News Feeds

The Chinese social media apps Red Note and Lemon8 have become popular alternatives for TikTok users ahead of a US government ban on TikTok. But government restrictions loom over those apps too

There’s plenty of action at the center of the galaxy, where a supermassive black hole (SMBH) known as Sagittarius A* (Sgr A*) literally holds the galaxy together. Part of that action is the creation of gigantic flares from Sgr A*, which can give off energy equivalent to 10 times the Sun’s annual energy output. However, scientists have been missing a key feature of these flares for decades – what they look like in the mid-infrared range. But now, a team led by researchers at Harvard’s Center for Astrophysics and the Max Planck Institute for Radio Astronomy has published a paper that details what a flare looks like in those frequencies for the first time.

Astronomers have been observing Sgr A* since the 1990s and have known about the flares, which were initially seen as variances in the SMBH’s brightness. It has been observed with all manner of telescopes, including the Chandra X-ray observatory and, perhaps most famously, the Event Horizon Telescope, which was responsible for the famous first image of M87*, another black hole at the center of the Messier galaxy. EHT also released an image from Sgr A* itself in May of 2022.

So far, those observations have been in visible light through infrared and from far infrared up through X-rays. There has always been a gap in the middle of the infrared range. Several factors explain this gap.

Fraser talks about imaging Sgr A*

First, Sgr A* is relatively weak in the mid-infrared range compared to other ranges, so it doesn’t stand out as much against the background noise of the universe. Second, much of the mid-infrared emissions get obscured by the dust cloud surrounding the SMBH at the galaxy’s center, blocking it from detectors at Earth 28,000 light years away. Third, there were technological limitations to infrared sensors themselves. There were ground-based telescopes that could have detected the signal, but the Earth’s atmosphere blocked even more of it.

That required scientists to wait for the long-delayed James Webb Space Telescope (JWST). When it finally launched in late 2021, it was only a matter of time before they would get observational time to watch Sgr A* and hopefully observe a flare with the most powerful infrared detector ever launched into orbit. 

JWST did indeed get observational time with Sgr A* and saw a flare, representing the first-ever recording of a flare in the mid-infrared range. But the research team didn’t stop there – they were also watching with several other telescopes for confirmation of the JWST signal.

Fraser talks about other features of Sgr A*

They didn’t find any in the X-ray range with Chandra, though that was probably because the flare wasn’t strong enough to emit a significant amount of X-rays. But they did see a signal from the Sub-Millimeter Array (SMA) in Hawai’i, which detected radio waves following along about 10 minutes behind the detected mid-infrared signal.

That confirmation was necessary because it allowed the experimentalists to provide even more insight about the same flare to the theoreticians. Their job is then to confirm the models and simulations of what causes the flares in the first place. The current theory is that they occur when magnetic field lines in the SMBH’s accretion disk join up and emit massive amounts of radiation in a process known as synchrotron emission. In synchrotron emission, a bunch of charged particles – typically electrons – get pushed down the magnetic field lines like they were part of a massive particle accelerator.

The data from JWST fits nicely into that theory. However, there appear to be additional unanswered questions about whether that feature was specific to Sgr A* or whether it could be observed for other SMBHs such as M87*. For now, that remains to be seen, though given the interest in this particular black hole in this specific wavelength, while this might have been the first study published on the topic, it probably won’t be the last.

Learn More:
CfA – Scientists Make First-Ever Detection of Mid-IR Flares in Sgr A*
von Fellenberg et al – First mid-infrared detection and modeling of a flare from Sgr A*
UT – Echoes of Flares from the Milky Way’s Supermassive Black Hole
UT – A Black Hole Emitted a Flare Away From us, but its Intense Gravity Redirected the Blast Back in our Direction

Lead Image:
This artist’s conception of the mid-IR flare in Sgr A* captures the variability, or changing intensity, of the flare as the black hole’s magnetic field lines approach each other. The byproduct of this magnetic reconnection is synchrotron emission. The emission seen in the flare intensifies as energized electrons travel along the SMBH’s magnetic field lines at close to the speed of light. The labels mark how the flare’s spectral index changes from the beginning to the end of the flare.
Credit: CfA/Mel Weiss

The post Astronomers See Flares Coming from the Milky Way’s Supermassive Black Hole appeared first on Universe Today.

