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Breakthrough in scalable production of high-quality organoids

Computers and Math from Science Daily Feed - Mon, 11/25/2024 - 9:58am
Introducing the innovative 'UniMat' platform utilizing 3D engineered nanofiber membrane.
Categories: Science

Brighter and more efficient LEDs that don't droop

Matter and energy from Science Daily Feed - Mon, 11/25/2024 - 9:58am
LEDs with low polarization in a direction similar to standard LEDs show greater efficiency at higher power by resisting 'efficiency droop', a new study shows. The findings open the door to a new generation of efficient, high-powered LED lighting which exceeds the capabilities of existing systems.
Categories: Science

Scientists produce high-power attosecond X-ray pulses at megahertz repetition rates

Matter and energy from Science Daily Feed - Mon, 11/25/2024 - 9:51am
A research team has achieved a major advance in X-ray science by generating unprecedented high-power attosecond hard X-ray pulses at megahertz repetition rates. This advancement opens new frontiers in the study of ultrafast electron dynamics and enables non-destructive measurements at the atomic level.
Categories: Science

ODS FeCrAl alloys endure liquid metal flow at 600 °C resembling a fusion blanket environment

Matter and energy from Science Daily Feed - Mon, 11/25/2024 - 9:51am
Researchers explored protective coatings to resist corrosion in fusion reactors. They tested -Al2O3 oxide layers on ODS alloys in a high-temperature, flowing lithium-lead environment. Even bare ODS alloys formed a durable -LiAlO2 layer in situ, which suppressed further corrosion. The layers exhibited strong adhesion under mechanical stress, making these findings crucial for improving material durability in fusion reactors and high-temperature energy systems.
Categories: Science

The future of edge AI: Dye-sensitized solar cell-based synaptic device

Computers and Math from Science Daily Feed - Mon, 11/25/2024 - 9:51am
Physical reservoir computing (PRC) utilizing synaptic devices shows significant promise for edge AI. Researchers from the Tokyo University of Science have introduced a novel self-powered dye-sensitized solar cell-based device that mimics human synaptic behavior for efficient edge AI processing, inspired by the eye's afterimage phenomenon. The device has light intensity-controllable time constants, helping it achieve high performance during time-series data processing and motion recognition tasks. This work is a major step toward multiple time-scale PRC.
Categories: Science

The next evolution of AI begins with ours

Computers and Math from Science Daily Feed - Mon, 11/25/2024 - 9:50am
The genome has space for only a small fraction of the information needed to control complex behaviors. So then how, for example, does a newborn sea turtle instinctually know to follow the moonlight? Neuroscientists have devised a potential explanation for this age-old paradox. Their ideas should lead to faster, more evolved forms of artificial intelligence.
Categories: Science

Using sunlight to recycle black plastics

Matter and energy from Science Daily Feed - Mon, 11/25/2024 - 9:50am
Not all plastics are equal -- some types and colors are easier to recycle than others. For instance, black foam and black coffee lids, which are often made of polystyrene, usually end up in landfills because color additives lead to ineffective sorting. Now, researchers report on the ability to leverage one additive in black plastics, with the help of sunlight or white LEDs, to convert black and colored polystyrene waste into reusable starting materials.
Categories: Science

Impact of climate change on water resources will increase price tag to decarbonize the grid

Matter and energy from Science Daily Feed - Mon, 11/25/2024 - 9:50am
A new study warns that current plans to achieve zero emissions on the grid by 2050 vastly underestimate the required investments in generation and transmission infrastructure. The reason: these plans do not account for climate change's impacts on water resources. Specifically, changes in water availability caused by climate change could decrease hydropower generation by up to 23% by the year 2050, while electricity demand could increase by 2%.
Categories: Science

Researchers use fitness tracker data and machine learning to detect bipolar disorder mood swings

Matter and energy from Science Daily Feed - Mon, 11/25/2024 - 9:49am
Investigators evaluated whether data collected from a fitness tracker could be used to accurately detect mood episodes in people with bipolar disorder.
Categories: Science

New AI tool generates realistic satellite images of future flooding

Computers and Math from Science Daily Feed - Mon, 11/25/2024 - 9:49am
With help from AI, scientists developed a method that generates satellite imagery from the future to depict how a region would look after a potential flooding event.
Categories: Science

