASA-European Space Agency mission, the latter of which was settled upon. After launching in 1997, Cassini finally arrived at Saturn in July 2004, landing the Huygens probe on Titan in January 2005, and spent until 2017 obtaining treasure troves of images and data about Saturn and its many moons, even discovering a few moons along the way and diving through Enceladus’ plumes. Given the journey that Cassini endured, what are the next steps in making TIGRE a reality?

“One of the first steps in making TIGRE a reality is waiting for the completion of the Europa Clipper mission,” Kour tells Universe Today. “In waiting for the mission’s completion, we will be able to see what worked and failed to gather useful samples and what failed to navigate space’s harsh environment. In the meantime, we can advocate for the significance of finding life to enlarge NASA’s budget for active missions. This itself would be a step towards launching the TIGRE mission by opening the resources for improving and testing our mission’s main components (the orbiter, lander, and drill) against the extreme cold, ocean waters, and radiation.”

As noted, Enceladus is a prime target for astrobiologists in the search for life beyond Earth due to its vast subsurface ocean circulating beneath its icy shell. As demonstrated here on Earth, liquid water leads to life as we know it, so Enceladus having a liquid water ocean, even a subsurface ocean, is a strong indicator that it could potentially also have life as we know it, too.

The hydrocarbons discovered by Cassini when the spacecraft flew through Enceladus’ plumes included carbon-bearing molecules like formaldehyde, acetylene, propane, and methane, which is evidence for hydrothermal activity occurring on the ocean floor of Enceladus, much like hydrothermal activity exists on the ocean floors of Earth, specifically regarding the water-rock interactions that occur here, as well. Therefore, in Kour’s opinion, does Enceladus have life and what kinds of life does she foresee finding within their potential TIGRE samples?

“It is not a stretch of reason to state Enceladus could harbor life,” Kour tells Universe Today. “As previously mentioned, Enceladus has the components for life through key elements and has the energy activity to make the possibility of life more plausible. Within the depths of its oceans, Enceladus may very well have life. However, we do not want to explicitly state that there is something there, as there are so many factors at play – thin atmosphere, other chemicals that were potentially not detected by Cassini, and environmental conditions. If there is life and it is similar to the one on Earth, we could expect it to be one of close relations to Archaea. The representatives of this domain are quite primitive and unicellular, which aligns with our hypothesis of Enceladus being able to harbor a simple life form. However, it can also survive harsh conditions – such as extreme cold temperatures on the moon and radiation.”

How will TIGRE help scientists better understand Enceladus and potentially other icy moons throughout the solar system in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Sampling Enceladus’ Subsurface Ocean with TIGRE Mission Concept appeared first on Universe Today.

Have you ever wondered how astronomers manage to map out the Milky Way when it’s so incredibly vast? One of the most powerful tools is something called 21cm radiation.

Hydrogen, the most abundant element in the universe, plays a key role here. When the electrons in hydrogen atoms flip their spin direction, a specific type of electromagnetic radiation is emitted at a wavelength of 21 centimeters.

The Milky Way galaxy is packed with hydrogen atoms, and these atoms are constantly emitting 21cm radiation. The best part is that this radiation can travel long distances through the interstellar dust that often obscures our view of the galaxy in visible light. This makes 21cm radiation an incredibly useful tool for mapping the structure of the Milky Way.

This radiation reveals everything from star-forming gas clouds to the shapes of the galaxy’s spiral arms. Whereas visible light just gets caught up in all the interstellar dust at it tries to traverse the tens of thousands of light-years across the galaxy, 21cm radiation just sails right though.

But mapping the galaxy’s structure is just one part of the story. Astronomers can also learn about the Milky Way’s rotation by studying the redshift and blueshift of the 21cm radiation. When an object in space moves away from us, the wavelength of the light or radiation it emits gets stretched out, making it appear redder (redshift). Conversely, when an object moves toward us, the wavelength gets compressed, making it appear bluer (blueshift).

By analyzing the redshift and blueshift of the 21cm radiation from different parts of the galaxy, astronomers can determine how fast various regions of the Milky Way are rotating. This information helps them build a more comprehensive picture of our galaxy’s dynamics and motion.

The utility of 21cm radiation isn’t limited to the Milky Way alone. Astronomers can use these same techniques to study distant galaxies as well. By examining the neutral hydrogen gas clouds in far-off galaxies, they can estimate the masses of these galaxies. This is because the amount of 21cm radiation emitted is related to the number of hydrogen atoms present, which in turn gives clues about the galaxy’s overall mass.

21cm radiation is a powerful tool in the field of astronomy that allows astronomers to map the structure of our Milky Way galaxy, understand its rotation, and even estimate the masses of distant galaxies. This technique opens a window into the vast and complex universe, helping us unravel the mysteries of the cosmos with every new observation.

So next time you gaze up at the night sky, remember that there’s a whole lot more going on than meets the eye. Thanks to 21cm radiation, we’re able to peel back the layers of the Milky Way and explore the wonders of the universe in ways that were once unimaginable.

The post How Astronomers Make Deep Maps of the Milky Way appeared first on Universe Today.

NASA astronomers have been continuing to monitor the trajectory of asteroid 2024 YR4. The initial calculations suggested a 1.3% probability of an Earth impact event, which temporarily increased to 3.1% as more data came in. However, and with a sigh of relief, recent analysis brings encouraging news: the Earth impact probability has decreased significantly to 0.28%, though calculations now show a 1% chance of lunar impact. Observations will continue with the James Webb Space Telescope so stay tuned. 

Asteroids are rocky, airless worlds that are remnants left over from the formation of our Solar System about 4.6 billion years ago. They range in size from tiny pebbles to massive bodies hundreds of kilometres across. Most asteroids are found in the asteroid belt between the orbits of Mars and Jupiter although some follow paths that bring them closer to Earth.  Occasionally, they can pose a threat to Earth, which is why astronomers and space agencies closely monitor their orbits and develop potential deflection techniques.

Asteroid Ryugu as seen by Japan’s Hayabusa 2 spacecraft, which returned a sample of the ancient asteroid to Earth in 2020. Image Courtesy ISAS/JAXA

Asteroid 2024 YR4 is one such asteroid that has had gripped the nations media over recent weeks. It’s a near-Earth object that was discovered on 27 December 2024, by the Asteroid Terrestrial-impact Last Alert System (ATLAS) in Chile. Initially, it had an estimated 1.3% chance of impact with Earth in 2032, making it one of the highest-risk asteroids ever recorded. However, further observations raised that risk!

Atlas 2 on Mauna Loa

Astronomers use systems like ATLAS to identify near-Earth objects (NEOs) that could pose a potential threat to our planet. It was developed by the University of Hawaii and funded by NASA and consists of a network of telescopes positioned around the world to provide continuous sky surveys. Its primary goal is to detect asteroids before a potential impact, allowing for timely warnings and mitigation efforts. Since its installation, ATLAS has successfully discovered thousands of asteroids, including hazardous ones just like 2024 YR4. 

Understanding the level of threat from asteroids like 2024 YR4 requires time, time and observations. Imagine a game of tennis and the ball is hit, sending it flying over the net. A photographer sat in the crowd grabs a snapshot of the ball as it flies over the net. The picture is a clear, sharp capture of a point in time however analysis of the image can only reveal the exact location of the ball and not its trajectory. It’s the same with asteroids, once they are discovered, a single observation will reveal where it is but a series of observations are required to understand where it’s going. Ok so this is a simplistic view but it shows how important continued observations are to asteroids like 2024 YR4.

Further observations of asteroid 2024 YR4, conducted during the night of 19-20 February have revealed encouraging results. NASA’s planetary defence team have reported that the probability of an Earth impact has decreased to 0.28%. Monitoring will of course continue to refine trajectory predictions, but current calculations indicate a slight increase in the possibility of lunar impact, now estimated at 1%. These percentages are of course tiny and pose no cause for alarm but 2024 YR4 will continue to be observed over the coming months, just to be sure.

Source : Additional Observations Continue to Reduce Chance of Asteroid Impact in 2032

The post NASA Downgrades the Risk of 2024 YR4 to Below 1% appeared first on Universe Today.