My hospital just reinstituted mask mandates for all staff working with patients. They also advise patients to wear masks while in the hospital, but have not made it a requirement. I still have a stash of N95 masks so it was easy, and all too familiar, for me to comply, but I admit it created an unpleasant flash-back. All things considered, I […]

The post COVID Is Still Here, But Changing first appeared on Science-Based Medicine.

Middle-aged mice fed golden oyster mushrooms had healthier hearts, suggesting an antioxidant in the fungi protects against the effects of ageing

Meanwhile, in Dobrzyn, Hili knows if you’ve been naughty or nice:

Hili: I can see everything.
A: What do you see?
Hili: You are sneaking chocolate again.
A: I have an important reason.

Hili: Ja wszystko widzę.
Ja: Co widzisz?
Hili: Znowu podjadasz czekoladę.
Ja: Mam ważny powód.

A newly discovered neutron star is behaving so strangely that it may alter our understanding of the dense remains left behind when stellar objects die

A tiny asteroid loitering in a near-Earth orbit for a few months last year may have an intriguing origin on our Moon. Its characteristics led scientists to ask: is it a chip off the old lunar block, making a pass by Earth for a visit?

The object is known as Near-Earth Asteroid (NEA) 2024 PT5 (or PT5, for short) and its orbit is very similar to Earth’s. Oddly enough, that region often gets littered with rocket bodies. Interestingly, it’s also a region where debris blasted off the Moon during impacts tends to collect. So, could PT5 have come from the Moon? There’s a good chance that it did but how do we know this?

An artist’s impression of a lunar explosion, caused by the impact of a meteorite on the surface of the Moon. Such an impact could have created asteroid PT5. Credit: NASA/Jennifer Harbaugh

Planetary scientists have long studied Near-Earth objects (NEOs) and NEAs to understand their origins. One way to do that is to determine a relationship between their current orbits, properties, and sources, One such origin is the Main Asteroid Belt, but it’s not the only place where asteroids emerge. Each object is a special case, and scientists compare them with known meteorites. Of course, you need some data about the object’s physical characteristics—including its reflectance and albedo. Those two properties can often tell you what part of an asteroid population the object came from. They’re particularly important if there are no physical samples available for analysis.

Looking at Spectra of the Suspected Moon Chunk

A team of observers used the Lowell Discovery Telescope in Flagstaff, Arizona, to take reflectance spectra of PT5. This 10-meter-wide chunk of space rock was first discovered in August of 2024 by a survey project in South Africa. Its orbit made it a perfect target for another survey called MANOS (Mission Accessible Near-Earth Object Survey). The Lowell observations took place a week later to determine reflectance properties. Those are useful to figure out its origin—either natural or artificial. Subsequent observations of the object characterized its rotation and revealed it has a rocky, silicate-rich composition. That ruled out an artificial origin.

The reflectance spectrum from the Lowell telescope does give a match to known lunar samples. PT5 does not match any known asteroid types, however. For example, it looks to be pyroxene-rich, which indicates the rock came from an igneous or possibly metamorphic environment. Other asteroids aren’t the same—they tend to be richer in olivine. Based on that data and its tumbling motion, scientists conclude that it is ejecta from an impact on the Moon. If that’s the case, it’s only the second time a NEA has been found that came from the Moon.

Reflectance data from a MANOS survey of NEA 2024 PT5 made on January 7, 2025. Courtesy MANOS/Lowell Observatory.

If only one existed, we could say it’s a space oddity. However, the presence of two such objects changes the story. It also suggests that there’s a whole population out there waiting to be observed.

