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Keto diet helps with weight loss but also raises cholesterol levels

New Scientist Feed - Mon, 08/05/2024 - 10:00am
A low-carbohydrate ketogenic diet is linked to greater fat loss than a low-sugar diet, but also higher cholesterol levels
Categories: Science

Astronomers See Planets Forming Around Binary Stars

Universe Today Feed - Mon, 08/05/2024 - 9:58am

Over 5,000 exoplanets have been discovered around distant star systems. Protoplanetary disks have been discovered too and it’s these, out of which all planetary systems form. Such disks have recently been found in two binary star systems. The stellar components in one have a separation of 14 astronomical units (the average distance between the Earth and Sun is one astronomical unit) and the other system has a separation of 22 astronomical units. Studying systems like these allow us to see how the stars of a binary system interact and how they can distort protoplanetary disks.

The discovery of planetary systems around other stars has changed our view of the universe and how stellar systems evolve. The first confirmed detection occurred in 1995 and since then, advanced telescopes and detection techniques have enabled the detection of thousands of exoplanets. Space missions like Kepler and TESS have helped to categorise the planets and have identified large gas planets to Earth-sized rocky worlds, some in their star’s habitable zone. Protoplanetary disks have also been studied and so our understanding of the formation of planetary systems has improved markedly since. 

Artist’s impression of a young star surrounded by a protoplanetary disc made of gas and dust. According to new research, ring-shaped, turbulent disturbances (substructures) in the disk lead to the rapid formation of several gas and ice giants. Credit: LMU / Thomas Zankl, crushed eyes media

The disks of gas and dust around stars have been known to be the precursor to planetary systems for some years. What has been uncertain is the conditions that allow the disk to remain long enough for planets to form and what can lead to their early dissipation. 

An announcement of protoplanetary disks around young binary stars was announced at a meeting of the American Astronomical Society by a team of researchers from National Radio Observatory. They used the Atacama Large Millimetre/sub-millimetre Array otherwise known as ALMA and the near-infrared capability of the Keck II 10 metre telescope. ALMA has been setup in the Atacama Desert at an altitude of 5,000 metres so that the air is clear and dry. It’s composed of 66 antennae all working together as an interferometer to study the coldest and most distant objects in the universe.

Two of the Atacama Large Millimeter/submillimeter Array (ALMA) 12-metre antennas (Credit : Iztok Bon?ina/ESO)

The disks around pre-main sequence binary stars as announced provides an excellent opportunity to study the disks and try to find answers to the questions. The team explored the disk sizes, structure and inclination in relation to the star’s rotation speed and magnetic field strength to try and understand the complex processes at play. Binary and multiple star systems like the DF Tau and FO Tau binary system that were the target of the study are common making an excellent case study. 

DF Tau is a binary quasi-twin star system with component separation of 14 astronomical units with elongated orbits. ALMA detected two circumstellar cool dust disks with one locked magnetically to the star and accreting material onto it. The inner disk seems to have largely eroded and decoupled from the rapidly rotating star. This suggests a link between the rotation of the star, magnetic disk locking and the resultant early disk dissipation. Misalignment of the orbits and disks could impact the evolution of the disk. FO Tau is slightly different where the disks are aligned with the binary orbit, the stars have modest rotation speeds and seem to be magnetically locked to their disks.

ALMA has afforded high resolution images revealing fine levels of disk sub-structures which include spiral patterns, gaps and ring formations around single stars and wide binary companions. It cannot yet resolve detail in the disks of DF Tau and FO Tau systems, to be able to determine disk properties in close binary systems marks a step forward in our understanding of planetary formation.

Source : ALMA Observations Reveal New Insights into Planet Formation in Binary Star Systems

The post Astronomers See Planets Forming Around Binary Stars appeared first on Universe Today.

Categories: Science

How clues in honey can help fight our biggest biodiversity challenges

New Scientist Feed - Mon, 08/05/2024 - 9:00am
There are secrets aplenty in a pot of honey – from information about bees' "micro-bee-ota" to DNA from the environment – that can help us fight food fraud and even monitor shifts in climate
Categories: Science

Robo-tuna reveals how foldable fins help the speedy fish manoeuvre

New Scientist Feed - Mon, 08/05/2024 - 8:47am
A robot mimics the clever fin-folding mechanism used by tuna fish, which increased the bot's turning velocity by almost 33 per cent
Categories: Science

Banana-shaped galaxies are helping unpeel the mysteries of dark matter

New Scientist Feed - Mon, 08/05/2024 - 8:00am
Astronomers have been spotting strange banana-shaped galaxies and the evidence seems to indicate that filaments of dark matter make them take this shape
Categories: Science

How conspiracy theories like COVID-19 “lab leak” harm science and public health

Science-based Medicine Feed - Mon, 08/05/2024 - 12:00am

Ever since COVID-19 first emerged in 2020, evidence-free claims that it had arisen due to a "lab leak" have proliferated. A recent paper argues that this conspiracy theory has been very harmful to science. I argue that it's more than just lab leak that is harmful.