Some exoplanets have characteristics totally alien to our Solar System. Hot Jupiters are one such type. They can have orbital periods of less than 10 days and surface temperatures that can climb to well over 4,000 K (3,730 °C or 6,740 °F). Unlike any planets in our system, they’re usually tidally locked.

Astronomers probed the atmosphere of one hot Jupiter and found some strange winds blowing.

The planet is WASP-121 b, also known as Tylos. It is about 860 light-years away from Earth in the constellation Puppis. It has about 1.16 Jupiter masses and a radius about 1.75 times that of Jupiter. It’s extremely close to its main sequence star and completes an orbit every 1.27 days. Tylos is tidally locked to its star, and its dayside temperature is 3,000 Kelvin (2,730 °C or 4,940 °F), qualifying it as an ultra-hot Jupiter.

“It feels like something out of science fiction.”

Julia Seidel, European Southern Observatory

Since its discovery in 2015, Tylos’ atmosphere has been studied many times. Researchers found water in its stratosphere and hints of titanium oxide and vanadium oxide. They’ve also detected iron and chromium, though some subsequent studies failed to replicate some of these findings.

In new research, scientists examined Tylos’ atmosphere in greater detail with the four telescopes that make up the VLT. With help from the VLT’s ESPRESSO instrument, the researchers found powerful winds blowing through the exoplanet’s atmosphere and confirmed the presence of iron and titanium. The results are in two new papers.

“Even the strongest hurricanes in the Solar System seem calm in comparison.”

Julia Seidel, European Southern Observatory

The first paper, “Vertical structure of an exoplanet’s atmospheric jet stream,” was published in Nature. The lead author is Julia Seidel, a researcher at the European Southern Observatory (ESO).

The second is “Titanium chemistry of WASP-121 b with ESPRESSO in 4-UT mode,” which was published in the journal Astronomy and Astrophysics. The lead author is Bibiana Prinoth, a PhD student at Lund University, Sweden, who is also with the European Southern Observatory.

Some of the researchers involved are co-authors of both papers.

“Ultra-hot Jupiters, an extreme class of planets not found in our solar system, provide a unique window into atmospheric processes,” the authors of the Nature paper write. “The extreme temperature contrasts between their day- and night-sides pose a fundamental climate puzzle: how is energy distributed?”

An artist’s impression of Tylos, also known as WASP-121 b. Image Courtesy: NASA, ESA, Q. Changeat et al., M. Zamani (ESA/Hubble)

“This planet’s atmosphere behaves in ways that challenge our understanding of how weather works — not just on Earth, but on all planets. It feels like something out of science fiction,” said Julia Seidel, the lead author of the study published in Nature.

With the power of the VLT and ESPRESSO, the researchers were able to study Tylos’ atmosphere in detail. No other exoplanet atmosphere has ever been studied in such detail and to such depth. The researchers created a 3D map of the atmosphere, revealing distinct layers and winds.

Tylos’ atmosphere is divided into three layers, with iron winds at the bottom, followed by a very fast jet stream of sodium, and finally, an upper layer of hydrogen winds. This kind of climate has never been seen before on any planet. Image Credit: ESO/M. Kornmesser

“What we found was surprising: a jet stream rotates material around the planet’s equator, while a separate flow at lower levels of the atmosphere moves gas from the hot side to the cooler side. This kind of climate has never been seen before on any planet,” said Seidel. The observed jet stream spans half of the planet, gaining speed and violently churning the atmosphere high up in the sky as it crosses the hot side of Tylos. “Even the strongest hurricanes in the Solar System seem calm in comparison,” she adds.

“It’s truly mind-blowing that we’re able to study details like the chemical makeup and weather patterns of a planet at such a vast distance.”

Bibiana Prinoth, Lund University and the European Southern Observatory

The VLT has an interesting design and is billed by the European Southern Observatory as “the world’s most advanced visible-light astronomical observatory.” It has four main units with 8.2-meter primary mirrors and four smaller, movable auxiliary ‘scopes with 1.8-meter primary mirrors. When working together with the ESPRESSO instrument, the VLT operates as a single, powerful telescope. This combined power meant that the VLT gathered ample data during a single transit of Tylos in front of its star.

“The VLT enabled us to probe three different layers of the exoplanet’s atmosphere in one fell swoop,” said study co-author Leonardo A. dos Santos, an assistant astronomer at the Space Telescope Science Institute. The researchers traced the movement of the winds by tracking the movements of different elements: iron, sodium, and hydrogen correspond to the deep, mid, and shallow layers of the atmosphere. “It’s the kind of observation that is very challenging to do with space telescopes, highlighting the importance of ground-based observations of exoplanets,” he adds.

This diagram shows the structure and motion of the atmosphere of the exoplanet Tylos (WASP-121b). The exoplanet is shown from above in this figure, looking at one of its poles. The planet rotates counter-clockwise in such a way that it always shows the same side to its parent star. One side is perpetual day, and the other is perpetual night. The transition between night and day is the “morning side,” while the “evening side” represents the transition between day and night; its morning side is to the right, and its evening side is to the left. Image Credit: ESO/M. Kornmesser

The observations revealed an exoplanet atmosphere with unusual complexity.

When Tylos crosses in front of its host star, known as a transit, atoms in the planet’s atmosphere absorb specific wavelengths of starlight, which was measured with the VLT’s ESPRESSO instrument. With that data, astronomers reconstructed the composition and velocity of different layers in the atmosphere. An iron wind blows in the deepest layer, away from the point of the planet where the star is directly overhead. Above the iron layer is a very fast jet of sodium that moves faster than the planet rotates. The sodium jet accelerates as it moves from the planet’s morning side to its evening side. The upper layer is made of hydrogen, where the wind blows outwards. The hydrogen layer overlaps with the sodium jet below it.

The authors explain that this unusual planet is more than just an oddity. Its unusual characteristics make it a great testbed for Global Circulation Models. “By resolving the vertical structure of atmospheric dynamics, we move beyond integrated global snapshots of the atmosphere, enabling more accurate identification of flow patterns and allowing for a more nuanced comparison to models,” the authors explain.

The study published in Astronomy and Astrophysics is also based on data from the VLT and ESPRESSO. It uncovered more details of Tylos’ atmosphere, including its chemistry. “The transmission spectrum of WASP-121 b has been extensively studied using the cross-correlation technique, resulting in detections and confirmations for various atoms and ions, including H I, Mg I, Ca I, V I, Cr I, Fe I, Ni I, Fe II, Ca II, and K I, Ba II,” the authors write. “We confirm all these detections and additionally report detections for Ti I, Mn I, Co I Sr I, and Sr II.”

“This experience makes me feel like we’re on the verge of uncovering incredible things we can only dream about now.”

Bibiana Prinoth, Lund University and the European Southern Observatory

The researchers found titanium just below the jet stream. This finding is interesting because previous research detected titanium and subsequent research refuted that. “We attribute the capability of detecting Ti I to the superior photon-collecting power enabled by using ESPRESSO in 4-UT mode compared to a single 1-UT transit and to improvements in the application of the cross-correlation technique,” the authors explain.

The cross-correlation technique is a powerful method for studying exoplanet atmospheres. Light from the atmosphere is much fainter than light from the star and can be obscured by the much stronger starlight. The cross-correlation technique helps overcome this by comparing the observed spectrum with the known “template” spectrum of specific molecules and atoms expected to be present in the atmosphere.

This figure shows the two-dimensional cross-correlation function of H I, Li I, Na I, Mg I, K I, Ca I, Ti I, V I, Cr I, Mn I, Fe I, Fe II, Co I, Ni I, Ba II, Sr I and Sr II. The last panel shows the cross-correlation function for the entire atmospheric model. Image Credit: Prinoth et al. 2025.

“It’s truly mind-blowing that we’re able to study details like the chemical makeup and weather patterns of a planet at such a vast distance,” said Bibiana Prinoth, lead author of the Astronomy and Astrophysics paper.

“The 4-UT mode of ESPRESSO, with its effective photon collecting area equivalent to that of a 16-meter class telescope, serves as a valuable test-bed for pushing the limits of S/N on relatively faint targets,” the authors write in their conclusion.