Novel supernova observations grant astronomers a peek into the cosmic past

Space and time from Science Daily Feed - Mon, 11/25/2024 - 9:48am
An international team of researchers has made new observations of an unusual supernova, finding the most metal-poor stellar explosion ever observed.
Categories: Science

Most energetic cosmic-ray electrons and positrons ever observed

Matter and energy from Science Daily Feed - Mon, 11/25/2024 - 9:47am
Scientists have recently identified electrons and positrons with the highest energies ever recorded on Earth. They provide evidence of cosmic processes emitting colossal amounts of energy, the origins of which are as yet unknown.
Categories: Science

Most energetic cosmic-ray electrons and positrons ever observed

Space and time from Science Daily Feed - Mon, 11/25/2024 - 9:47am
Scientists have recently identified electrons and positrons with the highest energies ever recorded on Earth. They provide evidence of cosmic processes emitting colossal amounts of energy, the origins of which are as yet unknown.
Categories: Science

Testing the Robots that Might Explore Europa

Universe Today Feed - Mon, 11/25/2024 - 9:02am

Europa, one of the four Galilean satellites of Jupiter is one of the most intriguing locations in the Solar System to search for life. However, its subsurface oceans are buried beneath thick layers of ice making exploration difficult. To explore its oceans, scientists have suggested using small swimming robots capable of penetrating the icy shell. Recently, NASA engineers tested prototypes designed to operate as a swarm, enabling them to explore the mysterious sub-ice oceans on Europa and other icy worlds in the Solar System.

Along with the other three Galilean satellites orbing Jupiter, Europa was discovered just over 400 years ago by Galileo. It is the smallest of the four measuring just 3,120 km across. It orbits Jupiter at a distance of 671,000 km in an almost circular orbit. In comparison to our own Moon, Europa is a little smaller but that is where the similarities end. Europa is made of a silicate rock and has a thick water ice crust below which is thought to be a liquid water ocean and it is this which has captured the interest of scientists. 

The Galilean moons of Jupiter: Io, Europa, Ganymede, and Callisto. (Credit: NASA/JPL-Caltech)

The deep oceans of Europa may well harbour forms of aquatic life. Consider the deepest parts of the oceans of Earth where whole eco-systems thrive off thermal vents. At these depths, no light from the Sun penetrates so the organisms and creatures living at these depths take all their energy from the heat escaping from inside the planet.  It is this which tantalisingly suggests that maybe such life could have evolved in the oceans of Europa too.

A black smoker hydrothermal vent discovered in the Atlantic Ocean in 1979. It’s fueled from deep beneath the surface by magma that superheats the water. The plume carries minerals and other materials out to the sea. Courtesy USGS.

The exploration of Europa is already underway with NASA’s Europa Clipper expected to arrive in 2030. It will explore Europa with a powerful set of scientific instruments over a total of 49 flybys. Each pass will see the instruments search for signs that the ocean under the thick icy crust could sustain life. This will just be a flyby mission with Europa being probed from high above its surface. NASA are already shaping up their next mission to include even more complex robots that could survey the depths of the sub-surface oceans of Europa.

Artist’s concept of a Europa Clipper mission. Credit: NASA/JPL

This is where NASA’s new mission called SWIM ‘Sensing With Independent Micro-swimmers’ comes in. The concept at least, is simple…a swarm of self-propelled robots that can swim around in the underground oceans having been deployed by the ice piercing cryobot. Once underway, the swimming robots, which are about the size of a mobile phone, would hunt for chemical and temperature signals that might indicate life.

The swimming robots are not just on the drawing board. Engineers have already used 3D printers to create prototypes that have already been tested in a 23 metre pool. The devices which are propelled along by two propellers, with flaps for steering were able to stay on course. These prototypes however were a little larger than those destined to make it into space measuring about three times larger. 

The results of the test were very promising but much more work is needed before they are ready for launch. Meanwhile the robots are likely to be trialled here on Earth to support oceanographic research before being sent on their way to Europa. 

Source : NASA Ocean World Explorers Have to Swim Before They Can Fly

The post Testing the Robots that Might Explore Europa appeared first on Universe Today.