What PT5 Means

So, let’s say there is this collection of lunar chunks floating around out there. They can give insight into how impacts affect the Moon or other bodies such as Earth and Mars. They would also help identify the sources of other asteroids and meteorites from this under-studied population of near-Earth objects. In a paper discussing PT5, authors Theodore Kareta of Lowell Observatory, Oscar Fuentes-Munoz from NASA JPL, and others, describe their study of this rock, its orbit, and physical characteristics. They write, “If there really is a population of Moon Rocks out there waiting to be discovered on near-Earth orbits, they almost certainly are rare members of the NEO population.”

There may well be only about 16 currently known NEOs that could have come from the Moon, but there could be more. Now, the challenge is to separate them from the general population of near-Earth objects and subject them to further study. Since the orbits of lunar ejecta pieces tend to evolve into Aten- or Apollo-type orbits, the authors point out there could be between 5 and 10 times more of these lunar chips off the old block in the neighborhood. (Aten asteroids are a group known as “Earth-crossing” asteroids because their orbits cross our planet’s orbit. Apollo asteroids also follow orbits that cross ours.)

Three classes of asteroids that pass near Earth or cross its orbit are Apollo, Aten and Amor. Apollo asteroids like 2014 SC324 routinely cross Earth’s orbit, Atens also cross but have different orbital characteristics and Amors cross Mars’ orbit but miss Earth’s. Credit: ESA Future Observations of Suspected Moon Pieces

If there is a larger population of lunar-sourced asteroids in near-Earth-type orbits, then the next step is to figure out ways to find them. Certainly, asteroid surveys will help, along with further observations of their reflectance and charts of their orbits. Since these asteroids are generally thought to be relatively small, it will take a new generation of larger telescopes and observational techniques to find them.

Probably one of the greatest results of the search for these objects is what they can tell us about impact histories in the inner solar systems. The paper’s authors point this out. “First at Mars and now at the Earth, the impact histories of the terrestrial planets appear to be partially encoded in the asteroids that orbit nearby to them. Future work to discover more of and measure the properties of this population of near-Earth objects which are sourced by the Moon will be critical to link asteroid and lunar science in the era of Artemis and the Vera Rubin Observatory’s LSST.”

The next chance to observe PT5 is coming up this month when it lingers near Earth again. NASA has plans to track it with radar and undoubtedly others will be studying it to understand more about this “mini-Moon”.

For More Information

On The Lunar Origin of Near-Earth Asteroid 2024 PT5
NASA to Track Asteroid 2024 PT5 on Next Close Pass, January 2025

The post Earth’s Temporary Moon Might Have Come from THE Moon appeared first on Universe Today.

A fuzzy form of dark matter may clump up to become the cores of galaxies, according to new research.

The traditional dark matter hypothesis, that it’s some form of cold, massive particle that hardly ever interacts with itself or with normal matter, has some difficulties. In particular, it can’t quite explain the dense cores of galaxies. Cold, heavy dark matter tends to produce extremely dense cores, far denser than what we observe.

But dark matter might be something else. Recently astronomers have hypothesized that dark matter might instead be incredibly light, far lighter than any known particle. This “fuzzy” dark matter would allow the quantum wave nature of the particles to manifest on macroscopic – even galactic – scales, allowing them to form large, diffuse clumps known as “dark stars.”

Dark stars can be incredibly huge, stretching for thousands of light-years, while still having relatively low density. This would match observations of galaxy cores, which makes this an intriguing hypothesis to follow.

In a recent letter appearing in the preprint server arXiv in December, an international collaboration of astrophysicists explored how galaxies might evolve in response to fuzzy dark matter. For this first step, they did not attempt to fully recreate an entire complex galaxy. Instead they built a simple toy model containing only two components: a large fraction of fuzzy dark matter and a smaller fraction of a simple, ideal gas.

They then simulated how these two components would interact with each other and evolve. They found that no matter how they start off, normal matter and fuzzy dark matter quickly find an equilibrium, with the two kinds of matter mixing together to make a large, stable core, surrounded by a cloud of dark matter.