The study of exoplanet atmosphere with ground-based telescopes will soon get a big boost. In 2028, the long-awaited Extremely Large Telescope should begin operations. It will have a 39.3-metre-diameter primary mirror, giving it 250 times more light-gathering area than the Hubble. It will also feature powerful instruments to probe exoplanet atmospheres.

“The present analysis also allows us to anticipate the observational capabilities of the soon-to-be-commissioned ELT, particularly with regard to time-resolved studies of exoplanet atmospheres,” the authors write.

Who knows what further strangeness is waiting to be discovered in exoplanet atmospheres?

“The ELT will be a game-changer for studying exoplanet atmospheres,” said Prinoth. “This experience makes me feel like we’re on the verge of uncovering incredible things we can only dream about now.”

• Press Release: First 3D observations of an exoplanet’s atmosphere
• Research: Vertical structure of an exoplanet’s atmospheric jet stream
• Research: Titanium chemistry of WASP-121 b with ESPRESSO in 4-UT mode

The post Strange Winds Blow Through this Exoplanet’s Atmosphere appeared first on Universe Today.

Stars form in Giant Molecular Clouds (GMCs), vast clouds of mostly hydrogen that can span tens of light years. These stellar nurseries can form thousands of stars. Astronomers know this because they observe these regions in the Milky Way and the Magellanic Clouds and watch as stars take shape.

But the Universe is more than 13 billion years old and has been forming stars for almost that entire time. The early Universe was different in notable ways. Was star formation any different in the early Universe?

One of the main differences between the early Universe and the modern Universe is metallicity. Elements heavier than hydrogen and helium, called metals in astronomy, didn’t exist in the very early Universe. Only after massive stars formed and died did the Universe’s metallicity increase. Metallicity affects many different processes, including star formation. Metals help cool down clouds of gas and dust, allowing them to collapse and form stars.

Scientists know a lot about the star formation process, but there are many outstanding questions. One of them concerns star formation in the early, low-metallicity Universe. How different was the star formation process billions of years ago?

“We can’t go back in time to study star formation in the early universe, but we can observe parts of the universe with environments similar to the early universe.”

Kazuki Tokuda, Kyushu University, Japan

New research in The Astrophysical Journal tackled the question. It’s titled “ALMA 0.1 pc View of Molecular Clouds Associated with High-mass Protostellar Systems in the Small Magellanic Cloud: Are Low-metallicity Clouds Filamentary or Not?” The lead author is Kazuki Tokuda, a Post-doctoral fellow in the Department of Earth and Planetary Sciences in the Faculty of Science at Kyushu University in Japan. Tokuda is also affiliated with the National Astronomical Observatory of Japan.

This simulation shows stars forming in a molecular cloud, including the jets emitted by young protostars. Astrophysicists know a lot about the star-formation process, but there are still many questions awaiting comprehensive answers. Video Credit: Mike Grudic/STARFORGE

“Even today our understanding of star formation is still developing, comprehending how stars formed in the earlier universe is even more challenging,” said lead author Tokuda in a press release. “The early universe was quite different from today, mostly populated by hydrogen and helium. Heavier elements formed later in high-mass stars. We can’t go back in time to study star formation in the early universe, but we can observe parts of the universe with environments similar to the early universe.”

One of those places is the Small Magellanic Cloud (SMC), a dwarf galaxy near the Milky Way. The SMC’s metallicity is much lower than the Milky Way’s, containing only about one-fifth as many metals. This makes it analogous to the early Universe about 10 billion years ago.

In the Milky Way, star-forming molecular clouds tend to have a filamentary structure. Astronomers have wondered whether these same filamentary shapes are a universal feature found throughout cosmic time. “To test whether these structures are universal throughout cosmic star formation history, it is crucial to study low-metallicity environments within the Local Group,” the authors explain in their paper. Since the SMC is a close neighbour and also has a low metallicity, it’s a good place to look. However, searching the SMC for these filamentary features has been difficult due to the insufficient spatial resolution of many observatories.

The researchers used the Atacama Large Millimeter-submillimeter Array’s (ALMA) power to examine the SMC and see if it has the same star-forming filamentary structures. They focused on the molecular clouds associated with massive young stellar objects (YSOs) in the (SMC).

This image from the research shows the overall view of the SMC and the positions of the target YSOs. Image Credit: Tokuda et al. 2025.

“In total, we collected and analyzed data from 17 molecular clouds. Each of these molecular clouds had growing baby stars 20 times the mass of our Sun,” said lead author Tokuda in a press release. “We found that about 60% of the molecular clouds we observed had a filamentary structure with a width of about 0.3 light-years, but the remaining 40% had a ‘fluffy’ shape. Furthermore, the temperature inside the filamentary molecular clouds was higher than that of the fluffy molecular clouds.”

This figure from the new research shows the 17 molecular clouds the researchers observed with ALMA. Most had the same filamentary shape as clouds in the Milky Way, shown in the yellow boxes. But 40% had a fluffy shape, as shown in the blue boxes. Image Credit: (ALMA (ESO/NAOJ/NRAO), Tokuda et al. 2025, ESA/Herschel)

In their paper, the authors describe it this way: “Our analysis shows that about 60% of the clouds have steep radial profiles from the spine of the elongated structures, while the remaining clouds have a smooth distribution and are characterized by lower brightness temperatures. We categorize the former as filaments and the latter as nonfilaments.”

This figure shows the 17 molecular clouds in the study. The ones with yellow check marks are the ones identified as filaments. Image Credit: Tokuda et al. 2025.

The clouds were not uniform and displayed a diversity of shapes. The researchers classified them into four separate types: single filaments, hub filaments, spatially compact clouds, and diffuse clouds.

These panels illustrate the four types of filaments the authors used to categorize their observations: (a) single filaments, (b) hub filaments, (c) spatially compact clouds, and (d) diffuse clouds. Image Credit: Tokuda et al. 2025.

The temperature difference between the filamentary and fluffy shapes was probably due to their ages. The authors think all clouds started out as filamentary and had high temperatures due to cloud-to-cloud collisions. The clouds have weak turbulence when the temperatures are higher.

However, as the temperature drops, the movement of the incoming gas creates more turbulence. This smooths out the filamentary structure, creating the fluffy shapes.

According to the research, filamentary and fluffy clouds form stars differently. Clouds that hold onto their filamentary shapes are more likely to break apart along their length and form many lower-mass stars similar to our Sun, including planetary systems. When the filamentary structure changes to a fluffy structure, it becomes more difficult for such stars to form.

The implication is that the morphology of the clouds tells us about their evolutionary stages.

“Some of the filamentary clouds are associated with YSOs with outflows and exhibit higher temperatures, likely reflecting their formation conditions, suggesting that these clouds are younger than the nonfilamentary ones,” the authors write in their paper.

The study also emphasizes that the same temperature and structure changes have not been observed in higher metallicity environments like the Milky Way. “Such transitions in structure and temperature have not been reported in metal-rich regions, highlighting a key behaviour for characterizing the evolution of the interstellar medium and star formation in low-metallicity environments,” the authors explain.

With these results, Tokuda says the next step will be to compare them with observations of the Milky Way and other environments richer in heavy elements.

“This study indicates that the environment, such as an adequate supply of heavy elements, is crucial for maintaining a filamentary structure and may play an important role in the formation of planetary systems,” said Tokuda. “In the future, it will be important to compare our results with observations of molecular clouds in heavy-element-rich environments, including the Milky Way galaxy. Such studies should provide new insights into the formation and temporal evolution of molecular clouds and the universe.”

There are still more details to uncover about these filaments, what shapes them, and how they affect the stars they form. How does turbulence play its role? What role do magnetic fields play? Some filaments host YSOs with protostellar outflows. How does that radiative feedback affect the filaments?

Future research will address those questions.

“Future studies using the James Webb Space Telescope to measure the detailed IMF <initial mass function> down to the low-mass regime, combined with ALMA’s ability to probe the physical properties of the parent molecular gas, will be crucial to deepening our understanding of star formation in low-metallicity environments,” the authors conclude.