Categories: Science

In a jeremiad that scientists should be political activists, Agustín Fuentes conflates science with scientists

Why Evolution is True Feed - Mon, 11/25/2024 - 9:00am

Agustín Fuentes is a biological anthropologist at Princeton University, and has appeared in these pages more than a couple of times, for he is also somewhat of a “progressive activist” who, for example, has indicted Darwin for being a racist and espoused the view that sex is non-binary (see video below).   In the latest issue of Science, he justifies his activism, asserting that scientists should be political and ideological activists because this helps us fight what he sees as an encroaching attack on science that will accompany the Trump administration.

But Fuentes’s short letter is deeply confusing, for it conflates the idea of scientists being activists with science itself being activist. I’ll give some quotes to show that conflation, and then give my disagreement with the ideas that science should be activist, as well some reservations with the notion that it’s generally good for scientists to be activists. Click below to read the letter, ironically classified under “expert voices”:

First Fuentes implies that his promotion of activism in science and among scientists in this piece came explicitly because of the threat he sees posed by the Trump administration:

Science, both teaching and doing, is under attack. The recent US presidential election of a person and platform with anti-science bias exemplifies this.

That itself is a problem, as it’s not going to win over half of America (see below).

But to some extent I agree with this, for it certainly looks as scientific truth will be endangered by Trump and, especially, his appointments in the area of public health and science.

Certainly scientists who see their field as endangered are entitled to speak out as individuals against stuff like climate-change denial, vaccine denialism, and opposition to GMOs and nuclear energy.  When politicians or other scientists present misleading data to support a political  position, it is scientists who know the data to correct the record. After all, that is one of the great benefits of science: it is self-correcting.

But of course correcting the record, for example giving data showing that nuclear energy can replace fossil fuels, is not the same things as saying okay, we have to replace fossil fuels with nuclear energy now.  For fixing problems often requires expertise beyond the ambit of scientists: things like political savvy, economic and practical considerations, and so on. Ergo, accepting a scientific argument is not always identical to saying that we must go ahead and fix society according to the “winning” scientific assertion, for in the long run such fixes may be more harmful than helpful. (Note: I am not saying we should keep using fossil fuels as much as we do: this is just an example!)

But I digress. I want to show how Fuentes conflates the activism of scientists as individuals with the activism of science as an institution, something he does throughout the letter (bolding is mine):

Whether science is political, and if it should be, is an age-old debate. Some assert that scientific institutions and scientists themselves should seek to remain apolitical, or at least present a face of political neutrality. Others argue that such isolation is both impossible and unnecessary, that scientists are and should be in the political fray.

Notice that he conflates scientists with scientific institutions, the latter including scientific organizations, journals, and granting institutions.

Here’s more:

The Editor-in-Chief of Science recently wrote that although science has always been political, it “thrives when its advocates are shrewd politicians but suffers when its opponents are better at politics.” Given the current political reality and the expansion of attacks on science, it is time for scientists to be more effective, forceful, and vociferous as their own political advocates.

Who is supposed to be political here—science itself or scientists?  It’s clear that he means scientists, but also throws “science” into the mix as he does in the last sentence of the excerpt below. It’s also clear that the activism he wants from scientists is progressive left-wing activism, presumably of the kind that Fuentes himself has promoted in his previous articles. I don’t think he’s calling for right-wing scientists to be activists!

There are many taking vocal stances asserting key scientific findings and practices in the face of attacks by anti-science forces. Most scientists are familiar with the prominent cases of Anthony Fauci or Peter Hotez in public health, and of Michael Mann in climate science. But for every one of the high-profile examples, there are other, less publicly known attacks on scientists and science educators working in public spheres, social media, and the classroom. These attacks are often especially intense when the scientists are also womenBIPOC (Black, Indigenous, and people of color), queer, or from other marginalized groups. The increasingly anti-science political ecosystem creates a dire need for science to be proactive, not only reactive.

More conflation:

If one’s job, salary, research support, etc. are at risk, it is not surprising that one may not want to “stick their neck out.” And such threats will grow in the US under the incoming administration. There also remains some prominent fear of the term “political” in the scientific community, as if being political represents a bad thing or something that diminishes the value of science or the scientist.

