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Satellite images of the Antarctic Peninsula and nearby islands reveal that the area covered by vegetation grew dramatically between 1986 and 2021 and the rate of growth has accelerated since 2016

Dying of COVID is worse.

The post If Dr. Jay Bhattacharya Saw What I Saw, He’d Realize That Being Called “Fringe” Isn’t So Bad After All first appeared on Science-Based Medicine.

Researchers adopt a new ligand to enhance the efficiency and stability of perovskite quantum dot solar cells. Solar cell efficiency increases to 15.3% by correcting distortions on the surface of quantum dots.

Physical infrastructure on the Moon will be critical to any long-term human presence there as both America and China gear up for a sustained human lunar presence. Increasingly, a self-deploying tower is one of the most essential parts of that physical infrastructure. These towers can hold numerous pieces of equipment, from solar panels to communications arrays, and the more weight they can hold in the lunar gravity, the more capable they become. So it’s essential to understand the best structural set-up for these towers, which is the purpose of a recent paper by researchers at North Carolina State University and NASA’s Langley Research Center. 

Several technologies underpin that structure, which was developed under NASA’s Self-Erectable Lunar Tower for Instruments (SELTI) project. One of the most important technologies is the material the tower consists of. In their study, the researchers looked at two types of material: the corrugated rollable tubular boom (COROTUB) and collapsible tubular mast (CTM). 

Let’s consider the design around COROTUB first. COROTUB is a patented technology designed for use with small satellites. For example, it would allow a CubeSat to deploy an antenna many times its size while still being rolled into a relatively compact package. Adapting the technology to a deployable boom mast for use on the Moon is an obvious next step. 

Fraser discusses why we should go back to the Moon.

CTM, on the other hand, is commercially available from Opterus. It is designed to roll flat into a shape similar to a roll of tape. Once deployed, it is capable of supporting a payload located at the top of the mast. Its design seems much simpler than COROTUB’s, but on the surface, they have almost equivalent weight limits.

However, one of the most essential features of these towers doesn’t lie in the boom material itself but in the supporting structure – in this case, that is a cable. The paper looks at designs with and without supporting cables that could counteract the force of the instruments at the top of the boom, forcing them to slouch to one side. Imagine a giant sunflower with its pedals bending to one side, but on the other side, there’s a metal cable holding it in place.

The systems with this supporting cable structure perform superiorly by pretty much every metric the authors used. The methods they used included a type of mathematical analysis known as the Rayleigh-Ritz method, which is typically used to calculate loads on structures. But the math for those structures on the Moon is different from the same on Earth. For one, much less gravity and no wind would require additional support. 

Isaac Arthur assesses the possibilities of using the Moon as an industrial hub – presumably that would involve building towers.
Credit – Science and Futurism with Isaac Arthur YouTube Channel

However, the system must undergo massive temperature differences based on whether it is located on the lit or unlit side of the Moon. For now, those did not seem to be part of the calculations used in the analysis.

COROTUB and CMT are also not the only potential technologies looking to solve this problem. We previously reported on project LUNARSABER from Honeybee Robotics, whose 100m tall masts would solve a problem similar to the one addressed by COROTUB and CMT-based towers. While it remains to be seen which technology is used on a complete prototype on the Moon, the fact that more than one organization is looking into the technology is a good indication of promise. And since hosting literal lights is one of the use cases for these towers, it is only a matter of time before more light is shone on this technology – and the lunar surface underneath it.

Learn More:
J Daye, A Lee, & J Fernandez – Structural Architectures for Self-Erecting Lunar Towers
UT – A Tower On The Moon Could Provide Astronauts With Light, Power, and Guidance
UT – NASA’s New Solar Sail Extends Its Booms and Sets Sail
UT – A Moon Base Will Need a Transport System

Lead Image:
Artist’s conception of a Moon Base.
Credit – ESA – P. Carril

The post What’s the Best Material for a Lunar Tower? appeared first on Universe Today.