• Press Release: In ancient stellar nurseries, some stars are born of fluffy clouds
• Research: ALMA 0.1 pc View of Molecular Clouds Associated with High-mass Protostellar Systems in the Small Magellanic Cloud: Are Low-metallicity Clouds Filamentary or Not?

The post Fluffy Molecular Clouds Formed Stars in the Early Universe appeared first on Universe Today.

Let’s dive into one of those cosmic curiosities that’s bound to blow your mind: how we might chat with aliens. And no, I’m not talking about elaborate coded messages or flashy signals. We’re talking about something incredibly fundamental—21cm radiation.

If you’re planning on having a conversation across the vastness of space, using light waves (electromagnetic radiation) is pretty much your go-to option. It’s fast, reliable, and, well, it’s the most practical way to shout out to other civilizations in the universe. But why specifically 21 centimeters? That’s where things get juicy.

This 21cm radiation isn’t just some random frequency we picked out of a hat. It’s tied to something very essential, known as the hydrogen spin flip. Hydrogen atoms consist of one proton and one electron, and these tiny particles have a property called “spin.” Think of spin like a little arrow pointing up or down. Every so often, in the vast reaches of space, a hydrogen atom’s electron can flip its spin, going from a state where its spin is aligned with the proton to one pointing in the opposite direction. This flip releases energy in the form of radiation at—you guessed it—a wavelength of 21 centimeters.

So, why does this matter? Well, any smart civilization, whether they have blue skin, tentacles, or something more bizarre, will eventually discover hydrogen, understand spin, dabble in quantum mechanics, and figure out this whole 21cm radiation thing. They’ll call it something different (they won’t have “21” or “cm”) but the concept remains universal. It’s like the cosmic Rosetta Stone.

What makes 21cm radiation perfect for long-distance interstellar chats is its ability to cut through interstellar dust. Space is filthy, with dust clouds that block out other forms of light. However, 21cm waves are like the VIPs of the universe, slipping through the velvet ropes of cosmic debris to carry their message far and wide.

Here’s a fun fact: NASA’s Pioneer spacecraft, launched in the early 1970’s, carry plaques. On these plaques there’s a handy diagram of the hydrogen spin flip transition. All other measurements on the plaque, including the height of humans, are made in reference to this fundamental distance. So the hope is that aliens can recognize the hydrogen spin-flip transition and use that to unlock the rest of our message.

Now imagine this scenario: One day, astronomers on Earth detect an unusual surge of 21cm radiation. It’s not coming from a random hydrogen cloud; it’s directional, purposeful. That could very well be an alien civilization sending us a “What’s up?” across the cosmos – 21cm radiation makes for a great calling card.

Using 21cm radiation to communicate with extraterrestrial beings leverages a basic, universal constant. And who knows? Maybe one day, when we finally hear that signal, we’ll know that somewhere out there, another intelligent species figured out the same galactic hack we did.

So keep your eyes—or rather, your telescopes—peeled. The next big discovery could be just a spin flip away!

The post If You’re Going to Call Aliens, Use This Number appeared first on Universe Today.

The majority of the universe remains unmapped, but we have a potential window into it through a peculiar light emitted by nothing other than neutral hydrogen.

Before stars and galaxies lit up the universe, the cosmos was a dark place filled mostly with neutral hydrogen. This was right after the Big Bang and the formation of the CMB—Cosmic Microwave Background. The CMB is like a baby picture of the universe when it was just 380,000 years old. But what came next was a long period called the “Dark Ages.” During this time, the universe didn’t have much going on in terms of visible light because there were no stars or galaxies yet. Frustratingly, most of the volume of the visible universe exists in these Dark Ages, which makes it a very valuable resource to learn about the nature of dark matter and dark energy. But…it was dark, so we can’t just make a bigger telescope and observe it.

Thankfully, the neutral hydrogen that filled the universe during this epoch does emit a feeble kind of light. Due to the quantum mechanical spin flip transition, neutral hydrogen emits radiations with a wavelength of 21 centimeters. However, the Dark Ages were so long ago at this 21cm radiation is redshifted to a wavelength of two meters or more, putting it firmly in the radio band of the electromagnetic spectrum.

In fact, a tiny fraction of the static you hear in your car radio is due to this ancient radiation.

Astronomers can use slightly different wavelengths to map out the extent and evolution of the Dark Ages. Different pockets of neutral gas will emit their radiation at different times, which will correspond to different redshifts.

We expect to see an enormous amount of 21cm radiation at the very longest wavelengths, right at the beginning of the Dark Ages. That’s when the universe was filled with an almost uniform distribution of neutral hydrogen. Then as the first stars and galaxies wake up, they ionize their surrounding gas with powerful blasts of high-energy radiation. So a 21cm map of this era should show holes and pockets in the overall signal. Finally, once most of the neutral hydrogen is wiped away and confined only to cool regions of galaxies, we should see the signal disappear – only to be replaced with the light of galaxies themselves.

However, observing this radiation is a daunting task. That’s because humans are also quite fond of radio emissions, and this signal from the Dark Ages is at least a million times weaker than terrestrial radio broadcasts. Observatories around the world, like the Murchison Wide-field Array in Western Australia and the Hydrogen Epoch of Reionization Array in South Africa have so far failed to find a conclusive signal.

To nail this detection and open up the Dark Ages to exploration, we may have to go off planet. The Lunar Crater Radio Telescope hopes to turn the far side of the Moon into a pristine radio observatory, using the Moon itself to shield the observatory from radio interference. The idea is a long way off, but it might be our only way to to draw a complete map of the cosmos’ past, present, and future.

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NASA engineers are pressing ahead with preparations for the Artemis II mission unless someone tells them otherwise. The ambitious flight will send four astronauts on a trajectory similar to Apollo 8’s historic lunar journey, with the crew traveling around the Moon in an Orion Capsule before returning to Earth. A crucial milestone in the mission preparations was reached as technicians completed the assembly of the Space Launch System’s twin solid rocket boosters inside the Vehicle Assembly Building. The stacking process began in late November 2024 and concluded on February 19th.

In a significant step forward for our return to the Moon, NASA engineers at Kennedy Space Center have finished assembling the massive solid rocket boosters that will power the Artemis II mission. The stacking operation, completed on 19 February 2025, marks a key milestone in preparation for the first crewed lunar mission since Apollo. As someone who never saw the Apollo Moon landings, I’m excited. 

Aldrin on the Moon. Astronaut Buzz Aldrin walks on the surface of the moon near the leg of the lunar module Eagle during the Apollo 11 mission. Mission commander Neil Armstrong took this photograph with a 70mm lunar surface camera. While astronauts Armstrong and Aldrin explored the Sea of Tranquility region of the moon, astronaut Michael Collins remained with the command and service modules in lunar orbit. Image Credit: NASA

The assembly process began on 20 November 2024, inside Kennedy’s amazing Vehicle Assembly Building (VAB), where generations of Moon rockets have been built. Using techniques that have been refined over decades of spaceflight experience, technicians employed one of the facility’s overhead cranes to carefully position each segment of the twin boosters.

These solid rocket boosters represent modern engineering at its best, being assembled on Mobile Launcher 1, a huge structure standing 380 feet tall – roughly the height of a 38-story building. This launch platform serves a number of different functions, acting as both the assembly base for the Space Launch System (SLS) rocket and Orion spacecraft, and the launch platform from which the mission will eventually depart for the Moon.

NASA’s Space Launch System (SLS) rocket with the Orion spacecraft aboard is seen at sunset atop the mobile launcher at Launch Pad 39B as preparations for launch continue, Wednesday, Aug. 31, 2022, at NASA’s Kennedy Space Center in Florida. Credit: (NASA/Joel Kowsky)

The completed boosters will form part of the most powerful rocket ever built by NASA, more powerful even than Saturn V that took Apollo astronauts to the Moon. When ignited, these twin rockets will generate millions of pounds of thrust, working in together with the SLS core stage to lift the Orion spacecraft and its four-person crew toward the Moon.