Finally, here’s Fuentes’s final pronouncement that science itself should become a vehicle for promoting a social mission, almost certainly the “progressive mission of the left”:

As the social scientists Fernando Tormos-Aponte, Scott Frickel, and John Parker discovered in a survey just after the 2020 US elections, for many scientists “political advocacy is no longer anathema to scientific research, but should be embraced as a central aspect of science’s social mission.” This is even more true here at the end of 2024.

Once again this conflates what scientists should do with how we conceive of the “social mission of science”, that is, we should change our view of science to make activism a part of it.

Fuentes doesn’t seem to realize, as we know from statistics about the public’s view of science and of universities, that there is indeed a danger to scientists and to science itself from scientists taking stands in particular venues, like journals or professional societies. We know that when Nature endorsed Joe Biden for President in 2020, it not only did not convince more people to vote for him, but reduced the credibility of the journal, and of science itself, in the eyes of readers. When Scientific American became activist, publishing article after article taking “progressive” stands, including two misguided pieces by Fuentes himself, it lost credibility in the eyes of many and, in the end, the editor-in-chief left the journal, probably because she had no choice.  What was the cause of the final rupture between the magazine and the editor? Her attacks on Bluesky against supporters of Trump.

Finally, we know that public trust in science among both Democrats and Republicans has declined significantly in the last decade, and there’s been an even steeper drop in public confidence in colleges and universities.

Now of course you’ve surely said to yourself, “But there is no impersonal ‘science’ that takes stands. It must be the scientists themselves who do.” And of course that’s correct.  But what I am trying say is that there are ways and ways of scientists being activists, and some of them are useful but others are not. My points are below:

a.) Scientists should use their recognized expertise to correct false arguments that affect society. For example, if vaccines are effective and we have data on their efficacy, and we also have data that they don’t cause autism, we should say so.  But arguments are more effective when the scientists making them are experts in the area, which leads to the next point:

b.) Scientists should shy away from making scientific arguments outside their sphere of expertise. A prime example of this is evolutionary biologist Bret Weinstein, who has severely hurt his own reputation by making statements about covid vaccines and touting the efficacy of ivermectin as both a treatment for and preventive of Covid.  Weinstein did not know what he was talking about, and had no good data to back up his claims. He was dead wrong, but of course people used his statements to justify using horse de-wormer for their virus infection. Such statements may well harm or even kill people.

c.) Scientists should not make arguments that they say are scientific if they are imbued with ideology. This only serves to turn off a public who may know better. Luana and I deal with six of these arguments in the paper by me and Luana Maroja in Skeptical Inquirer, including rejection of the sex binary, claims that there are no evolved differences between males and females, and the idea that indigenous knowledge should be considered coequal with modern science. Ideology based arguments in these areas are misleading and injurious to the public understanding of science.

d.) “Science” itself should not be seen as incorporating activism as a necessary component.  Sure, scientists can use their knowledge to cure diseases like Covid, or create vaccines to fight polio. If you see that as “activism”, well, it’s not a form of activism that is very injurious, since nobody wants those diseases around. However, there will still be opposition to vaccination, and part of that, for covid, was due to scientists themselves either not being straightforward with data (not good) or changing their recommendations based on changing understanding of the virus and its transmission (a normal party of science).

Here are some forms of activism that can be seen as part of science itself and should be avoided:

1.) Scientific journals, magazines, or societies making ideological statements (viz. Lancet, the Society for the Study of Evolution. etc. saying that sex is a spectrum)

2.) Scientific organizations using ideology to dispense scientific funding, for example using criteria other than merit to advance “equity”.

3.) Scientists claiming the authority of science when advancing what is are biased and ideological views (see my paper with Luana).

4.) Scientists hiring other scientists or accepting graduate students based on criteria other than merit (ee #2).

In general, science gets eroded when its practitioners elevate criteria other than merit, including ethnicity, gender, or Marxist beliefs in human malleability.

Now all of these, in my view, have the potential to damage science itself, as well as to damage universities, in which science education plays a large part.  When people see the criteria above violated, they become more anti-science and more anti-university. They are less willing to support science or to give their kids (or themselves) higher education.