It’s not long before a conversation about space travel is likely to turn to the impact on the human body. Our bodies have evolved to exist on Earth with a constant force of 1G acting upon them but up in orbit, all of a sudden that force is apparently lacking. The impact of this is well known; muscle loss and reduction in bone density but there are effects of spaceflight. Cosmic radiation from the Galaxy has an impact on cognition too, an effect that has recently been studied in mice!

When an object like the space station is in orbit around the Earth it is in a state known as freefall. This means it is constantly falling to Earth but the curvature of the Earth is constantly falling away from it. In other words, it is constantly falling but never reaches the ground. This state means anyone or anything inside the space station would also fall at the same rate but this would be experienced as floating. Muscle loss and reduction in bone density are the well known impacts of such an environment but there are more that await a space traveller. 

ESA astronaut Alexander Gerst spent six hours and 13 minutes outside the International Space Station with NASA astronaut Reid Wiseman on Tuesday, 7 October 2014. This was the first spacewalk for both astronauts but they performed well in the weightlessness of orbit. Credit: NASA/ESA

Galactic cosmic radiation (GCR) is made up of energy originating from sources outside of our Solar System. These tend to be from supernova explosions and other energetic events in deep space. The particles from GCR are mostly protons and electrons along with some heavier nuclei. They can penetrate our atmosphere but the Earth’s magnetic field offers some protection to those on the surface. To those venturing out into space, things are a little less rosey for GCR can have quite an impact on astronauts. 

Sources of Ionizing Radiation in Interplanetary Space. The Radiation Assessment Detector (RAD) on NASA’s Curiosity Mars rover monitors high-energy atomic and subatomic particles coming from the sun, distant supernovae and other sources. The two types of radiation are known as Galactic Cosmic Rays and Solar Energetic Particles. RAD measured the flux of this energetic-particle radiation while shielded inside the Mars Science Laboratory spacecraft on the flight delivering Curiosity from Earth to Mars, and continues to monitor the flux on the surface of Mars. Credit: NASA/JPL-Caltech/SwRI

GCR is a real problem for longer duration space exploration like trips to Mars since currently, the radiation can penetrate spacecraft shielding and be a real threat to human health. Studies to date have shown that GCR can have an effect cognitive abilities on mice in the short term however a new study paints a rather more bleak picture. The paper published in the Journal of Neurochemistry reports that GCR exposure can have long lasting effects too. 

Surprisingly, the team studied the impact on both male and female mice by subjecting them to a multi-particle spectrum GCR similar to the radiation that would be experienced on a deep space mission. The experiment was undertaken at Brookhaven National Laboratory where a 33-ion beam was used to simulate radiation from space. The team found that the radiation impaired numerous central nervous system functions from memory, pattern separation (when the brain minimises overlap between patterns of neuronal activity that represents similar experiences), anxiety, vigilance, social novelty (tendency to spend time with a previously unknown mouse rather than a familiar mouse!) and motor controls.

The discovery that the impact on females was more pronounced was unexpected but the team also established that mice which were fed an antioxidant and anti-inflammatory drugs known as CDDO-EA were less effected. The findings will be of immediate benefit to space exploration but will also help us to understand the long term impact on our cognition from radiation.

Source : Can cosmic radiation in outer space affect astronauts’ long-term cognition?

The post What Does a Trip to Mars Do to the Brain? appeared first on Universe Today.

Liquefied natural gas leaves a greenhouse gas footprint that is 33% worse than coal, when processing and shipping are taken into account, according to a new study.

Researchers have developed a way to make one type of plastic material more durable and less likely to shed dangerous microplastics.

Looking deep into the early universe with NASA's James Webb Space Telescope, astronomers have found something unprecedented: a galaxy with an odd light signature, which they attribute to its gas outshining its stars. Found approximately one billion years after the big bang, galaxy GS-NDG-9422 (9422) may be a missing-link phase of galactic evolution between the universe's first stars and familiar, well-established galaxies.