The post How conspiracy theories like COVID-19 “lab leak” harm science and public health first appeared on Science-Based Medicine.
Categories: Science

Streetlights may make tree leaves tough and hard for insects to eat

New Scientist Feed - Sun, 08/04/2024 - 10:00pm
Trees in Beijing lit by streetlights at night seem to have tougher leaves and less damage from insects, raising concerns about possible effects on biodiversity
Categories: Science

This just in: “Cats Are Better Than Dogs”

Why Evolution is True Feed - Sun, 08/04/2024 - 11:53am

by Greg Mayer

In Jerry’s absence, I’m relaying an item from the New York Times that he may not see right away:

I early noted Pamela Paul’s perspicacity, and Jerry has taken note of her views a number of times. It’s in the paper of record, so it must be true!

Money quote:

Only in truly knowing and accepting one another, do we achieve deep love.

Yes, what I’m saying is that cats are more like people. As with humans, so with cats, who can be adored but not mastered; responsive, but never controlled; truly loved only with mutual acceptance and respect. And why expect more from our animals than we would wish for ourselves?

Categories: Science

Greg Eghigian — UFO Sightings Around the World: A Comprehensive History

Skeptic.com feed - Sat, 08/03/2024 - 12:00pm
https://traffic.libsyn.com/secure/sciencesalon/mss453_Greg_Eghigian_2024_08_03.mp3 Download MP3

Roswell, 1947. Washington, DC, 1952. Quarouble, 1954. New Hampshire, 1961. Pascagoula, 1973. Petrozavodsk, 1977. Copley Woods, 1983.

Explore how sightings of UFOs and aliens seized the world’s attention and discover what the fascination with flying saucers and extraterrestrial visitors says about our changing views on science, technology, and the paranormal.

In the summer of 1947, a private pilot flying over the state of Washington saw what he described as several pie pan-shaped aircraft traveling in formation at remarkably high speed. Within days, journalists began referring to the objects as “flying saucers.” Over the course of that summer, Americans reported seeing them in the skies overhead. News quickly spread, and within a few years, flying saucers were being spotted across the world. The question on everyone’s mind was, what were they? Some new super weapon in the Cold War? Strange weather patterns? Optical illusions? Or perhaps it was all a case of mass hysteria? Some, however, concluded they could only be one thing: spacecrafts built and piloted by extraterrestrials. The age of the unidentified flying object, the UFO, had arrived.

Greg Eghigian tells the story of the world’s fascination with UFOs and the prospect that they were the work of visitors from outer space. While accounts of great wonders in the sky date back to antiquity, reports of UFOs took place against the unique backdrop of the Cold War and space age, giving rise to disputed government inquiries, breathtaking news stories, and single-minded sleuths. After the Flying Saucers Came traces how a seemingly isolated incident sparked an international drama involving shady figures, questionable evidence, suspicions of conspiracy, hoaxes, new religions, scandals, unsettling alien encounters, debunkers, and celebrities. It examines how descriptions, theories, and debates about unidentified flying objects and alien abduction changed over time and how they appeared in the United States, Europe, Latin America, Asia, and Russia. And it explores the impact UFOs have had on our understanding of space, science, technology, and ourselves up through the present day.

Replete with stories of the people who have made up the ufology community, the military and defense units that investigate them, the scientists and psychologists who have researched these unexplained encounters, and the many novels, movies, TV shows, and websites that have explored these phenomena, After the Flying Saucers Came speaks to believers and skeptics alike.

Greg Eghigian is a Professor of History and Bioethics at Pennsylvania State University. An expert on the history of the abnormal and the paranormal in the modern world, his research has been supported by NASA and the Smithsonian National Air and Space Museum. He is the author of The Corrigible and the Incorrigible: Science, Medicine, and the Convict in Twentieth Century Germany and the editor of The Routledge History of Madness and Mental Health, among other works. His new book is After the Flying Saucers Came: A Global History of the UFO Phenomenon.

Shermer and Eghigian discuss:

  • Separating two questions: Are they out there? Have they come here?
  • SETI science vs. UFO/UAP science
  • Will aliens look anything like us? Convergent vs. contingent evolution
  • What alien intelligence might be like: biological, digital, or otherwise?
  • Bayesian reasoning about UFOs and UAPs
  • The U.S. military UAP videos and what they represent
  • The Disclosure Project from the U.S. government about UFOs and UAPs
  • Projects Sign, Blue Book, Cyclops, Grudge
  • AATIP (Advanced Aerospace Threat Identification Program)
  • UFOs as mythology and myth making
  • UFO waves and flaps in history and what explains them
  • The UFO movement and what drives it
  • Government interests in UFO
  • NAZI UFOs, CIA UFOs, etc.
  • Why aliens matter.