Apollo 11 launch using the Saturn V rocket

Artemis II represents a historic moment in space exploration as the first time humans will venture beyond low Earth orbit since 1972. The mission profile calls for a crew of four astronauts to journey around the Moon in the Orion spacecraft, testing critical systems and procedures before future missions attempt lunar landings.

The successful completion of booster stacking demonstrates the expertise of NASA’s engineering teams. Each segment had to be perfectly aligned and secured, with no room for error in a process that demands accuracy. The boosters will eventually help propel the spacecraft to speeds exceeding 17,000 miles per hour – fast enough to break free of Earth’s gravity and get to the Moon.

With this milestone achieved, NASA continues toward launch, carefully checking and testing each system to ensure the safety of the crew and the success of this ambitious mission to return humans to deep space.

Moon, here we come, once again. 

Source : Artemis II Rocket Booster Stacking Complete

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It’s not uncommon for space missions to be tested here on planet Earth. With the plethora of missions that have been sent to Mars it  is becoming increasingly likely that the red planet was once warmer, wetter and more habitable than it is today. To find evidence of this, a new paper proposes that Deception Island in Antarctica is one of the best places on Earth to simulate the Martian environment. The paper identifies 30 sites on the island that correspond well to places on Mars.

The exploration of Mars has been a focus of space agencies worldwide, driven by the desire to understand the its geology, climate, possibility of past life, and excitingly the potential for future human colonisation. Early missions, such as NASA’s Mariner 4 in 1965, provided the first close-up images of Mars, while the Viking landers of the 1970s conducted the first successful surface experiments. In the 1990s and 2000s, orbiters like Mars Global Surveyor and rovers like Spirit and Opportunity helped us to understand more about the Martian terrain and atmospheric conditions. As we explore the red planet, and with more projects on the horizon, Mars remains a key target for exploration. 

Three Generations of Mars Rovers in the ‘Mars Yard’ at the Jet Propulsion Laboratory. The Mars Pathfinder Project (front) landed the first Mars rover – Sojourner – in 1997. The Mars Exploration Rover Project (left) landed Spirit and Opportunity on Mars in 2004. The Mars Science Laboratory Curiosity rover landed on Mars in August 2012. Credit: NASA/JPL-Caltech.

The world that has been revealed following the multitude of missions is of a surface that is cold, dry, and exposed to high radiation. Evidence exists that liquid water once flowed on Mars, bringing the tantalising possibility that microbial life may have existed in the past. Today, underground water reserves and seasonal methane emissions hint at the possibility of present-day life BUT and it is a strong BUT, no evidence has been found yet.   Further exploration is required and it is at times like this that researchers turn to planetary analogues to explore further. 

Image taken by the Viking 1 orbiter in June 1976, showing Mars thin atmosphere and dusty, red surface. Credits: NASA/Viking 1

A planetary analogue is a location on Earth that is similar or identical to places found on alien worlds. In the case of Mars, a new paper has been published that suggests that Deception Island in Antarctica is a great ‘analogue’ for parts of Mars. Exploring life that is found in these locations enables us to better understand the locations on Mars and helps inform future exploration. 

The paper, that was authored by a team led by María Angélica Leal Leal identifies 30 locations on the island that are an excellent match for locations on Mars. The locations have been divided into four categories; geologically similar to areas of Mars, environmental conditions are similar to Mars, biological interest due to the existence of extremophiles on Earth and various engineering applications enabling hardware testing in Mars-like environment. 

It concludes that Deception Island in Antarctica serves as a valuable Mars analogue site due to the combination of extreme environmental conditions and geological features that mirror those found on Mars. It’s a volcanic island too offering a natural (and significantly closer) laboratory where it might reveal how life adapts to harsh conditions including low temperatures and high radiation. 

The island’s particularly unique features include the presence of perchlorate (chemical compounds that contain salts made up of chlorine and oxygen atoms,) glaciovolcanic processes, permafrost, and microbial mats (layers of complex microorganisms) that survive in extreme conditions. This all makes for an excellent terrestrial alternative for studying potential past or present life on Mars. However, the researchers note that further detailed studies of the island’s geochemistry, extremophile organisms, and mission simulations are needed to fully confirm its validity as a Mars analogue for specific Martian regions and time periods.

Source : The potential of Deception Island, Antarctica, as a multifunctional Martian analogue of astrobiological interest

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Some of our Solar System’s moons have become very enticing targets in the search for life. There’s growing evidence that some of them have oceans under layers of ice and that these oceans are warm and rich in prebiotic chemistry. NASA’s Europa Clipper is on its way to examine Jupiter’s moon Europa, and the ESA’s Jupiter Icy Moons Explorer is also on its way to the Jovian system to explore some of its icy moons.

While the presence of an ocean on Europa is becoming widely accepted, there’s more uncertainty about the other Galilean moons. However, new evidence suggests that Callisto is very likely an ocean moon, too.

Callisto is Jupiter’s second-largest moon, the third-largest moon in the Solar System, and the outermost Galilean moon. The Voyager probes gave us our first close looks at Callisto in 1979, and the Galileo spacecraft gave us our best images and science data during flybys between 1996 and 2001. Galileo provided the first evidence that Callisto may harbour a subsurface ocean.

Callisto has a different appearance than other suspected ocean moons like Europa and Saturn’s Enceladus. Europa clearly has a white, icy surface, although it has other brownish colours, too. Enceladus has an extremely bright, icy surface and has the highest albedo of any object in the Solar System. Callisto, on the other hand, has a dark, icy surface and is covered in craters.

Europa (L), Enceladus (M), and Callisto (R) have distinctly different surfaces, yet all likely have subsurface oceans.

However, the evidence for its ocean is unrelated to its surface appearance and any visible ice.

The main evidence supporting an ocean on Callisto comes from the moon’s magnetic field. Unlike Earth’s internally generated magnetic field, Callisto’s is induced. That means the field is created from Callisto’s interactions with Jupiter and its extremely powerful magnetic field. For Callisto to induce a magnetic field, it has to have a layer of conductive material.

This illustration shows Jupiter’s powerful magnetic field and the four Galilean moons. Image Credit: ESA.
Licence: ESA Standard Licence

The question is, is the layer an ocean or something else?

Different researchers have been trying to answer that question since Galileo gathered its data. One of the spacecraft’s instruments was a magnetometer, a type called a Dual-Technique Magnetometer (DTM). There are multiple types of magnetometers, and each one works differently. Galileo’s DTM provided redundancy and allowed for cross-checking, which increased the accuracy and reliability of its data. It was especially good at detecting the subtle magnetic fields of Jupiter’s moons, including Callisto. It also collected data continuously, which let scientists gain insights into how the magnetic fields of Jupiter and its moons varied over time due to different interactions.

In a 2017 paper, researchers pointed to the ionosphere as the primary cause of Callisto’s magnetic fields. “We find that induction within Callisto’s ionosphere is responsible for a significant part of the observed magnetic fields,” the authors wrote. “Ionospheric induction creates induced magnetic fields to some extent similar as expected from a subsurface water ocean.”

New research in AGU Advances based on Galileo data strengthens the idea that Callisto has a subsurface ocean and that it’s responsible for the moon’s magnetic field rather than its ionosphere. The paper is titled “Stronger Evidence of a Subsurface Ocean Within Callisto From a Multifrequency Investigation of Its Induced Magnetic Field.” The lead author is Corey Cochrane, a scientist at JPL who studies planetary interiors and geophysics. An important part of this research is that they considered data from multiple Galileo flybys (C03, C09, and C10).

“Although there is high certainty that the induced field measured at Europa is attributed to a global-scale subsurface ocean, there is still uncertainty around the possibility that the induced field measured at Callisto is evidence of an ocean,” Cochrane and his co-researchers write. “This uncertainty is due to the presence of a conductive ionosphere, which will also produce an induction signal in response to Jupiter’s strong time-varying magnetic field.”

Observations acquired from the Galileo spacecraft indicate that Callisto (left) reacts inductively to Jupiter’s (right) time-varying magnetic field. New research suggests that this reaction and its results are indicative of the moon hosting a subsurface salty ocean. Image Credit: Corey J. Cochrane, NASA/JPL-Caltech

In short, Callisto’s magnetic field could be caused by its ionosphere, an ocean, or a combination of both. The problem is that Callisto’s conductive ionosphere creates a magnetic field that can mask the presence of an ocean. To get to the truth, the authors used previously published simulations of the moon’s interactions combined with “both an inverse and an ensemble forward modeling method.” The authors write that this brings some clarity about the possible range of Callisto’s interior properties.

