You are here

News Feeds

Astronomers Will Get Gravitational Wave Alerts Within 30 Seconds

Universe Today Feed - Fri, 04/26/2024 - 5:38pm

Any event in the cosmos generates gravitational waves, the bigger the event, the more disturbance. Events where black holes and neutron stars collide can send out waves detectable here on Earth. It is possible that there can be an event in visible light when neutron stars collide so to take advantage of every opportunity an early warning is essential. The teams at LIGO-Virgo-KAGRA observatories are working on an alert system that will alert astronomers within 30 seconds fo a gravity wave event. If warning is early enough it may be possible to identify the source and watch the after glow. 

The very fabric of space-time can be thought of as a giant celestial ocean. Any movement within the ocean will generate waves. The same is true of movements and disturbances in space, causing a compression in one direction while stretching out in the perpendicular direction. Modern gravity wave detectors are usually L-shaped with beams shining down each arm of the building. The two beams are combined and the interference patterns are studied allowing the lengths of the two beams to be accurately calculated. Any change suggests the passage of a gravity wave. 

LIGO Observatory

A team of researchers at the University of Minnesota have run a study that endeavours to improve the detection of the waves. Not only do they hope to improve the detection itself but also to establish an alerting mechanism so that astronomers get a notification within 30 seconds after the event detection. 

The team used data from previous observations and created simulated gravity wave signal data so that they could test the system. But it is far more than just an alerting system. Once fully operational, it will be able to detect the shape of the signals, track how it evolves over time and even provide an estimate of the properties of the individual components that led to the waves. 

After it is fully operational, the software would detect the wave for example from neutron star or black hole collisions. The former usually too faint to be able to detect unless its location is known precisely. It would generate an alert from the wave to help precisely pinpoint the location giving an opportunity for follow up study. 

Light bursts from the collision of two neutron stars. Credit: NASA’s Goddard Space Flight Center/CI Lab

There are still many outstanding questions surrounding neutron star and black hole formation not least of which is the exact mechanism that leads to the formation of gold and uranium. 

graThe LIGO (Laser Interferometer Gravitational-Wave Observatory) has just finished its latest run but the next is due in February 2025. Between recent observing runs, enhancements and improvements have been made to improve the capability of detecting signals. Eventually of course it comes down to the data and once the current run ends, the teams will get started. 

Source : Researchers advance detection of gravitational waves to study collisions of neutron stars and black holes

The post Astronomers Will Get Gravitational Wave Alerts Within 30 Seconds appeared first on Universe Today.

Categories: Science

Next Generation Ion Engines Will Be Extremely Powerful

Universe Today Feed - Fri, 04/26/2024 - 2:02pm

During the Space Race, scientists in both the United States and the Soviet Union investigated the concept of ion propulsion. Like many early Space Age proposals, the concept was originally explored by luminaries like Konstantin Tsiolkovsky and Hermann Oberth – two of the “forefathers of rocketry.” Since then, the technology has been validated repeatedly by missions like the Deep Space-1 (DS-1) technology demonstrator, the ESA’s Smart-1 lunar orbiter, JAXA’s Hayabusa and Hayabysa 2 satellites, and NASA’s Dawn mission.

Looking to the future of space exploration, researchers at the NASA Glenn Research Center (GRC) have been busy developing a next-generation ion engine that combines extreme fuel efficiency with high acceleration. These efforts have led to the NASA-H71M sub-kilowatt Hall-effect thruster, a small spacecraft electric propulsion (SSEP) system that will enable new types of planetary science missions. With the help of commercial partners like SpaceLogistics, this thruster will also be used to extend the lifetimes of spacecraft that are already in orbit.

Space exploration and commercial space have benefitted from the development of small spacecraft and small satellites. These missions are notable for being cost-effective since they require less propellant to launch, can be deployed in smarms, and take advantage of rideshares. Similarly, the proliferation of small satellite constellations in Low Earth Orbit (LEO) has made low-power Hall-effect thrusters the most common electric propulsion system in space today. These systems are noted for their fuel efficiency, allowing many years of orbital maneuvers, corrections, and collision avoidance.

Nevertheless, small spacecraft will need to be able to perform challenging propulsive maneuvers like achieving escape velocity, orbital capture, and other maneuvers that require significant acceleration (delta-v). The thrust required to perform these maneuvers – 8 km/s (~5 mps) of delta-v – is beyond the capability of current and commercially available propulsion technology. Moreover, low-cost commercial electric propulsion systems have limited lifetimes and typically process only about 10% of a small spacecraft’s propellant mass.

Similarly, secondary spacecraft are becoming more common thanks to rockets with excess capacity (enabling rideshare programs). Still, these are generally limited to scientific targets that align with the primary mission’s trajectory. Additionally, secondary missions typically have limited time to collect data during high-speed flybys. What is needed is an electric propulsion system that requires low power (sub-kilowatt) and has high-propellant throughout – meaning it is capable of using lots of propellant over its lifetime.