The researchers pointed out that this would serve as the ideal representation of a galactic core, which contains higher – but not too high – densities of normal matter. This is the first step to confirming a key prediction of the fuzzy dark matter model. However, there is still a lot of work to be done. The next step is to build even more realistic simulations of the growth and evolution of galaxies, tracking how fuzzy dark matter, and the dark stars they create, influences their local environments. Then we can take those results and compare to observations to see if this idea is worth investigating even more.

The post Galaxy Cores May be Giant Fuzzy Dark Stars appeared first on Universe Today.

After the Big Bang came the Dark Ages, a period lasting hundreds of millions of years when the universe was largely without light. It ended in the epoch of reionization when neutral hydrogen atoms became charged for the first time and the first generation of stars started to form. The question that has perplexed astronomers is what caused the first hydrogen atoms to charge. A team of researchers have observed an early quasar that pumped out enormous amounts of x-ray radiation helping to drive the reionization. 

The universe began with the Big Bang around 13.8 billion years ago, starting as a hot, dense point that was infinitely small. In the first few minutes, light elements like hydrogen and helium formed, and a few hundred million years later – possibly as early as 380,000 years, the Cosmic Microwave Background (CMB) marked the end of the Dark Ages. Gravity then pulled matter together, forming the first stars and galaxies during the Epoch of Reionization. These early stars ionized hydrogen, making the universe transparent. Over billions of years, galaxies merged and structures formed, with our solar system emerging around 4.6 billion years ago. 

The full-sky image of the temperature fluctuations (shown as color differences) in the cosmic microwave background, made from nine years of WMAP observations. These are the seeds of galaxies, from a time when the universe was under 400,000 years old. Credit: NASA/WMAP

The transition between the Dark Age and the Reionization phase has been the subject of study by a team of astronomers from Yale University. They have detected intense periods of brightening and dimming of a quasar about 12 billion light years away. The observation sheds some light on the accelerated rate of growth experienced by some objects in the early universe.

The quasar identified by the team goes by the catchy title J1429+5447. It’s found in the constellation of Lyra and is so far away that its light takes 12 billion years to reach us, this means we see it now as it was just 1.6 billion years after the Big Bang. Studying it gives us a real insight into the early evolution of the universe. At its centre is a supermassive black hole which accretes matter and in the process emits intense amounts of radiation across the whole electromagnetic spectrum. The team announced their discovery on 14 January at a meeting of the American Astronomical Society. 

Artist’s impression of a quasar core. Quasars are powered by interactions between supermassive black holes and their accretion disks at the hearts of galaxies. JWST observed one in infrared light to reveal its feeding mechanism. Courtesy T. Mueller/MPIA.

Using NuSTAR, an X-ray space telescope to study the quasar they compared their observations with previous studies 4 months earlier using the Chandra X-ray telescope. To their surprise, in just 4 months, the X-ray emissions from the quasar doubled! 

The spectral ranges of the XMM-Newton and NuSTAR Telescopes. (Credits: NASA, ESA)

Meg Urry, Professor of Physics and Astronomy and co-author explained ‘The level fo X-ray variability in terms of intensity and rapidity is extreme.  It is almost certainly explained by a jet pointing toward — a cone in which particles are transported up to a million light years away from the central, supermassive black hole. Because the jet moves at nearly the speed of light, effects of Einstein’s theory of special relativity speed up and amplify the variability.”

The team believe these early quasars like J1429+5447 provided the energy to end the Dark Ages and herald in the Reionisation period. Their study has revealed how crucial quasars were to the early evolution of the universe.

Source : This quasar may have helped turn the lights on for the universe

The post This Quasar Helped End the Dark Ages of the Universe appeared first on Universe Today.

When a new space telescope is launched, it’s designed to address specific issues in astronomy and provide critical answers to important questions. The JWST was built with four overarching science goals in mind. However, when anticipating new telescopes, astronomers are quick to point out that they’re also excited by the unexpected discoveries that new telescopes make.

There has been no shortage of unexpected discoveries regarding the JWST, especially regarding the very early Universe.