The researchers created a four-layer model of Callisto, including its ionosphere. “Among these models, we vary the thickness of the ice shell, the thickness of the ocean, and the conductivity,” the authors write. They also varied the seafloor depth and the ionosphere’s conductance.

This schematic diagram from the study shows the variable parameters in some of the researchers’ modelling. (Left) D is seafloor depth, T is ocean thickness, and Rc is conductance. (R) The ocean parameter space in the study has 8 linear steps for ocean thickness and 10 steps for ocean conductivity. Image Credit: Cochrane et al. 2025.

The researchers concluded that the moon’s ionosphere alone cannot explain the magnetic field. Instead, it “more likely arises from the combination of a thick conductive ocean and an ionosphere rather than from an ionosphere alone.”

They also concluded that the ocean is tens of kilometres thick from the seafloor to the ice shell, and the ice shell could also be tens of kilometres thick. “As our results demonstrate, both the inverse and forward modelling approaches support the presence of an ocean when considering data acquired from flyby C10 alongside C03 and C09,” the researchers explain. “Our analysis, the first to simultaneously fit C03, C09, and C10 flyby data together, favours the presence of a thick and deep ocean within Callisto.”

The models also favour a thick ice shell “consistent with Callisto’s heavily cratered geology,” they explain.

Galileo wasn’t dedicated to studying Callisto, so there is a dearth of data in all research into its magnetic fields. “It is challenging to place tighter constraints on the properties of Callisto’s ocean because of the limited number of close Galileo flybys that produced reliable data and because of the uncertainty associated with the plasma interaction,” the authors write in their conclusion.

Better and more complete data is in the future, though. Both NASA’s Europa Clipper and the ESA’s JUICE mission will gather more data, some of it from very close to Callisto’s surface.

The Europa Clipper is scheduled to make nine flybys of Callisto. Seven will be within 1800 km of the surface, and four of those will be within 250 km. Its magnetometer will operate continuously during those flybys. The ESA’s JUICE mission is scheduled to perform 21 flybys of Callisto. All of them will be within 7000 km of the surface, and most will be below 1000 km.

The Europa Clipper’s elliptical orbit will allow it to perform flybys of Jupiter’s moons, including Callisto. Image Credit: NASA/JPL-Caltech

Both the Europa Clipper and JUICE have instruments that Galileo didn’t have. Though Galileo came within about 1100 km of Callisto’s surface, it simply could not provide the same kind of data that these newer missions will. The Clipper and JUICE are scheduled to reach the Jovian system in 2030 and 2031, respectively.

As their data starts to arrive and reaches scientists, we will likely determine for sure if Callisto is yet another of the Solar System’s ocean moons.

• Press Release: Jupiter’s Moon Callisto Is Very Likely an Ocean World
• Research: Stronger Evidence of a Subsurface Ocean Within Callisto From a Multifrequency Investigation of Its Induced Magnetic Field

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Gateway’s HALO module heads to the U.S., on its long path to orbiting the Moon.

Preparations for Lunar Gateway are starting to come together. Thales Alenia Aerospace engineers recently began a series of checks on the HALO (Habitation Logistics Outpost) core module. Currently at the company’s Turin, Italy facility, the module is set to head to the U.S. to contractor Northrop Grumman’s Gilbert, Arizona site next month, aboard an Antonov AN-124-100 aircraft.

The HALO segment is the crucial core of what will become Lunar Gateway. Along with environmental and stress tests, the Thales Alenia team will install valves, carry out leak checks, and prepare for integrating secondary structures with HALO. One airlock, the Emirates Crew and Science Module was built and provided by the United Arab Emirates’ Mohammed bin Rashid Space Centre. The airlock will be used for space walks outside of Gateway. In exchange, the UAE will receive an astronaut slot on an Artemis expedition.

The first welding of the ring and cylinder segments for HALO occurred at Thales Alenia Space in 2021, marking the first major milestone for assembly of the module’s primary structure.

The HALO core module on the move. Credit: Thales Alenia Space.

Northrop Grumman was awarded the $935 million dollar contract to develop the Gateway HALO module in 2021. NASA’s FY2025 budget allocates over $817 million for the continued construction of Gateway.

Looking inside the HALO module. Credit: Thales Alenia Space. What’s Next for HALO and Gateway

“To ensure all flight hardware is ready to support Artemis IV—the first crewed mission to Gateway—NASA is targeting the launch of HALO and the Power and Propulsion Element no later than December 2027,” Laura Rochon (NASA-Johnson Spaceflight Center) told Universe Today in a recent email. “These modules will launch together aboard a SpaceX Falcon Heavy rocket and spend about a year traveling uncrewed to lunar orbit, while providing scientific data on solar and deep space radiation during transit.”

Once the module arrives at Northrop Grumman’s Arizona facility, it will undergo more tests and integration with the propulsion stage prior to launch. As one of four pressurized modules, HALO will support crew, experiments and internal and external payloads. Gateway will serve as a staging point, supporting lunar research and crews on the surface. One big advantage for Gateway is that it would act as a reusable ‘command module’ for expeditions to the Moon, allowing for longer stays on the surface.

Part of the propulsion element for Gateway. Credit: NASA/JSC/Maxar Space Systems. A Deep Space Station

Like the International Space Station, Gateway is an international effort. The European Space Agency is designing its Lunar Link (part of ESA’s larger LunaNet DTN framework initiative) for the station. The Canadian Space Agency (CSA) is supplying a robotic arm, its Small Orbital Replacement Unit Robotic Interface. Gateway will be approximately a fifth the size and volume of the ISS. Unlike the permanently crewed ISS, Gateway will only host temporary expeditions, and will spend much on its time vacant and running in autonomous mode.

An artist’s conception of Gateway in orbit around the Moon. Credit: NASA-JSC.

“The ISS has been a cornerstone of space research in low-Earth orbit for more than two decades,” says Rochon. “Gateway expands this legacy into the deep space environment. Gateway will operate in orbit around the Moon, where radiation is a greater concern due to lack of a protective shield. It took 40 launches and over 13 years to build the ISS. Gateway will be fully constructed in four launches using advanced technology and capabilities focused on what is needed to support long-term human lunar exploration.”

Science and research will still happen on Gateway… even when humans are absent. “Gateway will focus on pushing the boundaries of remote and autonomous operations,” says Rochon. “This will enable Gateway to conduct science investigation and support missions, even when crew are not present.”

Putting Gateway together. Credit: NASA. Artemis at a Crossroads

This all happens at a time of change and uncertainty for NASA. A layoff of 1,000 employees announced earlier this week was put on hold…for now. Many pundits have also questioned the burgeoning complexity and cost overruns for the Artemis initiative, and if Gateway is still needed.

NASA’s large Space Launch System (SLS) rocket finally got off the ground with Artemis I in November 2022. The first crewed lunar flyby on Artemis II has been pushed back to April 2026. The first lunar landing mission on Artemis III relies heavily on SpaceX’s Starship Heavy and Starship HLS (Human Landing System) as part of its architecture. Starship has another suborbital launch coming up on February 26th. The first possible orbital flight of Starship is planned for this April. SpaceX still has lots of hurdles to overcome prior to the Artemis III lunar landing, set for 2027.

Gateway will orbit the Moon in a unique, Near-rectilinear halo orbit (NRHO). This unique type of orbit is necessary for astronauts to access the entirety of the lunar surface. This is especially true for a landing in the south polar regions. The Cis-Lunar Autonomous Positioning System Technology Operations Navigations Experiment (CAPSTONE) mission launched in 2022 on a Rocket Lab Electron rocket is pioneering this type of orbit. An NRHO path also affords the station a near-continuous line-of-sight communications link with controllers on Earth.

Despite the hurdles it faces, it would be great to finally see humans living and working around the Moon. Imagine the view! For now, we can watch as the pieces come together, and the core HALO module for Gateway takes ‘one small step’ closer to the launch pad.