It is largely the ideological neutrality of “science itself”, as ideally instantiated in science departments, science journals, granting agencies, and science societies and organizations, that has kept the reputation of science unsullied.  But now it is getting sullied, and sullied from both the right and left. One of the reasons for this is the very activism that Fuentes wants so badly.

As I said, scientists have an important role to play in improving society, but that role should, as far as possible, be limited to ensuring that the data fed into societal arguments be as accurate as possible. When scientists go beyond that, infusing their data with ideology, the potential for harm to their brand is very real.  This doesn’t mean that scientists shouldn’t have free speech, for of course they should and they do.  What it means is that unless they speak carefully, and avoid a partisan bias, they risk the reputation of the very fields they love.

In the five-minute video below we see Fuentes being an ideologue while at the same time arguing that science shouldn’t “become ideology”.  He mischaracterizes atheism as saying ‘I know for sure there is no god,”  argues that evolutionary biology is imbued with racism and sexism, and maintains that the sex binary “is not the best way to characterize humans.” Yes, humans are messy and vary in their gender, but the sex binary, as I’ve argued, applies as much to humans as it does to any other animal. There are exactly two sexes, and there are no more than two sexes. Yes, Dr. Fuentes, the world is “complex and messy”, but I don’t buy your claim that the sex binary itself somehow misrepresents or distorts our knowledge of variation in human behavior or culture. After all, the sex binary is just a definition, and one that has the advantage of holding universally in all animals and vascular plants. It has nothing to say about culture or variation in behavior.

From the YouTube notes:

This interview is an episode from ‪@The-Well‬, our publication about ideas that inspire a life well-lived, created with the ‪@JohnTempletonFoundation‬.

Templeton! Wouldn’t you know it?

h/t: Anna and Luana, my partners in crime

Categories: Science

Einstein Predicted How Gravity Should Work at the Largest Scales. And He Was Right

Universe Today Feed - Mon, 11/25/2024 - 8:01am

When Albert Einstein introduced his theory of general relativity in 1915, it changed the way we viewed the Universe. His gravitational model showed how Newtonian gravity, which had dominated astronomy and physics for more than three centuries, was merely an approximation of a more subtle and elegant model. Einstein showed us that gravity is not a mere force but is rather the foundation of cosmic structure. Gravity, Einstein said, defined the structure of space and time itself.

But in the past century, we have learned far more about the cosmos than even Einstein could have imagined. Some of our observations, such as gravitational lensing clearly confirm general relativity, but others seem to poke holes in the model. The rotational motion of galaxies doesn’t match the predictions of gravity alone, leading astronomers to introduce dark matter. The expansion of the Universe is not steady but is accelerating, pointing to the presence of dark energy. For some astronomers, this points to the need for a new model. Something that can account for the motions of stars and galaxies without the need for those dark materials that remain undetected in the lab. The most popular alternatives focus on theories of modified gravity.

The standard model of cosmology is known as the LCDM model. The L, for lambda, is the symbol used in general relativity to represent the rate of cosmic expansion and represents dark energy, while CDM stands for cold dark matter. This model describes an expanding Universe that began as a hot, dense state about 13.78 billion years ago. It is a Universe made up of about 5% regular matter, 25% dark matter, and 70% dark energy. It is currently the model best supported by observational evidence. Modified gravity models have a big hill to climb. To topple LCDM they have to account for everything it predicts as well as eliminate the need for dark matter and energy.

Observations confirm the validity of general relativity and the standard model of cosmology. Credit: The DESI Collaboration.

This year, that hill has become much steeper. In a series of publications released by the Dark Energy Spectroscopic Instrument (DESI) collaboration, the standard cosmological model has been confirmed to be in complete agreement with Einstein’s model. The DESI survey mapped nearly six million galaxies across 11 billion years of cosmic time, allowing astronomers to see not just how galaxies cluster but how that clustering changes over time. It is the largest 3D map of the Universe made thus far.

