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Using 'time travel' to think about technology from the perspective of future generations

Matter and energy from Science Daily Feed - Tue, 03/26/2024 - 9:26am
Researchers have conducted a series of participatory deliberation workshops in which the participants were asked to consider issues of future society and manufacturing, in general, and as they relate to hydrothermally produced porous glass. In workshops where the perspective of 'imaginary future generations' was adopted, participants' perceptions of the technology's feasibility and future potentiality changed significantly.
Categories: Science

Using 'time travel' to think about technology from the perspective of future generations

Computers and Math from Science Daily Feed - Tue, 03/26/2024 - 9:26am
Researchers have conducted a series of participatory deliberation workshops in which the participants were asked to consider issues of future society and manufacturing, in general, and as they relate to hydrothermally produced porous glass. In workshops where the perspective of 'imaginary future generations' was adopted, participants' perceptions of the technology's feasibility and future potentiality changed significantly.
Categories: Science

Flavour-predicting AI can tell brewers how to make beer taste better

New Scientist Feed - Tue, 03/26/2024 - 9:00am
An AI model trained on chemical and perceptual data on 250 Belgian beers can predict the flavour profile of a brew – and how to make it tastier
Categories: Science

The physicist searching for quantum gravity in gravitational rainbows

New Scientist Feed - Tue, 03/26/2024 - 9:00am
Claudia de Rham thinks that gravitons, hypothetical particles thought to carry gravity, have mass. If she’s right, we can expect to see “rainbows” in ripples in space-time
Categories: Science

AI forecaster can predict the future better than humans

New Scientist Feed - Tue, 03/26/2024 - 8:00am
An AI forecaster based on the language model GPT-4 can predict the outcome of future events more accurately than single humans. In some cases, it can even outperform the “wisdom of crowds”
Categories: Science

Merging Stars Can Lead to Blue Supergiants

Universe Today Feed - Tue, 03/26/2024 - 7:56am

In the constellation of Orion, there is a brilliant bluish-white star. It marks the right foot of the starry hunter. It’s known as Rigel, and it is the most famous example of a blue supergiant star. Blue supergiants are more than 10,000 times brighter than the Sun, with masses 16 – 40 times greater. They are unstable and short-lived, so they should be rare in the galaxy. While they are rare, blue supergiants aren’t as rare as we would expect. A new study may have figured out why.

We aren’t entirely sure how these massive stars form, though one idea is that they occur when a massive main sequence star passes through an interstellar cloud. By capturing gas and dust from the cloud, a star can shift off the main sequence to become a blue supergiant. Another idea is that they may form within stellar nurseries with a mass as great as 300 Suns. As a result, they quickly burn so brightly that they never become true main-sequence stars. Both of these models predict that blue supergiants are much more rare than the number we observe.

This new study starts by noting that blue supergiants, particularly the smaller ones known as B-type supergiants, are rarely seen with companion stars. This is odd since most massive stars form as part of a binary or multiple system. The authors propose that B-type blue supergiants aren’t often in binary systems because they typically are the product of binary mergers.

The team simulated a range of models where a giant main-sequence star has a smaller close-orbiting companion and then looked at what would result if the two stars merged. They then compared the results to observations of 59 young blue supergiant stars in the Large Magellanic Cloud. They found that not only can these mergers produce blue supergiants in the mass range of the Magellanic stars, but the spectra of the simulated mergers match the spectra of the 59 blue supergiants. This strongly suggests that many if not most B-type blue supergiants are the result of stellar mergers.

In the future, the team would like to carry this work further to see how blue supergiants evolve into neutron stars and black holes. This could help explain the type of mergers observed by gravitational wave observatories such as LIGO and Virgo.

Reference: Menon, Athira, et al. “Evidence for Evolved Stellar Binary Mergers in Observed B-type Blue Supergiants.” The Astrophysical Journal Letters 963.2 (2024): L42.

The post Merging Stars Can Lead to Blue Supergiants appeared first on Universe Today.