The post Lunar Gateway’s Core HALO Module Enters the Clean Room appeared first on Universe Today.

What if I told you there was a secret window, and if you looked through this window you could see the entire history of the universe unfold before your very eyes?

It sounds too good to be true. But this is science, and if we’ve learned anything in our four centuries of scientific exploration of nature, its that science can produce miracles. Or in this case, science can take advantage of nature’s own miracles.

I’m talking about a curious little feature of the humble hydrogen atom. One proton, one electron. Done, the simplest atom possible. You can throw a neutron in there if you’re feeling generous. It’s not necessary but adds a little bit of fiber.

Now this proton and this electron are particles, which means they have a list of properties, like mass and charge. Those properties tell us how the particles respond to the gravitational force and the electric force. And then there’s this other property, a property we call spin. When I say “spin” everybody, including myself, thinks of the obvious: something spinning, like a Harlem globetrotter spinning a basketball on their pinky finger. But these are particles, which means they take up no volume in space, so how do they…spin?

The answer is they don’t. But they kind of do. It’s really weird and complicated and it’s one of those many quantum things that we just have to learn to live with, because there’s no getting around it and quantum mechanics doesn’t really care if we understand it or not. The spin of a particle refers to, essentially, how it responds to magnetic fields. If you were to take a metal ball and charge it up with electricity, and then set it spinning and throw it into a magnetic field, there’s a natural response of that spinning metal charged ball to the magnetic field. If it’s spinning one way, the ball gets deflected in one direction. If it’s spinning the other way, it goes the other way.

Particles like electrons and protons do that: they respond to magnetic fields exactly as if they were charged metal balls. They’re not, but they still act like they are, so we call it spin because that’s the closest thing we can call this, and we have to move on.

And particles like protons and electrons can have one of two choices for their spin. We call these choices up and down, because when we shoot these particles through a magnetic field that points up-and-down, the up-pointing particles go up and the down-spinning particles go down. We could have called these spin states left and right or a and b or alice and bob, but we went with up and down.

In a hydrogen atom, the electron and proton can either have the same direction of spin (both up or both down) or they can have opposite spins. For various quantum mechanical reasons having to do with overlap of the wavefunctions, when the proton and electron have the exact same spin, that configuration has ever so slightly more energy than the situation than when they’re the opposite.

That means that when they find themselves in that same-spin situation, because quantum mechanics allows all sorts of randomness like that, they can realign themselves to reach a lower energy state.

This takes a long time. If you found a hydrogen atom all by its lonesome in the middle of empty space with parallel spins, and you waited and watched for it to flip back to its normal configuration, the average wait time is around 11 million years.

But here’s the kicker. Last time I checked there are way more than 11 million hydrogen atoms in the universe, which means if you have a whole bunch of hydrogen atoms all sitting around, chances are one of them is going to realign and release that pent-up energy.

And if you have, say, a galaxy’s worth of hydrogen atoms, then they’re emitting this energy pretty much all the time.

Now it’s not a lot of energy, around 5.8 micro electron-volts. That energy comes out in a very specific way, in the form of a single photon of electromagnetic radiation. And we can compute the wavelength of that radiation, and that comes out to 21 cm.

Every galaxy is glowing in this very special kind of light, all thanks to the humble hydrogen atom.

The post How Humble Hydrogen Lights Up the Universe appeared first on Universe Today.

Every Martian year (which last 686.98 Earth days), the Red Planet experiences regional dust storms that coincide with summer in the southern hemisphere. Every three Martian years (five and a half Earth years), these storms grow so large that they encompass the entire planet and are visible from Earth. These storms are a serious hazard for robotic missions, causing electrostatic storms that can mess with electronics and cause dust to build up on solar panels. In 2018 and 2022, the Opportunity Rover and InSight Lander were lost after dust storms prevented them from drawing enough power to remain operational.

But what about crewed missions? In the coming decades, NASA and the Chinese Manned Space Agency (CMS) plan to send astronauts and taikonauts to Mars. These missions will include months of surface operations and are expected to culminate in the creation of long-duration habitats on the surface. According to new research by the Keck School of Medicine at the University of Southern California (USC), Martian dust storms can potentially cause respiratory issues and elevated risk of disease, making them yet another health hazard space agencies need to prepare for.

The research was led by Justin L. Wang, a Doctor of Medicine at USC, along with several of his colleagues from the Keck School of Medicine. They were joined by researchers from the UCLA Space Medicine Center, the Ann and HJ Smead Department of Aerospace Engineering and the Laboratory for Atmospheric and Space Physics at UC Boulder, and the Astromaterials Acquisition and Curation Office at NASA’s Johnson Space Center. The paper detailing their findings appeared on February 12th in the journal GeoHealth.

Sending crewed missions to Mars presents many challenges, including logistics and health hazards. In the past 20 years, the shortest distance between Earth and Mars was 55 million km (34 million miles), or roughly 142 times the distance between the Earth and the Moon. This was in 2003 and was the closest the two planets had been in over 50,000 years. Using conventional methods, it would take six to nine months to make a one-way transit, during which time astronauts will experience physiological changes caused by long-term exposure to microgravity.

These include muscle atrophy, loss of bone density, a weakened cardiovascular system, etc. Moreover, a return mission could last as long as three years, during which time astronauts would spend at least a year living and working in Martian gravity (36.5% that of Earth). There’s also the risk of elevated radiation exposure astronauts will experience during transits and while operating on the surface of Mars. However, there are also the potential health effects caused by exposure to Martian regolith. As Wang described to Universe Today via email:

“There are many potential toxic elements that astronauts could be exposed to on Mars. Most critically, there is an abundance of silica dust in addition to iron dust from basalt and nanophase iron, both of which are reactive to the lungs and can cause respiratory diseases. What makes dust on Mars more hazardous is that the average dust particle size on Mars is much smaller than the minimum size that the mucus in our lungs is able to expel, so they’re more likely to cause disease.”

During the Apollo Era, the Apollo astronauts reported how lunar regolith would stick to their spacesuits and adhere to all surfaces inside their spacecraft. Upon their return to Earth, they also reported physical symptoms like coughing, throat irritation, watery eyes, and blurred vision. In a 2005 NASA study, the reports of six of the Apollo astronauts were studied to assess the overall effects of lunar dust on EVA systems, which concluded that the most significant health risks included “vision obscuration” and “inhalation and irritation.”

Artist’s depiction of a dust storm on Mars. Credit: NASA

“Silica directly causes silicosis, which is typically considered an occupational disease for workers that are exposed to silica (i.e., mining and construction),” said Wang. “Silicosis and exposure to toxic iron dust resemble coal worker’s pneumoconiosis, which is common in coal miners and is colloquially known as black lung disease.”

Beyond causing lung irritation and respiratory and vision problems, Martian dust is known for its toxic components. These include perchlorates, silica, iron oxides (rust), gypsum, and trace amounts of toxic metals like chromium, beryllium, arsenic, and cadmium – the abundance of which is not well understood. On Earth, the health effects of exposure to these metals have been studied extensively, which Wang and his team drew upon to assess the risk they pose to astronauts bound for Mars in the coming decades:

“It’s significantly more difficult to treat astronauts on Mars for diseases because the transit time is significantly longer than other previous missions to the ISS and the Moon. In this case, we need to be prepared for a wide array of health problems that astronauts can develop on their long-duration missions. In addition, [microgravity and radiation] negatively impact the human body, can make astronauts more susceptible to diseases, and complicate treatments. In particular, radiation exposure can cause lung disease, which can compound the effects that dust will have on astronauts’ lungs.”

In addition to food, water, and oxygen gas, the distance between Earth and Mars also complicates the delivery of crucial medical supplies, and astronauts cannot be rushed back to Earth for life-saving treatments either. According to Wang and his colleagues, this means that crewed missions will need to be as self-sufficient as possible when it comes to medical treatment as well. As with all major health hazards, they emphasize the need for prevention first, though they also identify some possible countermeasures to mitigate the risks:

“Limiting dust contamination of astronaut habitats and being able to filter out any dust that breaks through will be the most important countermeasure. Of course, some dust will be able to get through, especially when Martian dust storms make maintaining a clean environment more difficult. We’ve found studies that suggest vitamin C can help prevent diseases from chromium exposure and iodine can help prevent thyroid diseases from perchlorate.”