If you enjoy the podcast, please show your support by making a $5 or $10 monthly donation.

Categories: Critical Thinking, Skeptic

A note about politics

Why Evolution is True Feed - Sat, 08/03/2024 - 10:00am

Here’s what I won’t miss about politics:

Trump and now Vance are repeatedly shooting themselves in the foot by making stupid statements.  Any idiot would know that saying that Kamala Harris turned black from Asian would not please most voters, including Republicans. I’m not sure whether Harris once emphasized her Asian ancestry and then her black ancestry at a later time, but even calling attention to that is invidious.  Like many voters, including black ones, I do not want this election to be about race; I want it to be about issues.

Vance, who was chosen for his hardscrabble background designed to appeal to middle America, has proved to be somewhat of a drag on the ticket. His comment on childless cat ladies was just as bad as Trump’s gaffe, and he topped that by criticizing Simone Biles for pulling out of the last Olympics because of mental health issues. That’s just churlish. None of these statements have anything to do with issues; they are ad hominems.

Harris, on the other hand, accepted her coronation with glee, and I’m appalled that people with much better cred, including Obama and Pelosi, jumped aboard the Harris juggernaut so quickly. I am not enthused about her stand on Israel, on her wokeness (she’s increasingly “progressive”, and will do damage to Titles VI and IX) and her weakness on the border, though she’s keeping a low profile right now.  What irks me the most is her claim that she wasn’t going to simply inherit the Democratic nomination, but EARN it. Well, she’s done absolutely nothing to earn it except serve up a few more word salads (I swear, she is incapable of thinking on her feet, and becomes acceptable only when reading from a teleprompter).

This is one election when I’m not enthused about either candidate. I remain a Democrat and a huge critic of Trump, whom I consider mentally ill, but I can’t say that I wouldn’t be holding my nose when voting for Harris. I am appalled at what’s happened to the Democratic Party. Yes, they are dancing with glee around a mediocre candidate, for they want to win, but what happened to the search for quality?  Perhaps it was too late to have debates or resolve this in the Democratic Convention, for it’s already been solved. Still . . . .

But the laws of physics have already determined who will win the Presidency, so I suppose I should just relax and let the molecules work it all out.

Categories: Science

Seal webcam!

Why Evolution is True Feed - Sat, 08/03/2024 - 8:00am

Reader Patricia kindly left us with something to look at while I’m gone: the webcam of seals and other wildlife living on Año Nuevo Island off the coast of California. As you can read below, Patricia works here.

Here is the location from Wikipedia:

Patricia gives us the lowdown (indented), and the link to the webcam is below.

Año Nuevo Island is a small island (~9 acres) off the central coast of California, ~60 mi. south of San Francisco .  The webcam is supported by California State Park.  The camera shows the SE end of the island in 3 views, each about 30 sec. View #1 is a sandy beach that extends toward the mainland with a collapsing catwalk across the center of the scene.  In winter hundreds of Northern elephant seals (Mirounga angustirostris) pup and mate here.  Currently (Aug.) the beach is used by thousands of California sea lions (Zalophus californianus) and a few molting male e-seals.  Sea lions sometimes sleep atop these king size ’Sealy Posturpedics’.  If there is a point break, the sea lions enjoy surfing it.  In the foreground there are some of the thousands of nesting Brandt’s cormorants (Urile penicillatus).  The chicks are almost full grown now, but still ‘fuzzy’ View #2 shows the top terrace of the island and the deteriorating light keeper’s house (built 1906, fog horn station began in 1872 – replaced by a buoy in 1948).  The terrace and house are occupied by thousands of sea lions and cormorants. A few Western gulls (Larus occidentalis) attempt to nest amidst the fray.  Fog allowing, the ridge on the mainland shows a very ragged tree line, the result of the 2020 CZU lightning complex fire.  It was dense forest pre-fire. View #3 is a rocky cove on the ocean side of the island occupied by hundreds of sea lions and their pups can often be seen playing here.  Brown pelicans (Pelecanus occidentalis) can sometimes be seen roosting below the camera. On a warm day, if you check the camera at midday and then again in the early evening, you can see a mass migration of the sea lions from down on the cooler, wetter beaches up to the dryer terrace. I’ve been working at Año Nuevo for 30+ years including about a dozen when I spent a good part of the summer on the island.  It is often chilly and very windy there, necessitating watch cap plus hard hat (for gull strikes of both feet and guano, they have incredible aim and adjust for the wind), gloves, five layers on my torso and knee pads since most movement was on hands and knees.  If you have questions, ask in the comments and I’ll try to answer them.

Click on the screenshot and bookmark it for hours of fun and enlightenment. If your browser doesn’t work (I have trouble on Chrome), try another. The link is also here.