To meet this demand, engineers at NASA Glenn are taking many advanced high-power solar electric propulsion (SEP) elements developed over the past decade and are miniaturizing them. These elements were developed as part of NASA’s Moon to Mars mission architecture, with applications including the Power and Propulsion Element (PPE) of the Lunar Gateway. A SEP system was also part of the design for a Deep Space Transport (DST), the vehicle that will conduct the first crewed missions to Mars by 2040. The NASA-H71M system, however, is expected to have a major impact on small spacecraft, expanding mission profiles and durations.

According to NASA, missions using the NASA-H71M system could operate for 15,000 hours and process over 30% of the small spacecraft’s initial mass in propellant. This system could increase the reach of secondary spacecraft, allowing them to deviate from the primary mission’s trajectory and explore a wider range of scientific targets. By allowing spacecraft to decelerate and make orbital insertions, this technology could increase mission durations and the amount of time they have to study objects.

NASA-H71M Hall-effect thruster on the Glenn Research Center Vacuum Facility 8 thrust stand (left) and Dr. Jonathan Mackey tuning the thrust stand before closing and pumping down the test facility (right). Credit: NASA GRC

It’s also beyond the needs of most commercial LEO missions, and the associated costs are generally higher than what commercial missions call for. As such, NASA continues to seek partnerships with commercial developers working on small commercial spacecraft with more ambitious mission profiles. One such partner is SpaceLogistics, a wholly owned subsidiary of Northrop Grumman that provides in-orbit satellite servicing to geosynchronous satellite operators using its proprietary Mission Extension Vehicle (MEV).

This vehicle relies on Northrop Grumman NGHT-1X Hall-effect thrusters based on the NASA-H71M design. This propulsive capability will allow the MEV to reach satellites in Geosynchronous Earth Orbit (GEO), where it will dock with customer’s satellites, extending their lives for at least six years. Through a Space Act Agreement (SAA), Northrop Grumman is conducting long-duration wear tests (LDWT) at NASA Glenn’s Vacuum Facility 11. The first three MEP spacecraft are expected to launch in 2025 and extend the lives of three GEO communication satellites.

Further Reading: NASA

The post Next Generation Ion Engines Will Be Extremely Powerful appeared first on Universe Today.

Categories: Science

Computer scientists unveil novel attacks on cybersecurity

Computers and Math from Science Daily Feed - Fri, 04/26/2024 - 1:52pm
Researchers have found two novel types of attacks that target the conditional branch predictor found in high-end Intel processors, which could be exploited to compromise billions of processors currently in use.
Categories: Science

Neutron Stars Could be Capturing Primordial Black Holes

Universe Today Feed - Fri, 04/26/2024 - 1:48pm

The Milky Way has a missing pulsar problem in its core. Astronomers have tried to explain this for years. One of the more interesting ideas comes from a team of astronomers in Europe and invokes dark matter, neutron stars, and primordial black holes (PBHs).

Astronomer Roberto Caiozzo, of the International School for Advanced Studies in Trieste, Italy, led a group examining the missing pulsar problem. “We do not observe pulsars of any kind in this inner region (except for the magnetar PSR J1745-2900),” he wrote in an email. “This was thought to be due to technical limitations, but the observation of the magnetar seems to suggest otherwise.” That magnetar orbits Sagittarius A*, the black hole at the core of the Milky Way.

An x-ray map of the core of the Milky Way showing the position of the recently discovered magnetar orbiting the supermassive black hole Sgr A*. Courtesy Chandra and XMM-Newton.

The team examined other possible reasons why pulsars don’t appear in the core and looked closely at matnetar formation as well as disruptions of neutron stars. One intriguing idea they examined was the cannibalization of primordial black holes by neutron stars. The team explored the missing-pulsar problem by asking the question: could neutron star-primordial black hole cannibalism explain the lack of detected millisecond pulsars in the core of the Milky Way? Let’s look at the main players in this mystery to understand if this could happen.

Neutron Stars, Pulsars, and Little Black Holes, Oh My

Theory suggests that primordial black holes were created in the first seconds after the Big Bang. “PBHs are not known to exist,” Caiozzo points out, “but they seem to explain some important astrophysical phenomena.” He pointed at the idea that supermassive black holes seemed to exist at very early times in the Universe and suggested that they could have been the seeds for these monsters. If there are PHBs out there, the upcoming Nancy Grace Roman Telescope could help find them. Astronomers predict they could exist in a range of masses, ranging from the mass of a pin to around 100,000 the mass of the Sun. There could be an intermediate range of them in the middle, the so-called “asteroid-mass” PBHs. Astronomers suggest these last ones as dark matter candidates.

Primordial black holes, if they exist, could have formed by the collapse of overdense regions in the very early universe. Credit M. Kawasaki, T.T. Yanagida.