Categories: Science

New method to measure entropy production on the nanoscale

Matter and energy from Science Daily Feed - Tue, 03/26/2024 - 7:39am
Entropy, the amount of molecular disorder, is produced in several systems but cannot be measured directly. A new equation sheds new light on how entropy is produced on a very short time scale in laser excited materials.
Categories: Science

Silicon spikes take out 96% of virus particles

Matter and energy from Science Daily Feed - Tue, 03/26/2024 - 7:39am
An international research team has designed and manufactured a virus-killing surface that could help control disease spread in hospitals, labs and other high-risk environments.
Categories: Science

Tiniest 'starquake' ever detected

Space and time from Science Daily Feed - Tue, 03/26/2024 - 7:39am
An orange dwarf star has yielded the tiniest 'starquakes' ever recorded, measured by an international team of scientists.
Categories: Science

Mathematical innovations enable advances in seismic activity detection

Computers and Math from Science Daily Feed - Tue, 03/26/2024 - 7:39am
Scientists successfully addressed mathematical challenges in conventional Spectral Matrix analysis, used to analyze three-component seismic signals, by introducing time-delay components. The new technique enables the characterization of various polarized waves and the detection of seismic events that have previously gone unnoticed by conventional methods. These findings pave the way for improving a variety of applications, including earthquake detection.
Categories: Science

Scientists on the hunt for evidence of quantum gravity's existence at the South Pole

Matter and energy from Science Daily Feed - Tue, 03/26/2024 - 7:38am
An Antarctic large-scale experiment is striving to find out if gravity also exists at the quantum level. An extraordinary particle able to travel undisturbed through space seems to hold the answer.
Categories: Science

Scientists on the hunt for evidence of quantum gravity's existence at the South Pole

Space and time from Science Daily Feed - Tue, 03/26/2024 - 7:38am
An Antarctic large-scale experiment is striving to find out if gravity also exists at the quantum level. An extraordinary particle able to travel undisturbed through space seems to hold the answer.
Categories: Science

Matthew appears again on a continuing podcast series on the history of DNA

Why Evolution is True Feed - Tue, 03/26/2024 - 7:30am

The Consortium for the History of Science, Technology, and Medicine has now done 13 podcasts on the history of DNA, beginning with the discovery of nucleic acids through the observation that DNA was the hereditary material (Avery et al.) and (so far) up to the structure of the double helix.  As far I know, our own Dr. Cobb, very eloquent behind the microphone, has been on four of these broadcasts:  #3, 4, 7 and the newest one #13, about Watson, Crick, and the double helix.

You can access the whole lot by clicking on this screenshot, or get to the individual podcasts by clicking on the screenshot below.

This podcast series illuminates the history of seminal discoveries and research through which we learned about the molecule that has been dubbed as the “secret of life” itself: DNA, or deoxyribonucleic acid.

This series progresses from the first discovery of the substance in 1869 to the late 1950s, when scientists figured out the structure of this molecule and its implications for the way in which it carries out its biological functions. Each episode features scholars and experts from different fields, including the history of science, other humanities and social sciences—such as philosophy, anthropology, sociology of science and STS—the specific areas of science pertinent to the paper being discussed, and science communication.

Click on the “Resources” tab for information for researchers as well as further readings.

Jump to:
Episode 1 on Friedrich Miescher and the discovery of nuclein
Episode 2 on Albrecht Kossel and the discovery of the building blocks of nuclein
Episode 3 on Walter Sutton and the relation between chromosomes and heredity
Episode 4 on Fred Griffith and the discovery of bacterial transformation
Episode 5 on Phoebus Levene, DNA chemistry and the tetranucleotide hypothesis
Episode 6 on William Astbury, Florence Bell and the first X-ray pictures of DNA
Episode 7 on Oswald Avery, Colin McLeod, and Maclyn McCarty and the chemical basis of bacterial transformation
Episode 8 on Maclyn McCarty, Oswald Avery and the enzymatic evidence for DNA as the transforming substance
Episode 9 on Erwin Chargaff and the evidence for non-uniformity of nucleotide base composition in DNA
Episode 10 on Harriet Ephrussi-Taylor, Rollin Hotchkiss and the demonstration of bacterial transformation as a general phenomenon
Episode 11 on Alfred Hershey, Martha Chase, and the conclusive evidence for the function of DNA as the material of heredity.
Episode 12 on Maurice Wilkins, Rosalind Franklin, their collaborators, and the data that supported the double helix model for DNA structure.
Episode 13 on James Watson, Francis Crick, and the DNA Double Helix.