From the webcam’s site:

The Año Nuevo Island camera provides viewers with spectacular views of Año Nuevo Island live. Several angles are displayed for 30 seconds before the camera pans to the next position. The camera is live from 8:00 am – 5:00 pm.

Located 1/2 mile from the mainland, Año Nuevo Island is not accessible for the general public. It has been set aside with other sections of Año Nuevo State Park as a Natural Preserve, dedicated as habitat for a diversity of wildlife. Although now a home for marine mammals and nesting birds, evidence of human occupation is still evident from the historic light station buildings that began operation in 1872. These buildings were abandoned in 1948 and some still stand today.

Categories: Science

The Skeptics Guide #995 - Aug 3 2024

Skeptics Guide to the Universe Feed - Sat, 08/03/2024 - 8:00am
OIympic Controversy; News Items: Progeria Treatment, Solid State Battery, The Cass Review, Mammoth DNA; Who's That Noisy; Your Questions and E-mails: The Bacterial Flagellum; Science or Fiction
Categories: Skeptic

I have almost departed

Why Evolution is True Feed - Sat, 08/03/2024 - 7:00am

I arose a the ungodly hour of 3:45 a.m. showered, dressed, checked my luggage, and then took an Uber to O’Hare. Traffic was sparse and I got here 2.5 hours early, so here’s the post.

Notable events: I have to take malaria medication, and my doctor said I should take one pill a day (they’re big and bitter) starting three days before I arrive and continuing for a week thereafter. Believe me, you don’t want to get malaria! I have also taken my requisite four typhoid pills, got a preventive Covid shot and the first two doses of the Hepatitis B vaccine (the last dose will be three months after I return). I also have iodine pills to disinfect water. I don’t want to get sick on my Big Trip to See Animals.

I’ll be in Capetown for about eight days staying with old friends Martim and Rita (both biologists) who have a lovely cottage overlooking the ocean.  During this time we’ll have a four-day field trip in the area, but I’m not quite sure of all the details.

Besides that, my plans include the usual tourist sites: visiting Robben Island to see the cell where Nelson Mandela spent 27 years of his life, visiting the Cape Penguins (Spheniscus demersus) to add another penguin to my life list (there are about six on it now), going atop Table Mountain, and seeing the unusual flora in the fynbos region (one of only a few floral regions in the world, and the smallest one), described this way:

One of only six floral kingdoms in the world and unique to this small area, the region supports over 9,000 plant species, 70% of which are found nowhere else on the planet. These include exquisite species such as the king protea (South Africa’s national flower) and exotic pincushions.

Here’s a king protea (Protea cynaroides):

Stan Shebs, CC BY-SA 3.0 via Wikimedia Commons

After Capetown I fly north for the Animal Expedition. Thanks for my friend Rosemary, I have booked my own stay in a game lodge (yes, a fancy one) for a few days, which provides two animal-viewing trips per day as well as bushwalks on foot.  Then it’s on to a two-day river trip (I’m not quite sure of the details, but it’s supposed to be lovely), and then three of us will drive through Kruger Park, again looking for animals and staying in basic accommodations.

Seeing the “Big Five” animals is the goal of all travelers; they are the lion, the Cape Buffalo, the leopard, the rhino, and of course the elephant. Of these, the secretive leopard is the hardest to see, but lions and elephants are normally on tap.

I will also see the Common Warthog, which really should be one of the Big Five. At last I’ll be able to see Ozy, who is still dominating the area and eating well.

Finally, a friend of Martim who studies the Great Hornbill (Buceros bicornis), a corker of a bird, promised to show them to us toward the end of the month. Here’s a video of this remarkable species:

After all this I’ll return to Capetown for a day or two, and then back to America, where, thank Ceiling Cat, I’ll have missed all the crazy politics that will ensue for a month.

The next trip after that is the CSICon meetings in Las Vegas in October, where I’ll be giving a talk and then heading to southern Utah to visit a friend. In December I go to Poland to give two invited talks at a popular-science meeting in Silesia, and of course to visit my friends Malgorzata, Andrzej, Hili, Kulka, and Szaron in Dobrzyn.  After that, a trip to New York for a Heterodox Academy panel, and, in July of 2025, a trip to the Arctic—another goal on the bucket list.

So it goes. I am glad to be free of the craziness that is American politics for a while and relax in nature.  I will post as I can, but if the internet is rare, or I don’t have time, rest assured that there will be animal photos when I return. As always, I do my best.