Dark matter makes up about 27 percent of the Universe, but beyond suggesting that PBH could be part of the dark matter content, astronomers still don’t know exactly what it is. There does seem to be a large amount of it in the core of our galaxy. However, it hasn’t been directly observed, so its presence is inferred. Is it bound up in those midrange PBHs? No one knows.

The third player in this missing pulsar mystery is neutron stars. They’re huge, quivering balls of neutrons left over after the death of a supergiant star of between 10 and 25 solar masses. Neutron stars start out very hot (in the range of ten million K) and cool down over time. They start out spinning very fast and they do generate magnetic fields. Some emit beams of radiation (usually in radio frequencies) and as they spin, those beams appear as “pulses” of emission. That earned them the nickname “pulsar”. Neutron stars with extremely powerful magnetic fields are termed “magnetars”.

Pulsars are fast-spinning neutron stars that emit narrow, sweeping beams of radio waves. A new study identifies the origin of those radio waves. NASA’s Goddard Space Flight Center The Missing Pulsar Problem

Astronomers have searched the core of the Milky Way for pulsars without much success. Survey after survey detected no radio pulsars within the inner 25 parsecs of the Galaxy’s core. Why is that? Caizzo and his co-authors suggested in their paper that magnetar formation and other disruptions of neutron stars that affect pulsar formation don’t exactly explain the absence of these objects in the galactic core. “Efficient magnetar formation could explain this (due to their shorter lifetime),” he said, “But there is no theoretical reason to expect this. Another possibility is that the pulsars are somehow disrupted in other ways.”

Usually, disruption happens in binary star systems where one star is more massive than the other and it explodes as a supernova. The other star may or may not explode. Something may kick it out of the system altogether. The surviving neutron star becomes a “disrupted” pulsar. They aren’t as easily observed, which could explain the lack of radio detections.

If the companion isn’t kicked out and later swells up, its matter gets sucked away by the neutron star. That spins up the neutron star and affects the magnetic field. If the second star remains in the system, it later explodes and becomes a neutron star. The result is a binary neutron star. This disruption may help explain why the galactic core seems to be devoid of pulsars.

Using Primordial Black Hole Capture to Explain Missing Pulsars

Caizzo’s team decided to use two-dimensional models of millisecond pulsars—that is, pulsars spinning extremely fast—as a way to investigate the possibility of primordial black hole capture in the galactic core. The process works like this: a millisecond pulsar interacts in some way with a primordial black hole that has less than one stellar mass. Eventually, the neutron star (which has a strong enough gravitational pull to attract the PBH) captures the black hole. Once that happens, the PBH sinks to the core of the neutron star. Inside the core, the black hole begins to accrete matter from the neutron star. Eventually, all that’s left is a black hole with about the same mass as the original neutron star. If this occurs, that could help explain the lack of pulsars in the inner parsecs of the Milky Way.

Could this happen? The team investigated the possible rates of capture of PBHs by neutron stars. They also calculated the likelihood that a given neutron star would collapse and assessed the disruption rate of pulsars in the galactic core. If not all the disrupted pulsars are or were part of binary systems, then that leaves neutron star capture of PBHs as another way to explain the lack of pulsars in the core. But, does it happen in reality?

Missing Pulsar Tension Continues

It turns out that such cannibalism cannot explain the missing pulsar problem, according to Caizzo. “We found that in our current model PBHs are not able to disrupt these objects but this is only considering our simplified model of 2 body interactions,” he said. It doesn’t rule out the existence of PHBs, only that in specific instances, such capture isn’t happening.

So, what’s left to examine? If there are PHBs in the cores and they’re merging, no one’s seen them yet. But, the center of the Galaxy is a busy place. A lot of bodies crowd the central parsecs. You have to calculate the effects of all those objects interacting in such a small space. That “many-body dynamics” problem has to account for other interactions, as well as the dynamics and capture of PBHs.

Astronomers looking to use PBH-neutron star mergers to explain the lack of pulsar observations in the core of the Galaxy will need to better understand both the proposed observations and the larger populations of pulsars. The team suggests that future observations of old neutron stars close to Sgr A* could be very useful. They’d help set stronger limits on the number of PBHs in the core. In addition, it would be useful to get an idea of the masses of these PBHs, since those on the lower end (asteroid-mass types) could interact very differently.

For More Information

Revisiting Primordial Black Hole Capture by Neutron Stars
Searching for Pulsars in the Galactic Centre at 3 and 2 mm

The post Neutron Stars Could be Capturing Primordial Black Holes appeared first on Universe Today.