For the first time, scientists have taken near-daily measurements of the Sun's global coronal magnetic field, a region of the Sun that has only been observed irregularly in the past. The resulting observations are providing valuable insights into the processes that drive the intense solar storms that impact fundamental technologies, and thus lives and livelihoods, here on Earth.

Could this be the next great comet? To be sure, these words have been said lots of times before. In a clockwork sky, how comets will perform is always the great wildcard. Comets from Kohoutek to ISON have failed to live up to expectations, while others like W3 Lovejoy took us all by surprise. But a discovery this past weekend has message boards abuzz, as an incoming sungrazer could put on a show right around Halloween.

Anatomy of a Sungrazer

The discovery comes to us from the prolific Asteroid Terrestrial-impact Last Alert System (ATLAS), which first spotted the comet on the night of September 27th. The initial designation of the comet was A11bP7I. The comet now has an official designation: C/2024 S1 ATLAS. This was announced on October 1st, in the International Astronomical Union’s Central Bureau for Astronomical Telegram’s message 5453.

The orbit of Comet C/2024 S1 ATLAS. Credit: NASA/JPL.

The highly eccentric hyperbolic orbit of the comet suggests it’s a member of the Kreutz family group of sungrazer comets. Most of these comets are doomed for destruction at perihelion, but there have been a few exceptions over the years. Those sungrazers that have survived have gone on to become great comets.

Could C/2024 S1 ATLAS do the same?

Comet Caveats

Now, a few caveats are in order. Astronomers found S1 ATLAS at +12th magnitude, 1.094 Astronomical Units (AU) from the Sun. It could well be the case that it simply had an outburst right when it was first spotted, and could in fact be smaller and less energetic than it seems. What we need are more observations over the next few weeks.

Comet C/2024 ATLAS imaged shortly after discovery. Credit: Michael Jaeger.

“It’s early days, so I think the prudent approach is to moderate our expectations and then be ‘pleasantly surprised’ later,” astronomer Karl Battams (U.S. Naval Research Laboratory) told Universe Today. “That said, there’s clearly the potential for this to be a very exciting comet. The best analog we have is comet Lovejoy in 2011, which was discovered just a couple of weeks from perihelion, versus this one which is nearly a month away.”

Comet S1 ATLAS imaged on September 28th. Credit: Filipp Romanov.

The comet reaches perihelion on October 28th, 0.0082 AU from the Sun. That’s 762,600 miles from solar center, just 330,600 miles from the surface of the Sun. The solar radius is about 432,000 miles. As always seems to be the case, southern hemisphere observers will get a better view of the comet leading up to perihelion in mid-October as it approaches the Sun through the constellation Hydra. The comet will be visible low to the east at dawn, and ‘could’ break +6th magnitude in the final week of October. The comet passes 0.306 AU from the Earth on October 23rd after which, things could start to get interesting.

Prospects for Sungrazer A1 ATLAS

As of writing this, best estimates for peak magnitudes for comet S1 ATLAS top out at -7—think a bright daytime comet, but very close to the Sun—though -1st magnitude or so is probably more conservative.

Northern hemisphere viewers might get best views of the comet low to the east at dawn after perihelion… if it survives.

Looking low to the east at dawn on Halloween morning. Credit: Starry Night.

“This Kreutz-group comet won’t pass quite as close to the Sun as W3 Lovejoy, so it’s not unreasonable to guess that it will aid its survival potential.” Says Battams. “Assuming so, it might be briefly visible to northern hemisphere observers very low in the early morning (in) southeast skies after perihelion, but it would require good viewing circumstances (a clear, low horizon)… and won’t hang around there for long.”

A simulation of Comet A1 ATLAS in SOHO’s field of view. Credit: Starry Night.

The comet enters the Solar Heliospheric Observatory (SOHO’s) LASCO C2/C3 field of view on October 26th, and exits on the 29th. It’s strange to think: prior to SOHO’s launch in 1995, astronomers knew of less than a handful of sungrazer comets. Now, thanks to the mission, we know of 5,065 sungrazing comets and counting.