Categories: Science

Saturday: Hili dialogue

Why Evolution is True Feed - Sat, 08/03/2024 - 1:25am

While PCC(E) is travelling, I will be posting Hili every day, with occasional additions as the mood (and time) takes me. Jerry will post when he can. For today, however, it’s “just” Hili! –  Matthew

Meanwhile in Dobrzyn, Szaron and Hili are on the track of a talpinid…

Szaron: I can barely wait. Hili: What for? Szaron: When this mole will come to the surface. In Polish: Szaron: Nie mogę się doczekać.
Hili: Na co?
Szaron: Kiedy ten kret wyjrzy na powierzchnię.
Categories: Science

Are horses in equestrian sports being harmed by bending their necks?

New Scientist Feed - Fri, 08/02/2024 - 3:24pm
Horses experience hyperflexion when their necks bend far towards their chests – forcing this position can hurt a horse but when it happens naturally it can be harmless
Categories: Science

A blueprint for building the future: Eco-friendly 3D concrete printing

Matter and energy from Science Daily Feed - Fri, 08/02/2024 - 2:09pm
Scientists are improving 3D concrete printing construction technology with rigorous research to make printable materials stronger, more sustainable and better performing.
Categories: Science

China's Lunar Samples Contain Graphene Flakes

Universe Today Feed - Fri, 08/02/2024 - 2:04pm

In 2004, scientists at the University of Manchester first isolated and investigated graphene, the supermaterial composed of single-layer carbon atoms arranged in a hexagonal honeycomb lattice. Since then, it has become a wonder, with properties that make it extremely useful in numerous applications. Among scientists, it is generally believed that about 1.9% of carbon in the interstellar medium (ISM) exists in the form of graphene, with its shape and structure determined by the process of its formation.

As it happens, there could be lots of this supermaterial on the surface of the Moon. In a recent study, researchers from the Chinese Academy of Science (CAS) revealed naturally formed graphene arranged in a special thin-layered structure on the Moon. These findings could have drastic implications for our understanding of how the Moon formed and lead to new methods for the manufacture of graphene, with applications ranging from electronics, power storage, construction, and supermaterials. They could also prove useful for future missions that will create permanent infrastructure on the lunar surface.

The team was led by professors Wei Zhang and Meng Zou from the Key Laboratory of Bionic Engineering and the Jilin Provincial International Cooperation Key Laboratory of High-Efficiency Clean Energy Materials at Jilin University, Jilin University senior engineer Xiujuan Li, and Wencai Ren from the CAS’ Institute of Metal Research (CAS-ISM). They were joined by colleagues from multiple Key Laboratories at Jilin University, the CAS-ISM, the Deep Space Exploration Lab, and the Lunar Exploration and Space Engineering Center. The paper that describes their findings appeared in the National Science Review.

For decades, scientists have speculated that the Earth-Moon system was formed from a massive collision – the Giant Impact Hypothesis – between a Mars-sized body (Theia) and Earth roughly 4.4 billion years ago. This theory is supported by analyses of the moon rocks returned by the Apollo astronauts, which led to the notion of a carbon-depleted. However, recent findings have come to challenge this consensus based on the observation of global carbon ion fluxes on the Moon, which suggest the presence of indigenous carbon.

These observations are consistent with the analysis of one of the Apollo 17 samples that showed the presence of graphite. For their study, the team conducted a spectroscopic analysis of an olive-shaped sample of lunar soil (measuring about 2.9 mm by 1.6 mm) retrieved by the Chang’e 5 mission in 2020. This was China’s third robotic mission to reach the lunar surface and its first sample return from the Moon. From the spectra they obtained, they found an iron compound in a carbon-rich section of the sample that is closely related to the formation of graphene.

Upon further analysis using advanced microscopic and mapping technologies, they confirmed that the carbon in the sample was graphene flakes two to seven layers thick. In terms of how it got there, the team proposed that the graphene may have formed during a period of volcanic activity early in the Moon’s history when it was still geologically active. They further hypothesize that the graphene was catalyzed by solar winds that kicked up the lunar regolith and its iron-containing minerals, which could have helped transform the carbon’s atomic structure.

They also allow for the possibility of meteorite impacts, which are also known to create high-temperature and high-pressure environments similar to volcanic activity. As they state in their paper:

“Graphene is embedded as individual flakes or formed as part of a carbon shell enclosing the mineral particles. Our result reveals one typical structure of indigenous carbon in the Moon and its formation mechanism has been proposed. This finding may reinvent the understanding of chemical components, geography episodes and the history of the Moon.”

Artist’s impression of the interior of the Moon. Credit: Hernán Cañellas/Benjamin Weiss

These findings could also have a tremendous impact on research here on Earth, where graphene is being investigated for applications ranging from electronics and mechanics to materials science. As they indicate in their study, this study could lead to new methods for inexpensively producing the material and offer additional opportunities for lunar exploration:

“The identification of graphene in the core–shell structure suggests a bottom-up synthesis process rather than exfoliation, which generally involves a high-temperature catalytic reaction. Therefore, a formation mechanism of few-layer graphene and graphitic carbon is proposed here…

“In turn, the mineral-catalysed formation of natural graphene sheds light on the development of low-cost scalable synthesis techniques for high-quality graphene. Therefore, a new lunar exploration program may be promoted and some forthcoming breakthroughs can be expected.”