The LCDM model makes very stringent predictions of cosmic structure. If dark energy were a kind of repulsive force rather than an inherent property of spacetime, clustering would evolve differently than observed. If dark matter was an illusion of modified gravitational forces, the scale of galactic clustering would be different. This latest survey shows in explicit detail that modified gravity models don’t hold up. The results strongly constrain which modified gravity models are possible and rule out many of the models currently proposed. Based on these new results, the standard cosmological model of Einsteinian gravity, dark matter, and dark energy is the one that best fits the observed Universe.

There are still mysteries that still need to be solved, most significantly the issue of the Hubble tension problem. Perhaps a novel modified gravity model will solve this mystery and finally topple Einstein, but for now, the wild-haired genius remains king of the hill.

Reference: Adame, A. G., et al. “DESI 2024 II: Sample Definitions, Characteristics, and Two-point Clustering Statistics.” arXiv preprint arXiv:2411.12020 (2024).

Reference: Adame, A. G., et al. “DESI 2024 V: Full-Shape Galaxy Clustering from Galaxies and Quasars.” arXiv preprint arXiv:2411.12021 (2024).

Reference: Adame, A. G., et al. “DESI 2024 VII: Cosmological Constraints from the Full-Shape Modeling of Clustering Measurements.” arXiv preprint arXiv:2411.12022 (2024).

The post Einstein Predicted How Gravity Should Work at the Largest Scales. And He Was Right appeared first on Universe Today.

Categories: Science

How a unique puppy kindergarten lab put the science into dog training

New Scientist Feed - Mon, 11/25/2024 - 8:01am
Most dogs aren't bred to feel at ease in our homes, but scientists studying puppy cognition have found ways you can help yours adapt
Categories: Science

This start-up is removing carbon from a polluted New York City river

New Scientist Feed - Mon, 11/25/2024 - 8:00am
Projects to remove carbon dioxide from the atmosphere by making the oceans less acidic are popping up all over the world – New Scientist visited one in New York City’s East river
Categories: Science

Watch the Crescent Moon Occult Spica for North America Early Wednesday Morning

Universe Today Feed - Mon, 11/25/2024 - 7:24am

One of the best bright star lunar occultations for 2024 occurs this week, as the Moon covers Spica.

Have you ever seen the Moon blot out a star? If the weather cooperates, early morning viewers across eastern North America have a chance to see a rare spectacle, as the crescent Moon occults (covers) the bright star Spica.

When to Watch

The event is centered on the early morning hours of Wednesday, November 27th at 12:16 Universal Time (UT)/7:16 AM EST/6:16 AM CST. The International Occultation Timing Association (IOTA) has a list of ingress/egress times for select sites in the occultation footprint. The IOTA also has a more technical discussion of the event here. The Moon is a -13% illuminated, waning crescent (just four days from New) during the event, meaning that Spica will ingress on the daytime lit side, and egress along the nighttime dark limb of the Moon.

The occultation visibility footprint for Wednesday morning’s event. The solid lines denote where the event is visible under dark skies, blue is twilight, and broken lines means the event occurs under daytime skies. Credit: Occult 4.2. The ‘Wow Factor’

It’s a strange celestial scene: like during a total solar eclipse, you’re standing in the shadow of the Moon… but in this case, it’s ‘cast’ by +1st magnitude Spica… from 250 light-years away. Also known as Alpha Virginis as the brightest star in the constellation Virgo, Spica also holds the distinction of a contender for a nearby galactic supernova event in the far future.

Cloud cover percentage prospects for Wednesday morning. Credit: NOAA/NWS.

Occultations are interesting and important to astronomers, as they give us a chance to analyze both objects involved. In the case of the star, we might notice the teeny angular diameter as it winks out, perhaps briefly revealing a faint secondary companion. In the case of Spica, its apparent size is 0.906 milliarcseconds, and is a spectroscopic binary with a close companion star in a close four day orbit.

Going to the Grazeline

An occultation can also help to map out the jagged limb or profile of the Moon. This works as the star blinks in and out of view. Imagine the star playing peek-a-boo with mountain peaks, shining down lunar valleys. The southern grazeline to see such a spectacle Wednesday morning crosses Texas, New Mexico and Arizona and is not to be missed.