Categories: Science

5 extraordinary ideas about the mind and what it means to be conscious

New Scientist Feed - Fri, 04/26/2024 - 9:00am
To celebrate the launch of our new event series in the US, kicking off with a masterclass on the brain and consciousness, we have unlocked five incredible long reads
Categories: Science

Rare mutation that causes short stature may shed light on ageing

New Scientist Feed - Fri, 04/26/2024 - 9:00am
The genetic variant, which causes people to be insensitive to growth hormone, may also protect people from heart disease
Categories: Science

Alpacas are the only mammals known to directly inseminate the uterus

New Scientist Feed - Fri, 04/26/2024 - 8:00am
When alpacas mate, males deposit sperm directly into the uterus, a reproductive strategy not confirmed in any other mammals
Categories: Science

Japan’s Lunar Lander Survives its Third Lunar Night

Universe Today Feed - Fri, 04/26/2024 - 7:22am

Space travel and exploration was never going to be easy. Failures are sadly all too common but it’s wonderful to see missions exceed expectations. The Japanese Space Agency’s SLIM lunar lander was only supposed to survive a single day but it’s survived three brutal, harsh lunar nights and is still going. The temperatures plummet to -170C at night and the lander was never designed to operate into the night. Even sat upside down on the surface it’s still sending back pictures and data. 

The Japanese agency’s lunar lander known as SLIM (Smart Lander for Investigating the Moon) began its lunar journey on 19 January 2024 when it touched down on the surface of the Moon. Its mission was to test the lunar landing technology and to collect data about the surface geology. 

An artist’s conception shows Japan’s SLIM lander in its upended position on the lunar surface. (Credit: JAXA)

Unfortunately, soon after landing it became clear that the probe had landed at a strange angle, leaning forwards, resting on its face. The orientation of the solar panels was all wrong and it meant they could not generate as much electricity as expected allowing it to operate for a few hours just after dawn and just before sunset. 

Of course it is important to note that a day on the Moon lasts many days compared to a day here on Earth and so, the first night for SLIM began on 31 January. Surprisingly, SLIM survived the first long night where temperatures to -170 degrees. SLIM was never designed to survive the cold harsh nights on the Moon so it was with some surprise that it powered back up successfully on the 15 February. 

The operations team for SLIM were disbanded in March but to their surprise, after the second lunar night, a signal was received again. Surpassing everyones expectations it seems SLIM wasn’t going to give up yet and still sending images. The lander was even picked up after its second night by cameras on board the Chandrayaan-2 orbiter as it flew over. 

Just a few days ago on Wednesday 24 January, JAXA, the Japanese Aerospace Exploration Agency announced it had survived a third night on the freezing lunar surface. Using the plucky littler lander which measures just 1.5m x 1.5m x 2m, the agency hope to be able to learn more about the origin of the Moon by analysing the surface geology.

One of the fascinating elements to the mission was the pinpoint landing technology that was being tested. On descent, the lander would be able to recognise the craters using technology that has been developed by facial recognition systems. Using the data, it would be able to determine its location with pinpoint accuracy and perform a touch down with an accuracy of 100m. The landing was successfully accurate albeit slightly wobbly leaving the lander in a strange orientation. 

source : Japan’s moon lander wasn’t built to survive a week long lunar night. It’s still going after 3

The post Japan’s Lunar Lander Survives its Third Lunar Night appeared first on Universe Today.

Categories: Science

Asteroid that broke up over Berlin was fastest-spinning one ever seen

New Scientist Feed - Fri, 04/26/2024 - 6:00am
Before it shattered over Germany, the asteroid 2024 BX1 was clocked rotating once every 2.6 seconds – the fastest spin we have observed
Categories: Science

The Physics of Flocks

neurologicablog Feed - Fri, 04/26/2024 - 4:58am

Most people have watched large flocks of birds. They are fascinating, and have interested scientists for a long time. How, exactly, do so many birds maintain their cohesion as a flock? It’s obviously a dynamic process, but what are the mechanisms?

When I was young I was taught that each flock had a leader, and the other birds were ultimately just following that leader. When two smaller flocks combined into a larger flock, then one of those leaders become dominant and takes over the combined flock. But this explanation is largely untrue. It actually depends a great deal on the species of bird and the type of flock.

The “follow the leader” method is essentially what is happening with the V formations. These are obviously very different from the murmurations of small birds morphing like a giant flying amoeba. Some species, like pigeons, use a combined strategy, still following a leader, but more of a hierarchy of leaders, which can change over time.

For the more dynamic flocks, like starlings, researchers found that there is no leader or hierarchy. Every bird is just following the flock itself. It is a great example of an emergent phenomenon in nature. It’s like ants working in a colony or a bee hive – each individual bee or ant does not really know what the entire colony is doing, and there is no leader or foreman calling the shots or directing traffic. Each individual is just following a simple algorithm, and the collective complexity emerges from that.

What, then, is the algorithm that the birds are using to generate flocking behavior?  Going back to the pre and early scientific era, naturalists actually speculated that these large bird flocks used some form of direct communication – even raising the possibility of bird telepathy. But it does not appear that birds are communicating with each other, and there is no telepathy, bird or otherwise. By the 1980s, using computer simulations and high-speed camera observations, scientists started to formulate the rules of large flocks. It seems that flocking behavior can emerge from three simple bird behaviors. 