You can hear the latest episode, 62 minutes long, by clicking at the screenshot below, is described comme ça:

Rounding out the story begun in the previous installment, episode 13 of the DNA Papers centers on the publications in which the double helical structure for DNA was proposed, detailed, and its various implications speculated upon. It features four papers, all by Watson and Crick from Cambridge. Together these papers not only proposed that DNA’s three dimensional structure was a double-stranded helix, but also described the antiparallel and complementary nature of its two component strands and the specific pairing of  the component nucleotide bases, namely,  the purines, A and G, with the  pyrimidines T and C respectively. The papers also discussed the implications of these features for the fundamental functions of DNA. . . .

And the participants are:

Soraya de Chadarevian, University of California, Los Angeles
Matthew Cobb, University of Manchester
Nathaniel Comfort, Johns Hopkins University
Georgina Ferry

Categories: Science

Gaia Finds Ancient Streams of Stars That Formed the Milky Way

Universe Today Feed - Tue, 03/26/2024 - 7:19am

Using ESA’s Gaia spacecraft, astronomers have tracked down two streams of stars that likely formed the foundation of the Milky Way. Named “Shakti and Shiva,” the two streams contain about 10 million stars, all of which are 12 to 13 billion years old and likely came together even before the spiral arms and disk were formed. These star streams are all moving in roughly similar orbits and have similar compositions. Astronomers think they were probably separate galaxies that merged into the Milky Way shortly after the Big Bang.,

“What’s truly amazing is that we can detect these ancient structures at all,” said lead author Khyati Malhan of the Max Planck Institute for Astronomy (MPIA) in Heidelberg, Germany, in an ESA press release. “The Milky Way has changed so significantly since these stars were born that we wouldn’t expect to recognize them so clearly as a group – but the unprecedented data we’re getting from Gaia made it possible.”

Astrometry Data

Gaia uses astrometry — the precise measurements of the positions and movements of stars and other celestial bodies – and is building the largest, most precise three-dimensional map of our Galaxy by surveying nearly two billion objects.

With Gaia’s data, the researchers were able to determine the orbits of individual stars in the Milky Way, as well as determine their content and composition. These ancient stars are all moving in very similar orbits and the structure of the two different star streams stood out because their stars contained a certain chemical composition.

“Shakti and Shiva populations possess an unconventional combination of orbital and abundance properties that have not been observed previously,” the researchers wrote in their paper, published in the Astrophysical journal. 

By compiling very detailed chemical abundance patterns for each, the astronomers determined these stars were the oldest stars in the galaxy, all born before the disc of the Milky Way had formed.

The components of the Milky Way Galaxy. This artist’s impression shows our roughly 13 billon-year-old ‘barred spiral galaxy’ that is home to a few hundred billion stars. Credit: Left: NASA/JPL-Caltech; right: ESA; layout: ESA/ATG medialab.

“The stars there are so ancient that they lack many of the heavier metal elements created later in the Universe’s lifetime,” said co-author Hans-Walter Rix, also of MPIA and the lead ‘galactic archaeologist’ in this research, which began in 2022. “These heavy metals are those forged within stars and scattered through space when they die. The stars in our galaxy’s heart are metal-poor, so we dubbed this region the Milky Way’s ‘poor old heart’. Until now, we had only recognized these very early fragments that came together to form the Milky Way’s ancient heart. With Shakti and Shiva, we now see the first pieces that seem comparably old but located further out. These signify the first steps of our galaxy’s growth towards its present size.”

While the two streams are similar, they aren’t exactly the same. Shakti stars orbit a little further from the Milky Way’s center and in more circular orbits than Shiva stars. The streams are named two divine beings from Hindu philosophy who worked together to create the Universe.