In December 2022, after the JWST had been performing science operations for just six months, the telescope revealed the presence of small red objects in the high-redshift sky. Astronomers called them Little Red Dots (LRDs). The nature of these objects wasn’t obvious, but they’re abundant, and astronomers are curious about what they can tell us about the early Universe.

Recently, a team of researchers compiled a large sample of these LRDs. Most of them existed only 1.5 billion years after the Big Bang. According to observations, a large number of the LRDs may contain growing supermassive black holes (SMBHs). There is no class of corresponding objects at lower redshifts, which only deepens their mysterious nature.

The new research is “The Rise of Faint, Red AGN at z>4: A Sample of Little Red Dots in the JWST Extragalactic Legacy Fields.” It’s been accepted for publication in The Astrophysical Journal, and the lead author is Dale Kocevski of Colby College in Waterville, Maine. The paper is available on the pre-print server arxiv.org.

“We’re confounded by this new population of objects that Webb has found. We don’t see analogs of them at lower redshifts, which is why we haven’t seen them prior to Webb,” said lead author Kocevski. “There’s a substantial amount of work being done to try to determine the nature of these little red dots and whether their light is dominated by accreting black holes.”

The JWST has generated an enormous amount of data during its observations. The astronomers behind the sample of LRDs used publicly available data from the CEERS, PRIMER, JADES, UNCOVER and NGDEEP surveys. While they’re not the first to probe datasets for LRDs, the team used a different methodology that identified LRDs over a wider redshift range. They identified 341 LRDs spanning from about redshift 2 to 11. The researchers found that LRDs emerged in large numbers only 600 million years after the Big Bang, before their number rapidly around 1.5 billion years after the Big Bang.

These images from the research show a subset of the 341 Little Red Dots from the various surveys. Image Credit: Kocevski et al. 2024.

Fortunately, some spectroscopic data are already available for a portion of the LRDs in the Red Unknowns: Bright Infrared Extragalactic Survey (RUBIES), which contains JWST/NIRSpec spectroscopy of red sources. The spectroscopic data showed that about 70% of the LRDs show evidence of rapidly rotating gas. The gas is moving at about 1,000 km per second, indicating that these could be accretion disks around supermassive black holes.

The conclusion seems pretty clear: LRDs are active galactic nuclei (AGN), which are black holes that are actively feeding. But why do they peter out after about 1.5 billion years after the Big Bang?

“The most exciting thing for me is the redshift distributions. These really red, high-redshift sources basically stop existing at a certain point after the big bang,” said Steven Finkelstein, a co-author of the study at the University of Texas at Austin. “If they are growing black holes, and we think at least 70 percent of them are, this hints at an era of obscured black hole growth in the early universe.”

Most of us remember when some overeager headlines claimed that the JWST had “broken cosmology.” The discovery of LRDs was responsible for some of this thinking. If the light coming from the LRDs was from stars, then some galaxies had to have grown very large very fast. Our theories couldn’t account for them.

If these results are true, then the light is coming from active galactic nuclei rather than large, rapidly growing galaxies. In this case, our theories are safe (for now).

“This is how you solve the universe-breaking problem,” said Anthony Taylor, a co-author of the study at the University of Texas at Austin.

In their paper, the authors highlight some of their important points.

“One of our primary findings is that the red compact objects that have come to be known as little red dots appear in large numbers at z > 4,” they write. “The redshift distribution that we observe for our sample of LRDs may provide insight into the nature of their obscuration and the mechanisms fueling their nuclear activity.”

This figure shows the redshift distribution of the final sample of LRDs in the research. Image Credit: Kocevski et al. 2024.

Their obscuration could result from what’s called “inside-out growth.” In that model, stars begin forming in a galaxy’s central regions first, and they are created more rapidly in those regions. Eventually, star birth moves outward to a galaxy’s periphery. This is because gas collapses inward due to gravity, fuelling star birth in the center. That same collapsing gas could also trigger the concurrent growth of the galaxy’s SMBH. This can also explain the red colour we see. “The rapid accumulation of metals in the proto-bulge then provides the reddening we observe,” the authors write.