First, each bird tries to avoid collisions with all its neighbors. Second, each bird will be attracted to other birds of the same species. And third, each bird will fly in the same general direction as the rest of the flock. Scientists discovered other rules for special situations. For example, when a predator attacks, individual birds try to fly toward the middle of the group for protection.

While these rules produce a reasonable approximation of large bird flocks, it was also clear this was not the entire answer. There is another layer here, other than just bird behavioral algorithms. That layer is the physics of flight and aerodynamics. A recent study looks at flow dynamics of flocking behavior, adding some additional insight into the behavior of flocks. They used mechanical birds in water to test the effects of the flow of fluid of each bird’s flying, and how that affects other birds in the flock.

For small groups, flow dynamics will tend to push birds into an optimal aerodynamic pocket. This is like drafting, and we already knew that birds do this. Those V formations are all about optimizing this effect to make flying more efficient. In the case of more dynamic flocks, the flow dynamics act like little springs, keeping each bird in the right place and avoiding collisions. If a bird gets out of line, the air flow will tend to push them back into place.

This makes the behavioral algorithm even simpler – you don’t have to simultaneously follow the flock while avoiding collisions. You just have to follow the path of least resistance, and if you stray you will be pushed back into place.

However, the researchers also found that when flocks get larger and larger, the flow dynamics change, creating more vortices and turbulence. These increase in a cascading effect from the front of the flock back, and eventually would lead to birds crashing into each other. It doesn’t seem like the researchers completely solved this problem, but they did show one possible solution. If you introduce a little variability into the behavior of each bird (so they are not perfectly in position) then this will tend to disrupt the amplification of turbulent flow, allowing for larger flocks without collisions.

Perhaps this is how bird flocking behavior evolved. First behavioral algorithms allowed for small flocks for mutual protection and warning from predators. And then evolutionary tweaks to the bird behavior algorithms allowed for larger and larger flocks over evolutionary time. And of course this only happened in some species. Others evolved other flocking behavior, or not flocking behavior depending on where they were in the predator-prey dynamic.

Still it seems like there is more to learn about large bird flocks, which at this point appears to be a dynamic interaction between behavior and physics. This is both more complex and more elegant than the quaint notions of the past.

The post The Physics of Flocks first appeared on NeuroLogica Blog.

Categories: Skeptic

Global warming could make tides higher as well as raising sea levels

New Scientist Feed - Fri, 04/26/2024 - 4:00am
In addition to the overall rise in sea level, the heights of tides are also changing as the oceans warm and separate into more distinct layers
Categories: Science

Science-Based Satire: More Parents Turn to Kinesiology Diapers for Fussy Infants

Science-based Medicine Feed - Fri, 04/26/2024 - 4:00am

Are parents really turning to diapers made using kinesiology tape to help their fussy babies? Of course not. That would be incredibly silly, and profitable. This is satire.

The post Science-Based Satire: More Parents Turn to Kinesiology Diapers for Fussy Infants first appeared on Science-Based Medicine.
Categories: Science

Black Holes Can Halt Star Formation in Massive Galaxies

Universe Today Feed - Fri, 04/26/2024 - 3:14am

It’s difficult to actually visualise a universe that is changing. Things tend to happen at snails pace albeit with the odd exception. Take the formation of galaxies growing in the early universe. Their immense gravitational field would suck in dust and gas from the local vicinity creating vast collections of stars. In the very centre of these young galaxies, supermassive blackholes would reside turning the galaxy into powerful quasars. A recent survey by the James Webb Space Telescope (JWST) reveals that black holes can create a powerful solar wind that can remove gas from galaxies faster than they can form into stars, shutting off the creation of new stars.

To remove the confusion and mystique around black holes, they are the corpse of massive stars. When supermassive stars collapse at the end of their lives their core turns into a point source that is so incredibly dense that even light, travelling at 300,000 kilometres per second, is unable to escape. It’s believed that many galaxies have supermassive black holes at their core. 

Swift scene change to the earlier part of the life of a star. Fusion in the core generates incredible amounts of energy as new elements are synthesised. Along with new elements, heat and light, a powerful outflow of electrically charged particles rushes away and permeates the surrounding space. Here in our Solar System, charged particles rush Earthward and on arrival we experience the glorious display of the northern lights. 

Visualization of the solar wind encountering Earth’s magnetic “defenses” known as the magnetosphere. Clouds of southward-pointing plasma are able to peel back layers of the Sun-facing bubble and stack them into layers on the planet’s nightside (center, right). The layers can be squeezed tightly enough to reconnect and deliver solar electrons (yellow sparkles) directly into the upper atmosphere to create the aurora. Credit: JPL

A team of astronomers using the JWST have found that, over 90 percent of the wind that flows through a distant galaxy is made of neutral gas and to date, has been invisible. Until recently it was only possible to detect ionised gas – gas which carries an electric charge – which is warm. The neutral gas in the study revealed that neutral gas was cold but JWST was able to detect it. 