New sticky: I rarely tweet these days, mainly b/c most of the fun people have left. ? But I still pop in from time-to-time, and will post about exciting comet or Sun stuff.
As always, any images/data I post are from 100% public sources, and all opinions are solely mine. pic.twitter.com/OeQRia2ppU

— Karl Battams (@SungrazerComets) October 2, 2024

Classic Sungrazers of Yore

2011’s sungrazer W3 Lovejoy survived a passage just 87,000 miles from the surface of the Sun… Comet ISON, however, did not survive a 0.001244 AU, 116,000 mile surface pass at perihelion on U.S. Thanksgiving Day 2013.

Long-time comet watchers will remember sungrazer Ikeya-Seki, which survived a 280,000 mile pass (just a little over the Earth-Moon distance) from the surface of the Sun. That comet went on to dazzle observers in 1965.

Comet Ikeya-Seki. Credit: James W. Young/TMO/JPL/NASA.

“What I will say is that I am very excited at the ‘prospect,’ and will be watching the evolution of this extremely closely over the next couple of weeks.” says Battams. “I think by mid-October we’ll be able to state some facts with a lot more certainty.”

It seems like good comets always come in pairs…remember Hale-Bopp and Hyakutake in the late 90s? We (finally) caught sight of comet C/2023 A3 Tsuchinshan-ATLAS this morning from here in Bristol, Tennessee, looking like a fuzzy ‘star’ with a short tail in the brightening twilight low to the east, peeking out between pine trees.

We’re cautious for now when it comes to S1 ATLAS. But remember: comets never read predictions… and S1 ATLAS could well surprise us.

The post Could a New Sungrazer Comet Put on a Show at the End of October? appeared first on Universe Today.

We’ve known the Universe is expanding for a long time. The first solid paper demonstrating cosmic expansion was published by Edwin Hubble in 1929, based on observations made by Vesto Slipher, Milton Humason, and Henrietta Leavitt. Because of this, the rate of cosmic expansion is known as the Hubble constant, or Hubble parameter, H0. From this parameter, you can calculate things such as the age of the Universe since the Big Bang, so knowing the value of H0 is central to our understanding of modern cosmology.

Early on, the measured value of the Hubble parameter varied widely. Hubble’s initial value was on the order of 500 (km/s)/Mpc. By the 1960s, the value settled down to between 50 and 90 (km/s)/Mpc, where it stayed for most of the 20th century. It was difficult to get more precise because our methods of calculating it were limited. All of these were based on the cosmic distance ladder, which uses a series of observations to calculate ever greater cosmic distances, each building on the previous method. But in the past few decades we got pretty good at it, and the Hubble value seemed to settle around 70 (km/s)/Mpc. After that, things started to get…problematic.

With satellites such as WMAP and Planck we started to get high-resolution maps of the cosmic microwave background. From fluctuations in this background we have a new way to measure H0 and get a value of 67 – 68 (km/s)/Mpc. At the same time, observations of distant supernovae and the cosmic distance ladder pin down the value to 73 – 75 (km/s)/Mpc. Both methods are quite precise, and yet they entirely disagree. This disagreement is now known as the Hubble tension problem, and it is the most bothersome mystery in cosmology.

Hubble tension between methods. Credit: Wikipedia user Primefac

We aren’t sure what causes the Hubble tension. It might mean that one or more of our observation methods are fundamentally flawed, or it might mean there is something about dark energy and cosmic expansion that we really don’t understand. But astronomers generally agree that one way to address this mystery is to look for ways to measure H0 that are independent of both the cosmic background and the cosmic distance ladder. One such method involves gravitational lensing.

Gravitational lensing occurs because gravity warps space, meaning that the path of light can be deflected by the presence of a large mass. So, for example, if a distant galaxy happens to be behind a closer galaxy from our vantage point, we see a gravitationally distorted view of the distant galaxy or even multiple images of the galaxy. The interesting thing about the multiple image effect is that the light from each image travels a different path around the closer galaxy, each with a different distance. Since the speed of light is finite this means each image gives us a view of the galaxy at different times in history.