These findings could also prove useful for future missions that will lead to the development of permanent infrastructure on the lunar surface. This includes NASA’s Artemis Program, which aims to create a “sustained program of lunar exploration and development.” There’s also the ESA’s Moon Village initiative and China and Russia’s plan for an International Lunar Research Station (ILRS). In addition to exploration and scientific research, these programs could conduct experiments on the properties and uses of graphene, which could include the manufacture of lunar habitats!

Further Reading: EurekAlert!, National Science Review

The post China's Lunar Samples Contain Graphene Flakes appeared first on Universe Today.

Categories: Science

Bacteria originally found in faeces help chronic wounds heal

New Scientist Feed - Fri, 08/02/2024 - 2:00pm
The bacterium Alcaligenes faecalis was first discovered in faeces – but it turns out to have healing properties for the chronic wounds that affect people with diabetes
Categories: Science

The Surface of Dimorphos is Surprisingly New

Universe Today Feed - Fri, 08/02/2024 - 1:05pm

When NASA’s DART mission intentionally slammed into Dimorphos in September 2022, the orbit of the moonlet was altered. Researchers have studied the photos and data taken by DART before its impact, learning more about the geology of the Didymos/Dimorphos system. They have now estimated the surface age of both the asteroid and its moon. The asteroid Didymos has a surface age of 12.5 million years, while the moon Dimorphos is only 300,000 years old.

Additionally, the DART researchers concluded both Didymos and Dimorphos are rubble piles, with Dimorphos likely inheriting its boulders from Didymos.

“It’s a pile of gravel and boulders (and some sand/dust) held together by its own gravity, and really not anything else,” said Andy Rivkin, DART investigation team co-lead at the Johns Hopkins Applied Physics Lab (APL), on Bluesky. “There’s really no cohesion between different pieces of gravel or rocks on Dimorphos.”

That makeup explains why DART’s impact made such a such a surprising change in Dimorphos’ orbital period, decreasing it by about 34 minutes. A collection of boulders is easier to shift than a solid object.

Several DART researchers published five papers in Nature Communications, looking at the geology and geophysics of Didymos and Dimorphos as seen by DART.

“These findings give us new insights into the ways that asteroids can change over time,” said Thomas Statler, lead scientist for Solar System Small Bodies at NASA Headquarters in Washington, in a NASA press release. “This is important not just for understanding the near-Earth objects that are the focus of planetary defense, but also for our ability to read the history of our Solar System from these remnants of planet formation. This is just part of the wealth of new knowledge we’ve gained from DART.”

In “The geology and evolution of the Near-Earth binary asteroid system (65803) Didymos,” Olivier Barnouin, Ronald-Louis Ballouz, also of APL, and their team were able to determine the disparate ages of Didymos and Dimorphos. They also found that both objects have weak surface characteristics, which very likely contributed to DART’s significant impact on the moonlet’s orbit.

“The images and data that DART collected at the Didymos system provided a unique opportunity for a close-up geological look at a near-Earth asteroid binary system,” said Barnouin, in a press release from APL. “From these images alone, we were able to infer a great deal of information on geophysical properties of both Didymos and Dimorphos, and expand our understanding of the formation of these two asteroids. We also better understand why DART was so effective in moving Dimorphos.”

In five new Nature Communications papers, the team behind @NASA's successful #DARTMission sheds new light on the structure and origins of the asteroid system encountered in 2022. https://t.co/G7x5tQyriq@NASASolarSystem @AsteroidWatch pic.twitter.com/i82oxbrXxw

— Johns Hopkins APL (@JHUAPL) July 30, 2024 Based on the internal and surface properties described in Barnouin et al. (2024), this video demonstrates how the spin-up of asteroid Didymos could have led to the growth of its equatorial ridge and the formation of the smaller asteroid Dimorphos, seen orbiting the former near the end of the clip. Particles are colored according to their speeds, with the scale shown at the top, along with the continually changing spin period of Didymos. Credit: University of Michigan/Yun Zhang and Johns Hopkins APL/Olivier Barnouin

Images captured by DART and its cubesat companion the LICIACube – contributed by the Italian Space Agency (ASI)  — showed Dimorphos’ topography covered with boulders of varying sizes, while the larger asteroid Didymos was smoother at lower elevations, though rocky at higher elevations. It also had more craters than Dimorphos. The authors inferred that Dimorphos likely spun off from Didymos in a large mass shedding event.