The powerful outflow of neutral gas is thought to come from the supermassive blackholes at the core of some galaxies at the edge of the Universe. The team, led by Dr Rebecca Davies from Swinburne University first identified that black hole driven outflow in a distant galaxy over 10 billion light years away. The paper published in Nature explains how ‘The outflow is removing gas faster than gas is being converted into stars, indicating that the outflow is likely to have a very significant impact on the evolution of the galaxy.’

With a lack of gas and dust, star formation will slow and eventually stop. Just like a forest that always has new trees growing to replace old, dying trees, so galaxies usually have star formation to replace dying stars. Ultimately the forest, and a galaxy will be unable to grow and develop and eventually become static and slowly die with the final stars blinking out. 

This is a JWST view of the Crab Nebula. Like other supernovae, a star exploded to create this scene.The result is a rapidly spinning neutron star (a pulsar) at its heart, surrounded by material rushing out from the site of the explosion. SN 2022jli could have either a neutron star or a black hole orbiting with a companion star.

The team found that the active galactic nuclei with supermassive black holes are the driving force behind this outflow of gas. Those with the most massive black holes can even strip the host galaxy of all the star forming gasses playing a major role in the evolution of the galaxy. 

Source : New JWST observations reveal black holes rapidly shut off star formation in massive galaxies

The post Black Holes Can Halt Star Formation in Massive Galaxies appeared first on Universe Today.

Categories: Science

Snazzy New Store Items

Skeptoid Feed - Fri, 04/26/2024 - 2:00am

Get the snazzy new Skeptoid Hydro Flask tumbler or radical new Skeptoid coffee mug. Both are engraved so they’ll never fade. Now available at the Skeptoid store at Skeptoid.com.

Categories: Critical Thinking, Skeptic

Deepfake politicians may have a big influence on India’s elections

New Scientist Feed - Fri, 04/26/2024 - 1:00am
Political campaigns are deploying AI-generated deepfake versions of politicians to reach hundreds of millions of eligible voters in India’s 2024 election – the world’s largest ever
Categories: Science

Bedbug Bedlam: Real Infestation or Social Panic in Paris?

Skeptic.com feed - Fri, 04/26/2024 - 12:00am

Bedbugs. Just mention of the word is enough to give people the heebie-jeebies and send shivers down their spines—or start scratching. Beginning in early fall of 2023 and coinciding with Paris Fashion Week from September 25 to October 3, fear of the unhealthy vermin swept across Paris. There does not appear to be one incident that triggered the scare, but once the cry of “Bedbug!” went up, it quickly went viral online and in the Parisian media. A wave of YouTube and TikTok videos showed the proliferous pests crawling on bus seats, in trains, riding the subways, lounging at Charles de Gaulle airport, and taking in the latest plays in Paris theatre district the “Grands Boulevards.” Some anxious residents even refused to sit during their daily commutes. One British newspaper saw the humorous side of the panic, carrying the headline: “Coming Soon to a Cinema Near You? The Return of the Bud Bug.”1

Within days, the humble bedbug Cimex lectularius was being portrayed as public enemy No. 1. Politicians began holding press conferences on “the bedbug crisis” and vowing action. By September 29, the Deputy Mayor of Paris, Emmanuel Grégoire, ominously posted on X/Twitter: “No one is safe.”2 One MP, Ms. Mathilde Panot, carried a test tube filled with bedbugs into the French Parliament, complaining that pesky parasites were “making the lives of millions of our fellow citizens a living hell.”3

While they may give people the creeps, bedbugs are more of an annoyance than a major health threat. These small, reddish-brown insects have an affinity for feeding on the blood of humans as they sleep. During the day they love to hide in the cracks and crevices of headboards, box springs, mattresses, and bed frames next to their human prey, hence the name. According to the Mayo Clinic, they are not considered to be a serious health issue as they do not directly spread disease, although they can trigger allergic reactions and skin conditions, and scratching the bites can lead to infection.4

Bonne nuit. Dormez bien.
Ne laissez pas les punaises de lit piquer.

Most experts agree that there does appear to be an uptick in the bedbug population of Paris—and in many parts of the world. According to estimates from the French national pest control association, the number of calls to exterminators jumped about 10 percent over last year. However, this was not surprising as it corresponds with the spike in travel after the Covid pandemic.5 There is also evidence that bedbugs have become more resistant to insecticides while the rise in global temperatures have boosted their sex lives.6, 7 But a 10 percent increase hardly qualifies as a massive infestation.

Look closer, and all is not as it seems.