Austin Langton, a researcher at NASA’s Kennedy Space Center in Florida, creates a fine spray of the regolith simulant BP-1. Credits: NASA/Kim Shiflett

They also stressed that these and other potential countermeasures need to be taken with caution. As Wang indicated, taking too much vitamin C can increase the risk of kidney stones, which astronauts are already at risk for after spending extended periods in microgravity. In addition, an excess of idione can contribute to the same thyroid diseases that it is meant to treat in the first place. For years, space agencies have been actively developing technologies and strategies to mitigate the risks of lunar and Martian regolith.

Examples include special sprays, electron beams, and protective coatings, while multiple studies and experiments are investigating regolith to learn more about its transport mechanisms and behavior. As the Artemis Program unfolds and missions to Mars draw nearer, we are likely to see advances in pharmacology and medical treatments that address the hazards of space exploration as well.

Further Reading: GeoHealth

The post Should Astronauts Be Worried About Mars Dust? appeared first on Universe Today.

If Intermediate-Mass Black Holes (IMBHs) are real, astronomers expect to find them in dwarf galaxies and globular clusters. There’s tantalizing evidence that they exist but no conclusive proof. So far, there are only candidates.

The Dark Energy Spectroscopic Instrument (DESI) has found 300 additional candidate IMBHs.

Logic says that IMBHs should exist. We know of stellar-mass black holes, and we know of supermassive black holes (SMBHs). Stellar-mass black holes have between five and tens of solar masses, and SMBHs have at least hundreds of thousands of solar masses. Their upper limit is not constrained. Astrophysicists think these black holes are linked in an evolutionary sequence, so it makes sense that there’s an intermediate step between the two. That’s what IMBHs are, and their masses should range from about 100 to 100 thousand solar masses. IMBHs could also be relics of the very first black holes to form in the Universe and the seeds for SMBHs.

The problem is that there are no confirmed instances of them.

Omega Centauri, the brightest globular cluster in the Milky Way, is one of the prime candidates for an IMBH. There’s an ongoing scientific discussion about the cluster and the potential IMBH in its center. Stars in the cluster’s center move faster than other stars, indicating that a large mass is present. Some scientists think it’s an IMBH, while others think it’s a cluster of stellar-mass black holes.

This is Omega Centauri, the largest and brightest globular cluster that we know of in the Milky Way. An international team of astronomers used more than 500 images from the NASA/ESA Hubble Space Telescope spanning two decades to detect seven fast-moving stars in the innermost region of Omega Centauri. These stars provide compelling new evidence for the presence of an intermediate-mass black hole. Image Credit: ESA/Hubble & NASA, M. Häberle (MPIA)

Other evidence for IMBHs comes from a gravitational wave detection in 2019. The wave was generated by two black holes merging. The pair of black holes had masses of 65 and 85 solar masses, and the resulting black hole had 142 solar masses. The other 8 solar masses were radiated away as gravitational waves.

By adding 300 more IMBH candidates to the list, DESI may be nudging us toward a definitive answer about the existence of these elusive black holes.

The 300 new candidates are presented in a paper soon to be published in The Astrophysical Journal. It’s titled “Tripling the Census of Dwarf AGN Candidates Using DESI Early Data” and is available at arxiv.org. The lead author is Ragadeepika Pucha, a postdoctoral researcher at the University of Utah.

The 300 candidate IMBHs are the largest collection to date. Until now, there were only 100 to 150 candidates. This is a massive leap in the amount of available data, and future research will no doubt rely on it to make progress on the IMBH issue.

“Our wealth of new candidates will help us delve deeper into these mysteries, enriching our understanding of black holes and their pivotal role in galaxy evolution.”

Ragadeepika Pucha, University of Utah

The new candidates were identified in DESI’s early data release, which contains data from 20% of DESI’s first year of operations. The data included more than just IMBH candidates. DESI also found about 115,000 dwarf galaxies and spectra from about 410,000 galaxies, a huge number.

This mosaic shows a series of images featuring candidate dwarf galaxies hosting an active galactic nucleus, captured with the Subaru Telescope’s Hyper Suprime-Cam. Image Credit: Legacy Surveys/D. Lang (Perimeter Institute)/NAOJ/HSC Collaboration/D. de Martin (NSF NOIRLab) & M. Zamani (NSF NOIRLab)

The data allowed lead author Pucha and her colleagues to explore the relationship between the evolution of dwarf galaxies and black holes.

Despite their extreme masses, black holes are difficult to find. Their presence is inferred from their effect on their environment. In their presence, stars are accelerated to high velocities. Fast-moving stars were one of the clues showing that the Milky Way has an SMBH.

Astronomers are pretty certain that all massive galaxies like ours host an SMBH in their centers, but this certainty fades when it comes to dwarf galaxies. Dwarf galaxies are so small that our instruments struggle to observe them in detail. Unless the black hole is actively feeding.

When a black hole is actively consuming material, it is visible as an active galactic nucleus (AGN.) AGNs are like beacons that alert astronomers to the presence of a black hole.

“When a black hole at the center of a galaxy starts feeding, it unleashes a tremendous amount of energy into its surroundings, transforming into what we call an active galactic nucleus,” lead author Pucha said in a press release. “This dramatic activity serves as a beacon, allowing us to identify hidden black holes in these small galaxies.”

The team found 2,500 dwarf galaxies containing an active galactic nucleus, an astonishing number. Like the new IMBH candidates, this is the largest sample ever discovered. The researchers determined that 2% of the dwarf galaxies hosted AGN, a big step up from the 0.5% gleaned from other studies.

“This increase can be primarily attributed to the smaller fibre size of DESI compared to SDSS <Sloan Digital Sky Survey>, which aids with the identification of lower luminosity AGN within the same magnitude and redshift range,” the authors explain in their paper.

This artist’s illustration depicts a dwarf galaxy that hosts an active galactic nucleus — an actively feeding black hole. In the background are many other dwarf galaxies hosting active black holes, as well as a variety of other types of galaxies hosting intermediate-mass black holes. Image Credit: NOIRLab/NSF/AURA/J. da Silva/M. Zamani

Astronomers think that black holes found in dwarf galaxies should be within the intermediate-mass range. However, only 70 of the newly discovered IMBH candidates overlap with dwarf AGN candidates. This is unexpected and raises yet more questions about black holes, how they form, and how they evolve within galaxies.

This scatter plot, adapted from the research, shows the number of candidate dwarf galaxies hosting active galactic nuclei (AGN) from previous surveys compared with the number of new dwarf galaxy AGN candidates discovered by the Dark Energy Spectroscopic Instrument (DESI). Image Credit: NOIRLab/NSF/AURA/R. Pucha/J. Pollard

“For example, is there any relationship between the mechanisms of black hole formation and the types of galaxies they inhabit?” Pucha said. “Our wealth of new candidates will help us delve deeper into these mysteries, enriching our understanding of black holes and their pivotal role in galaxy evolution.”

DESI is only getting started. These discoveries were made with only a small portion of data from the instrument’s first year of operation, and there are several more years of operation to come.

“The anticipated increase in the sample of dwarf AGN candidates over the next five years with DESI will accelerate studies of AGN in dwarf galaxies,” the authors write in their research. “The statistical sample of dwarf AGN candidates will be invaluable for addressing several key questions related to galaxy evolution on the smallest scales, including accretion modes in low-mass galaxies and the co-evolution of galaxies and their central BHs,” they conclude.

• Press Release: DESI Uncovers 300 New Intermediate-Mass Black Holes Plus 2500 New Active Black Holes in Dwarf Galaxies
• Research: Tripling the Census of Dwarf AGN Candidates Using DESI Early Data
• Research: Properties and Astrophysical Implications of the 150 M? Binary Black Hole Merger GW190521
• Research: New constraints on the central mass contents of Omega Centauri from combined stellar kinematics and pulsar timing

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