This was confirmed in another paper, “Evidence for multi-fragmentation and mass shedding of boulders on rubble-pile binary asteroid system (65803) Didymos.” Maurizio Pajola, of the National Institute for Astrophysics (INAF) in Rome, and team show how both Didymos and Dimorphos are mainly comprised of a collection of boulders. This team concluded that the formation of Dimorphos likely came as Didymos shed material, creating a new asteroid moonlet.

“The size-frequency distribution of boulders larger than 5 meters on Dimorphos and larger than 22.8 meters on Didymos confirms that both asteroids are piles of fragments produced in the catastrophic disruption of their progenitors,” the team wrote. “This finding supports the hypothesis that some asteroid binary systems form through the spin up and mass shedding of a fraction of the primary asteroid.”

In another paper, “Fast boulder fracturing by thermal fatigue detected on stony asteroids” Alice Lucchetti, also of INAF, and colleagues found that the size and distribution of boulders on Dimorphos is consistant with thermal fatigue, which is the gradual weakening and cracking of a material caused by heat. This could rapidly break up boulders on the surface of Dimorphos, generating surface lines and altering the physical characteristics of this type of asteroid more quickly than previously thought. The DART mission was likely the first observation of such a phenomenon on this type of asteroid.

Thermal fatigue could also have a bearing on what happens if this type of asteroid would need to be deflected for planetary defense.

“The presence of boulder fields affected by thermal fracturing on near-Earth asteroid surfaces may contribute to an enhancement in the ejected mass and momentum from kinetic impactors when deflecting asteroids,” the authors wrote.

a. The approximate equator (dashed magenta line), example boulder tracks (magenta arrows) and likely boulders (white arrows) on the surface of Didymos. b. The 15 boulder tracks identified on the surface of Didymos are indicated by the magenta lines. Credit: Bigot, Lombardo et al.

Another paper, “The bearing capacity of asteroid (65803) Didymos estimated from boulder tracks” led by students Jeanne Bigot and Pauline Lombardo of ISAE-SUPAERO in Toulouse, France show that the bearing capacity — the surface’s ability to support applied loads of asteroid Didymos’ surface is only 0.1% that of dry sand on Earth. NASA said that this is considered an important parameter for understanding and predicting the response of a surface, including for the purposes of displacing an asteroid.

Finally, “Mechanical properties of rubble pile asteroids through surface boulder morphological analysis” by Colas Robin, also of ISAE-SUPAERO, and co-authors analyzed the surface boulders on Dimorphos, comparing them with those on other rubble pile asteroids, including Itokawa, Ryugu and Bennu. The researchers found “stiking similarities” the boulders on all four asteroids, suggesting they all formed and evolved in a similar fashion, and were also changed by impacts. This data, too, informs future planetary defense missions or attempts at impactor missions.

“Planetary defense efforts rely on estimates of the mechanical properties of asteroids, which are difficult to constrain accurately from Earth,” the team wrote. “The mechanical properties of asteroid material are also important in the interpretation of the DART impact.”  

All the DART researchers team will continue to observe and study DART’s impact. Additionally, another spacecraft will launch in 2024 to study Dimorphos even closer. ESA’s Hera mission should arrive at Didymos and Dimorphos in December 2026. Hera will undertake a detailed study of Dimorphos to understand more deeply how the impact affected it.

The post The Surface of Dimorphos is Surprisingly New appeared first on Universe Today.

Categories: Science

A Tower On The Moon Could Provide Astronauts With Light, Power, and Guidance

Universe Today Feed - Fri, 08/02/2024 - 12:41pm

Technologies for enabling NASA’s Artemis mission are coming thick and fast, as plenty of problems must be solved before a permanent human presence on the Moon can be established. A novel idea from Honeybee Robotics, one of the most prominent space technology companies now owned by Blue Origin, could solve plenty of them with one piece of infrastructure. The Lunar Utility Navigation with Advanced Remote Sensing and Autonomous Beaming for Energy Redistribution, or LUNARSABER (which must have been named by someone who really likes Star Wars), is a 100m tall pole that can hold one ton of equipment on top of it. It could serve as a central power, communications, and lighting hub of an Artemis base and part of a mesh network with other places of interest on the Lunar surface. 

Let’s start with the enabling tech of LUNARSABER itself. No rocket can hold a 100-meter-tall tower and land it on the Moon, and building such a tower on the lunar surface without any existing infrastructure would also be almost impossible. So Honeybee will leverage another existing technology—the Deployable Interlocking Actuated Bands for Linear Operations, or DIABLO system (maybe someone at Honeybee also likes Blizzard Entertainment games).

DIABLO uses a rolled piece of metal and bends it into a deployable cylindrical structure that supports heavy payloads. In this case, that structure serves as the base for LUNARSABER. But the secret sauce is what that structure enables. Let’s take a look at what goes along the sides first.