Thibault Buckley who works for a French company that specializes in dealing with bedbugs that have infested dogs, says that most of recent cases have turned out to be unrelated to bedbugs.8 The issue is also nothing new. For instance, a government survey of French households between 2017 and 2022 found that 11 percent were infested with the creepy critters.9 The French bedbug scare has also spread the fear of infestations to other European metropolitan areas. However, bedbugs have long been a feature, if a very unwanted one, of most major cities. What is new is the sudden media attention.

Soon after hearing of the bedbug infestation, Lebanese dermatologist Zeina Nehme happened to be on a trip to Paris when she decided to spend her weekend finding some of the tiny troublemakers and making a social media video about it. That’s when something odd happened: she could not locate a single bug—not in her apartment or the restaurants she visited or the vast rail network, the Paris Metro. “I actively searched to find one to take pics and do the reel. Nothing,” she said.10

This article appeared in Skeptic magazine 29.1
Buy print edition
Buy digital edition
Subscribe to print edition
Subscribe to digital edition
Download our app

The Paris bedbug “invasion” has the hallmarks of a social panic involving a real or imagined threat. In this case, the threat is real—there are bedbugs and their numbers have been increasing, but their presence has been exaggerated. Bugs are a common feature of everyday life. Now however, in the wake of sensational media reports of invading bedbugs, people have begun to scrutinize their surroundings for evidence for the critters. In the past a bus or train traveler may have sat next to one and not paid much notice. These days, Parisians are hyperaware of any bug, especially while on public transport or in public places like the cinema—and people are seeing them everywhere.

One factor likely driving the scare is misidentifications. Bedbugs are often mistaken for other insects such as cockroach nymphs, which look similar but are slightly longer and more cylindrical, and also with fleas, ticks, or carpet beetles.11 Another factor leading to the perceived invasion of bedbugs, may be embarrassment—or a lack thereof. Until recently, if someone found the creepy crawlers in their home, it was not exactly a badge of honor and they may have been reluctant to mention it to their work colleagues around the watercooler. Now, with the surge in media interest, it appears to be chic to report finding the bugs and exchange war stories with fellow Parisians.

Goodnight. Sleep tight.
Don’t let the bedbugs bite.

About the Author

Robert E. Bartholomew is an Honorary Senior Lecturer in the Department of Psychological Medicine at the University of Auckland in New Zealand. He has written numerous books on the margins of science covering UFOs, haunted houses, Bigfoot, lake monsters—all from a perspective of mainstream science. He has lived with the Malay people in Malaysia, and Aborigines in Central Australia. He is the co-author of two seminal books: Outbreak! The Encyclopedia of Extraordinary Social Behavior with Hilary Evans, and Havana Syndrome with Robert Baloh.

References
  1. https://bit.ly/48FilZQ
  2. https://bit.ly/48dCEhg
  3. https://bit.ly/3RMPGLw
  4. https://bit.ly/48EaR9z
  5. https://bit.ly/3vm8ZEh
  6. https://bit.ly/41KXORl
  7. https://bit.ly/3tush9X
  8. https://bit.ly/3H5NKJk
  9. https://bit.ly/3vnhnmT
  10. https://bit.ly/3S4GYdh
  11. https://bit.ly/3ve397C
Categories: Critical Thinking, Skeptic

Two medicines for opioid addiction also help with compulsive gambling

New Scientist Feed - Thu, 04/25/2024 - 11:00pm
The medicines nalmefene and naltrexone helped compulsive gamblers reduce their betting activities, trials have shown
Categories: Science

Mapping the Milky Way’s Magnetic Field in 3D

Universe Today Feed - Thu, 04/25/2024 - 3:09pm

We are all very familiar with the concept of the Earth’s magnetic field. It turns out that most objects in space have magnetic fields but it’s quite tricky to measure them. Astronomers have developed an ingenious way to measure the magnetic field of the Milky Way using polarised light from interstellar dust grains that align themselves to the magnetic field lines. A new survey has begun this mapping process and has mapped an area that covers the equivalent of 15 times the full Moon. 

Many people will remember experiments in school with iron filings and bar magnets to unveil their magnetic field. It’s not quite so easy to capture the magnetic field of the Milky Way though. The new method to measure the field relies upon the small dust grains which permeate space between the stars. The grains of dust are similar in size to smoke particles but they are not spherical. Just like a boat turning itself into the current, the dust particles’ long axis tends to align with the local magnetic field. As they do, they emit a glow in the same frequency as the cosmic background radiation and it is this that astronomers have been tuning in to. 

Infrared image of the shockwave created by the massive giant star Zeta Ophiuchi in an interstellar dust cloud. Credit: NASA/JPL-Caltech; NASA and The Hubble Heritage Team (STScI/AURA); C. R. O’Dell, Vanderbilt University

Not only do the particles glow but they also absorb starlight that passes through them just like polarising filters. The polarisation of light is familiar to photographers that might use polarising filters to darken skies and manage reflections. The phenomenon of polarisation refers to the propagation of light. As it moves through a medium it carries energy from one place to another but on the way it displays wave like characteristics. The wave nature is made up of alternating displacements of the medium through which they are travelling (imagine a wave in water). The displacement is not always the same as the direction of travel; sometimes it is parallel and at other times it is perpendicular. In polarisation, the displacement is limited to one direction only. 