The grazeline limit across the southwestern U.S. Credit: IOTA The ‘Spica Cycle’

Spica is one of the four bright stars that lies along the path of the Moon in the current epoch. The other three are Aldebaran, Regulus and Antares. Like eclipses, these occur in cycles. The Moon covers the star once per every 29.5 day synodic lunation. This continues until the track of the Moon carries it slowly away. In 2024 into 2025, the Moon is also occulting Antares as well. Also, like eclipses, the track for occultations moves 120 degrees west in longitude from one event to the next.

Observing and Imaging

Spica is bright enough to track near the Moon right up into the bright dawn, just before sunrise. The event also lends itself well to video capture. You’ll be able to easily see Spica disappear and reappear using binoculars… or even with just the unaided eye. The star will be much more prominent along the dark nighttime limb of the Moon.

Faint, but there… Spica near the daytime Moon. Credit: Dave Dickinson.

In a slow-moving Universe, occultations give us a chance to see change occurring in a split second. Don’t miss ‘The Great American Occultation,’ as Spica disappears behind the Moon Wednesday morning, and the celestial drama of the sky above us continues.

The post Watch the Crescent Moon Occult Spica for North America Early Wednesday Morning appeared first on Universe Today.

Categories: Science

NASA Releases its Moon Phases Animation for 2025

Universe Today Feed - Mon, 11/25/2024 - 6:06am

Every year, NASA releases a detailed simulation of the Moon that shows how it will change through the year. They produce a couple of versions that show how it appears from the northern and southern hemisphere and others that highlight different features. Not only does it show the phases through the year but it also shows the change in size as its completes its orbit. The change in apparent size of the Moon is a result of its elliptical orbit so that it can appear up to 30% brighter. 

The Moon is Earth’s only permanent natural satellite. It has captivated humans for thousands of as it orbits at an average distance of 384,400 kilometres. It plays a key role in shaping our tides through its gravitational pull. The lunar surface is a desolate, rocky world with colossal mountains, and plains known as maria.  It has no atmosphere and so experiences extreme temperature shifts, from intense solar heating in the day to freezing cold at night. Over the centuries, it has inspired countless myths and driven exploration that has culminated in the Apollo missions and soon Artemis. 

Global map of the Moon, as seen from the Clementine mission, showing the lunar near- and farside. If we’re going back to the Moon, we’ll need a Lunar GPS. Credit: NASA.

One of the most well known aspects of the Moon are the lunar phases. The phases of the Moon represent its motion around the Earth and its changing appearance when viewed from Earth. The cycle lasts about 29.5 days and is known as a lunar month. It begins with a new moon when the Moon lies approximately between Earth and the Sun and appears nearly invisible as we look at the night time hemisphere. 

The bright sunlit crescent contrasts with the darker lighting of twice-reflected light supplied by sunlight reflecting off our own planet. Credit: Bob King

As the cycle continues the crescent appears, getting larger and larger marking the waxing crescent phase. Eventually it leads to a first quarter phase when half of the Moon appears illuminated. It increases through the waxing gibbous phase before reaching full moon. The cycle then reverses through the waning phases to new moon again. 

The phases appear nicely in the video from NASA but what is also apparent is the gentle rocking of the Moon. Known as libration, it means we get to see slightly more than 50% of the lunar surface, 59% over time. The phenomenon occurs due to the axial tilt of the Moon and its elliptical orbit. It can be categorised as three different types; longitudinal (caused by changes in Moon’s orbital speed,) latitudinal (caused by tilt in the Moon’s axis) and diurnal (caused by Earth’s rotation and a slight shift in position of observer.)

The video simulation produced by NASA has been created from images taken by the Lunar Reconnaissance Orbiter (LRO.) It has been in orbit since the summer of 2009 and has produced images of unprecedented quality. Using advanced instruments, it has mapped the surface in high detail, revealing detailed topography, temperature, and geological maps. It has identified landing sites, especially near the poles, where water ice may exist, and has captured images of some of the Apollo landing sites.

Artist’s rendering of Lunar Reconnaissance Orbiter (LRO) in orbit. Credit: ASU/LROC

The animation shows the phases, and libration at hourly intervals until the end of 2025. One month is compressed down into about 24 seconds to give a comprehensive view of the year ahead.

Source : NASA Moon Animation

The post NASA Releases its Moon Phases Animation for 2025 appeared first on Universe Today.

Categories: Science

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