This video from Honeybee describes the LUNARSABER project in detail.
Credit – Honeybee Robotics YouTube Channel

Since power is such an important thing on the Moon, it seems evident that putting solar panels along the sides is the most useful, and that is precisely what Honeybee is doing. In a recently released video, they discuss two types of solar panel deployments. One looks like a yo-yo extended from the top payload holder of the LUNARSABER tower. This methodology would entirely envelop the metallic structure underneath but allow access to the Sun at all angles. Alternatively, the top part of the 100m tower could deploy its booms that hold traditional solar panels and then track where the Sun is as it makes its 14-day journey across the lunar sky.

Honeybee’s engineers estimate it could produce about 100kW of power using these techniques, but it also has some other advantages. Some parts of the lunar poles are bathed in eternal sunlight – or are very close to being so. At these places, a tall pole would capture at least some sunlight almost 95% of the time. Admittedly, the sunlight would only hit the top part of LUNARSABER, significantly decreasing its overall power output. However, having some power during the cold lunar night is undoubtedly better than not having any and relying on batteries for survival.

Supplying power is only one part of what LUNARSABER does, though. It has four main other capabilities:

  1. It can beam power to other devices
  2. It can track those other devices
  3. It can communicate with a wide range of assets
  4. It can provide light for those assets.
Fraser discusses how power beaming works with Dr. Stephen Sweeney.

Let’s tackle the first one first. Power beaming is all the rage in the space technology community, partly due to recent successful tests by Caltech and the US’s Naval Research Laboratory. This technology could be applied to LUNARSABER as well. If one mast is bathed in sunlight while another lingers in shadow, the one with excess power can beam power to the one needing it. Additionally, that power beaming can occur between the LUNARSABER and individual assets such as rovers or astronauts in spacesuits. If one needs a power fill-up, a 100m tower with a power beaming system on top of it could provide that fill-up over a vast area very effectively.

Beaming power effectively to those assets requires the LUNARSABER to know where they are, though. That’s where the second enabling technology comes in. It can use a series of sensors to find and track different assets as they operate around the LUNARSABER tower. Anything with a direct line of sight could be tracked and powered directly by the tower itself. 

Line of sight is also helpful for the subsequent use case but unnecessary. LUNARSABER could serve as a kind of lunar cell phone tower, enabling wireless communication between the assets in its network. This prototype internet allows different rovers to coordinate together or an astronaut in one part of the base to issue a command to a rover in a different part.

Fraser discusses the importance of having capabilities and infrastructure set up properly for exploration.

Finally, to issue those commands, it would be helpful for astronauts to see where they’re going. It’d also be helpful for rovers, as many of their science missions would otherwise have to wait out the two-week lunar darkness. Floodlights on the top of LUNARSABER could provide visible light to these astronauts and rovers, allowing them to effectively perform their activities whether it’s lunar night or not.

Another aspect of LUNARSABER that utilizes a few of the different applications mentioned above is combining several towers in a line-of-sight mesh, which would allow both communication and power to be beamed from literally the other side of the Moon. This enables two main applications that have proven a thorn in Lunar Exploration’s side: constant solar power and constant communication with Earth.

Since at least half of the Moon is always lit up, if engineers strategically place LUNARSABERs around the surface of the Moon, there should always be at least one in full sunlight. That one sunlight tower could then wirelessly transmit power to another tower in its line of sight. That process could continue until the power is beamed back to the main Artemis base, providing power even in the cold lunar dark.

A LUNARSABER could serve as a streetlight on the Moon during its two week dark period, as show in this artist’s rendition.
Credit – Honeybee Robotics

Explorations on the other side of the Moon are also tricky, limiting the area of scientific inquiry primarily to the side directly facing us. However, a strategically set-up mesh of LUNARSABERS would allow communication back to Earth, even with assets exploring the “dark” side of the Moon that faces us. 

As Vishnu Sangiepalli, the PI on the LUNARSABER, put it in the recent video, “the best way to describe the LUNARSABER would be a Swiss Army Knife.” These multifunctional tools have been a mainstay in explorers’ pockets for decades, and LUNARSABER helps match their versatility and flexibility to solve the problems facing the new lunar explorers.

Learn More:
Sanigepalli et al. – LUNARSABER: Lunar Utility with Navigation, Advanced Remote Sensing, and Autonomous Beaming for Energy Redistribution
Honeybee Robotics – Honeybee Robotics to Develop LUNARSABER for DARPA’s LunA-10 Program
UT – Does Beaming Power in Space Make Sense at the Moon?
UT – Exploring the Moon’s Shadowed Regions Using Beamed Energy
UT – Wireless Power Transmission Could Enable Exploration of the Far Side of the Moon

Lead Image:
LUNARSABERS configured in a mesh network to beam power and communications to various points of interest on the lunar surface.
Credit – Honeybee Robotics

The post A Tower On The Moon Could Provide Astronauts With Light, Power, and Guidance appeared first on Universe Today.

Categories: Science

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