In the particles in interstellar space, the polarising properties capture the magnetic field and polarise the light that travels through them revealing the details of the magnetic field. Just as they are on Earth, magnetic field lines are of crucial importance to galactic evolution. They regulate star formation, shape the structure of a galaxy and like gigantic galactic rivers, shape and direct the flow fo gas around the galaxy. 

Researchers from the Inter-University Institute for High Energies in Belgium used the PASIPHAE survey – an international collaboration to explore the magnetic field from the polarisation in interstellar dust – to start the process. They measured the polarisation of more than 1500 stars which covered an area of the sky no more than 15 times the size of the full Moon. The team then used data from the Gaia astrometry satellite and a new algorithm to map the magnetic fields in the galaxy in that part of the sky. 

This is the first time that any large scale project has attempted to map the gravitational field of the Milky Way. It will take some time to complete the full mapping but it when complete it will provide great insight not just into the magnetic field of galaxies but to the evolution of galaxies across the universe. 

Source : A first glimpse at our Galaxy’s magnetic field in 3D

The post Mapping the Milky Way’s Magnetic Field in 3D appeared first on Universe Today.

Categories: Science

Swarm of nanorobots can remove tiny plastic fragments from water

New Scientist Feed - Thu, 04/25/2024 - 3:00pm
In just 2 hours, small metal robots can capture most nanoscopic plastic particles from a sample of water
Categories: Science

NASA’s New Solar Sail Has Launched and Deployed

Universe Today Feed - Thu, 04/25/2024 - 1:58pm

Solar Sails are an enigmatic and majestic way to travel across the gulf of space. Drawing an analogy to the sail ships of the past, they are one of the most efficient ways of propelling craft in space. On Tuesday a RocketLab Electron rocket launched NASA’s new Advanced Composite Solar Sail System. It aims to test the deployment of large solar sails in low-earth orbit and on Wednesday, NASA confirmed they had successfully deployed a 9 metre sail. 

In 1886 the motor car was invented. In 1903 humans made their first powered flight. Just 58 years later, humans made their first trip into space on board a rocket. Rocket technology has changed significantly over the centuries, yes centuries. The development of the rocket started way back in the 13th Century with the Chinese and Mongolians firing rocket propelled arrows at each other. Things moved on somewhat since then and we now have solid and liquid rocket propellant, ion engines and solar sails with more technology in the wings. 

A SpaceX Falcon 9 rocket rises from its Florida launch pad to send Intuitive Machines’ Odysseus moon lander spaceward. (NASA via YouTube)

Solar sails are of particular interest because they harness the power of sun, or star light to propel probes across space. The idea isn’t knew though, Johannes Kepler (of planetary motion fame) first suggested that sunlight could be used to push spacecraft in the 17th Century in his works entitled ‘Somnium’. We had to wait until the 20h Century though before Russian scientist Konstantin Tsiolkovsky outlined the principle of how solar sails might actually work. Carl Sagan and other members of the Planetary Society start to propose missions using solar sails in the 70’s and 80’s but it wasn’t until 2010 that we saw the first practical solar sail vehicle, IKAROS.

Image of the fully deployed IKAROS solar sail, taken by a separation camera. Credit: JAXA

The concept of solar sails is quite simple to understand, relying upon the pressure of sunlight. The sails are angled such that photons strike the reflective sail and bounce off it to push the spacecraft forward. It does of course take a lot of photons to accelerate a spacecraft using light but slowly, over time it is a very efficient propulsion system requiring no heavy engines or fuel tanks. This reduction of mass makes it easier for solar sails to be accelerated by sunlight but the sail sizes have been limited by the material and structure of the booms that support them. 

NASA have been working on the problem with their Next Generation Solar Sail Boom Technology. Their Advanced Composite Solar Sail System uses a CubeSat built by NanoAvionics to test a new composite boom support structure. It is made from flexible polymer and carbon fibre materials to create a stiffer, lighter alternative to existing support structure designs. 

On Wednesday 24 April, NASA confirmed that the CubeSat has reached low-Earth orbit and deployed a 9 metre sail. They are now powering up the probe and establishing ground contract. It took about 25 minutes to deploy the sail which spans 80 square metres. If the conditions are right, it may even be visible from Earth, possibly even rivalling Sirius in brightness. 

Source : Solar Sail CubeSat Has Deployed from Rocket

The post NASA’s New Solar Sail Has Launched and Deployed appeared first on Universe Today.

Categories: Science

Pages

Subscribe to The Jefferson Center  aggregator