Because of Gaia’s ability to provide data to create incredibly detailed celestial maps, the researchers were able to build a dynamical map of that includes the two star streams plus other known components that have played a role in our galaxy’s formation.

“Revealing more about our galaxy’s infancy is one of Gaia’s goals, and it’s certainly achieving it,” said Timo Prusti, Project Scientist for Gaia at ESA. “We need to pinpoint the subtle yet crucial differences between stars in the Milky Way to understand how our galaxy formed and evolved. This requires incredibly precise data – and now, thanks to Gaia, we have that data. As we discover surprise parts of our galaxy like the Shiva and Shakti streams, we’re filling the gaps and painting a fuller picture of not only our current home, but our earliest cosmic history.”

Further reading:
ESA press release
Paper: Shiva and Shakti: Presumed Proto-Galactic Fragments in the Inner Milky Way

The post Gaia Finds Ancient Streams of Stars That Formed the Milky Way appeared first on Universe Today.

Categories: Science

Heat pumps: How to speed up the switch to low-carbon home heating

New Scientist Feed - Tue, 03/26/2024 - 7:00am
The rollout of heat pumps and other green heating technologies is going far too slowly in the UK – here’s what’s needed to get it moving
Categories: Science

Readers’ wildlife photos

Why Evolution is True Feed - Tue, 03/26/2024 - 6:30am

Today we have photos and videos of Hawaii sent in by Rosemary Alles, with photography credits to both her and Hale Anderson. The text is by Rosemary and is indented; you can enlarge the photos by clicking on them.

Background

Sri Lanka lies in the shadow of her giant neighbor India; a teardrop on the vast slate of the Indian Ocean. My family emigrated from our island nation many moons ago, leaving a jeweled landscape ravaged by corruption, ethnic violence, and terrorism.

My first home in the West was in Canada and then on the Big Island of Hawaii. These days, I travel between South Africa and Hawaii centering my work around the protection of iconic mega-fauna.

Hawaii, like Sri Lanka, is home to a myriad endemic species; many are critically endangered, endangered or threatened. Frequently referred to as the “Endangered Species Capital of the World”, my island state is also home to Hawaii Volcano’s National Park. 344,812 acres of rainforest, desert and windswept magnificence that boasts at least one success story; the nearly flightless Nene Goose. (Branta sandvicensis). This once endangered bird has made a comeback thanks to ongoing funding and restoration efforts.

From Jerry: Here are two photos I took on the Big Island of a nene crossing sign and the goose itself: July 1, 2019.

Last month, my sister and I were on the Big Island of Hawaii memorializing my mother’s passing. While there, Kīlauea erupted, throwing molten rock 35-50 feet in the air. A shield volcano, Kīlauea is the youngest and most active volcano on the Islands. I’ve been close to many lava flows during my years Hawaii, and this time, we were -once again- fortunate to see Kīlauea erupt on September 15th, just hours before it stopped. A video is here.

Before we left, my sister to her home in Toronto, and I to South Africa, we sat by the ocean where the water meets the sand. That evening, as the sea swallowed the sun in a crepuscular ritual, the sky turned red, a fiery blood-orange I had never seen before, not in all my years on the islands.

Mālama ‘Āina. Take care of the land, take care of the sea.

Images of the fiery sunset have not been adjusted at all, other than for cropping.

These are the images of the fiery sunset:

A brief explanation of the phenomena (the vivid nature of the sunset and the detail in the clouds) is explained as follows (by an astronomer-friend in France). Please refer to the two drawings obviously not drawn to scale.

Low hanging clouds are illuminated by the sun from below. The sun has set for the observer (me) but not from the perspective of the clouds. The grazing light enhances the contrast. Essentially the light from the sun is reflecting at a low angle on the clouds causing grazing.

The tree in the foreground of the eruption-image is an Ohi’a lehua (Metrosideros polymorpha). As of this writing, the species, endemic to Hawaii, is suffering from ROD (Rapid Ohia Death) from invasive fungi. Ohi’a is one of the first species to appear on “new” lava – once it has cooled.