This doesn’t matter much for galaxies, but for supernovae it means gravitational lensing can let us observe the same supernova multiple times. By calculating the path of each supernova image we can determine the relative distance of each path, and by timing the appearance of each image we can determine the actual distance. This gives us a measurement that is independent of the cosmic distance ladder, giving us a new way to measure the Hubble parameter. This method has been used a couple of times, but the uncertainties of their Hubble values weren’t small enough to address the Hubble tension. However, a new study using this method is precise enough.

The study is based on JWST images of a Type Ia supernova named SN H0pe. It is one of the most distant supernovae ever observed, and thanks to the less-distant galaxy cluster G165, the team captured three lensed images of SN H0pe. With their timing, observed brightness, and calculated paths, the team calculated H0 to be 70 – 83 (km/s)/Mpc. This still has a higher uncertainty than other methods, but it agrees with the usual distance ladder method. It also clearly disagrees with the cosmic microwave background method.

Despite H0pe, the Hubble tension is very real. If anything, this new result makes the issue even more troublesome. There is something about cosmic expansion we don’t understand, and it’s now clear that better observations will not solve this mystery on their own.

Reference: Pascale, Massimo, et al. “SN H0pe: The First Measurement of H0 from a Multiply-Imaged Type Ia Supernova, Discovered by JWST.” arXiv preprint arXiv:2403.18902 (2024).

The post Gravitational Lens Confirms the Hubble Tension appeared first on Universe Today.

The first 18 satellites of a planned Chinese mega constellation are brighter than all but 500 stars in the sky, raising fears of a huge impact on astronomy

Mathematicians have developed a recipe for upgrading quantum computers to simulate complex quantum systems, such as molecules. Their discovery brings us closer to being able to predict how new drugs will behave within our bodies and has the potential to revolutionize pharmaceutical development.

Increasingly complex applications such as artificial intelligence require ever more powerful and power-hungry computers to run. Optical computing is a proposed solution to increase speed and power efficiency but has yet to be realized due to constraints and drawbacks. A new design architecture, called diffraction casting, seeks to address these shortcomings. It introduces some concepts to the field of optical computing that might make it more appealing for implementation in next-generation computing devices.

Increasingly complex applications such as artificial intelligence require ever more powerful and power-hungry computers to run. Optical computing is a proposed solution to increase speed and power efficiency but has yet to be realized due to constraints and drawbacks. A new design architecture, called diffraction casting, seeks to address these shortcomings. It introduces some concepts to the field of optical computing that might make it more appealing for implementation in next-generation computing devices.

Deposits of ice in lunar dust and rock (regolith) are more extensive than previously thought, according to a new analysis of data from NASA's LRO (Lunar Reconnaissance Orbiter) mission. Ice would be a valuable resource for future lunar expeditions. Water could be used for radiation protection and supporting human explorers, or broken into its hydrogen and oxygen components to make rocket fuel, energy, and breathable air.

Physicists have succeeded in coupling two Andreev qubits coherently over a macroscopic distance for the first time. They achieved this with the help of microwave photons generated in a narrow superconducting resonator. The results lay the foundation for the use of coupled Andreev qubits in quantum communication and quantum computing.

Physicists have succeeded in coupling two Andreev qubits coherently over a macroscopic distance for the first time. They achieved this with the help of microwave photons generated in a narrow superconducting resonator. The results lay the foundation for the use of coupled Andreev qubits in quantum communication and quantum computing.

A chip-based 'tractor beam' can trap and manipulate biological particles using a tightly focused beam of light emitted from a silicon-photonics chip. The device could help biologists and clinicians study DNA, classify cells, and investigate the mechanisms of disease.

A chip-based 'tractor beam' can trap and manipulate biological particles using a tightly focused beam of light emitted from a silicon-photonics chip. The device could help biologists and clinicians study DNA, classify cells, and investigate the mechanisms of disease.