Videos and text here: “Kīlauea was erupting at the summit most recently from September 10-16, 2023. Several roughly east-west oriented vents on the western side of the downdropped block within Kīlauea’s summit caldera generated lava flows onto Halema‘uma‘u crater floor, within Hawai‘i Volcanoes National Park. ”

Halemaʻumaʻu is home to Pele, goddess of fire and volcanoes, according to the traditions of Hawaiian religion. Halemaʻumaʻu means ‘house of the ʻāmaʻu fern’.”

Kilauea after the eruption stopped:

Three videos of the 2023 Kilauea eruption:

A  Wild Hawaiian Orchid.

” Their technical names are Anoetochilus sandvicensis (the jewel orchid); Liparis hawaiensis (the twayblade orchid); and Platanthera holochila. These native orchids grow in the very highest places within the island’s forests and bog.” 

Orchids for my mother on the blue slate of the Pacific.

The Golden Pools of Keawaiki:

From this site:

“The Golden Pools of Keawaiki on the Kohala coast are landlocked freshwater ponds (anchialine pools) connected to the ocean. Lava fields surround them, and the only greenery is saplings growing at these oases. The Golden Pools of Keawaiki got their name from the gold-colored algae growing on the underwater rocks.”

Mauna Kea, the White Mountain, so named for the snow along its flanks during the colder months of the year. Mauna Kea is ~13,800 feet high.

Quote:If we measure the entire mountain from top to its base, which is referred to as the ‘dry prominence’, Mauna Kea is 500 metres (1640 feet) taller than Everest.”

The observatory-domes of several world class telescopes are located atop the mountain; the W.M Keck Telescope, the Gemini, the Subaru, the CFHT (Canada France Hawaii Telescope), and the NASA infrared Telescope Facility are among the ~13 scopes on the White Mountain. I worked for both the CFHT and Keck Telescopes prior to switching career paths. The Thirty Meter Telescope (the TMT) was slated for completion prior to 2019, but was successfully halted after several years of protest by native Hawaiian groups. Hawaiian mythology considers the mountain “sacred”. In a tragedy for science, the compromise, if one is reached, may prove fatal for the future of astronomy on Mauna Kea, the world’s best site for ground-based astronomy.

Quote: “The height of the mountain, lack of light pollution, dry atmosphere, and minimal air disturbances make Maunakea the foremost place in the world for astronomy research.”

Quote: “Crucially, the MKSOA includes representatives from both astronomical observatories and Native Hawaiian communities. Its members say it marks a new approach, one that for the first time gives Native Hawaiians a voting role in overseeing the mountaintop. And although board members don’t want to get ahead of the process, an emerging compromise could see the embattled TMT built atop the peak in exchange for the decommissioning of several telescopes.”

Ironically, Hawaii’s coastline is also “sacred’ to Hawaiians, however, no clarion call has been issued to decommission the multiple hotels along the coastline. Connect the dots. Commerce and skill sets.

Mauna Loa, the Long Mountain, slightly less in height than Mauna Kea. Hawaii Volcano’s National Park lies to the south of Mauna Loa.

Categories: Science

Paper planes made by a robot fly better than ones made by humans

New Scientist Feed - Tue, 03/26/2024 - 5:00am
A robot that can design, build and test objects made from folded paper can make paper planes that fly further than ones made by a human having the same number of attempts
Categories: Science

Ancient people carved mysterious symbols near dinosaur footprints

New Scientist Feed - Tue, 03/26/2024 - 3:28am
A unique site in Brazil features rock carvings closely associated with dinosaur tracks, suggesting prehistoric people saw the footprints as meaningful
Categories: Science

Huge crater in India hints at major meteorite impact 4000 years ago

New Scientist Feed - Tue, 03/26/2024 - 1:00am
The Luna structure, a 1.8-kilometre-wide depression in north-west India, may have been caused by the largest meteorite to strike Earth in the past 50,000 years
Categories: Science

Your nationality may influence how much you talk with your hands

New Scientist Feed - Mon, 03/25/2024 - 10:00pm
When recounting an episode of the children's TV show Pingu, people from Italy made an average of 22 gestures per 100 words, compared with 11 for Swedish people
Categories: Science

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