As star birth moves outward, less dust is deposited near the AGN, meaning that over time, there are fewer LRDs.

However, inside-out growth is only one potential explanation for LRDs, though it’s a good fit with much of the existing data. The team intends to follow up on this work with mid-infrared imaging and spectroscopy. That will help them understand the number density of these faint AGN and shed more light on what’s obscuring them.

“There’s always two or more potential ways to explain the confounding properties of little red dots,” said Kocevski. “It’s a continuous exchange between models and observations, finding a balance between what aligns well between the two and what conflicts.”

Whatever exactly is going on with LRDs, the issue shows how powerful unexpected discoveries can be. It also shows, again, how valuable the JWST is.

“While much remains to be determined about the nature of LRDs, the prevalence of broad emission lines in their spectra suggests this population is shedding light on a phase of obscured black hole growth in the early universe that was largely undetected prior to the JWST era,” the authors conclude.

The post Webb Provides an Explanation for “Little Red Dots” appeared first on Universe Today.

Obesity is typically assessed by measuring someone's body mass index, but now researchers are calling for a more nuanced approach that could help with treatment

Scientists describe their construction of complementary, internal, ion-gated, organic electrochemical transistors that are more amenable chemically, biologically and electronically to living tissues than rigid, silicon-based technologies. The medical device based on these transistors can function in sensitive parts of the body and conform to organ structures even as they grow. The result is a biocompatible sensor that can monitor brain functions in pediatric patients as they develop and grow.

Scientists describe their construction of complementary, internal, ion-gated, organic electrochemical transistors that are more amenable chemically, biologically and electronically to living tissues than rigid, silicon-based technologies. The medical device based on these transistors can function in sensitive parts of the body and conform to organ structures even as they grow. The result is a biocompatible sensor that can monitor brain functions in pediatric patients as they develop and grow.

Researchers have published a study describing how quasiparticles called polarons behave in tellurene, a nanomaterial first synthesized in 2017 that is made up of tiny chains of tellurium atoms and has properties useful in sensing, electronic, optical and energy devices.

Researchers have published a study describing how quasiparticles called polarons behave in tellurene, a nanomaterial first synthesized in 2017 that is made up of tiny chains of tellurium atoms and has properties useful in sensing, electronic, optical and energy devices.

Federal reservoirs could help meet the country's solar energy needs, according to a new study. Geospatial scientists and senior legal and regulatory analyst quantified exactly how much energy could be generated from floating solar panel projects installed on federally owned or regulated reservoirs.

I’ve lost count of the number of times I have seen the Ring Nebula. It’s a favourite amongst stargazers around the globe and is surely one of the most well known objects in the night sky. The remains of a Sun-like star, its outer layers have drifted out into space leaving behind a the stellar corpse, a white dwarf. It looks like a giant smoke ring in the sky but what is its true shape? A team of astronomers have mapped carbon monoxide that surrounds the nebula and built a 3D model to reveal its shape. 

The Ring Nebula is a wonderful example of a planetary nebula. It’s located in the constellation Lyra, about 2,000 light-years from Earth and its progenitor star shed its outer layers 6,000 years ago leaving behind the core to become a hot white dwarf. Intense ultraviolet radiation from the white dwarf excites the surrounding gas, causing it to emit green and blue light due to ionized oxygen and nitrogen. It was discovered by Charles Messier who was hunting for comets and, as he spotted objects which clearly weren’t comets he cataloged them. The Ring Nebula is the 57th object in his catalogue so it has the designation M57.

JWST/NIRcam composite image of the Ring Nebula. The images clearly show the main ring, surrounded by a faint halo and with many delicate structures. The interior of the ring is filled with hot gas. The star which ejected all this material is visible at the very center. Courtesy JWST/University of Manchester.

A team of astronomers led by Chester F. Carlson from the Rochester Institute of Technology and Professor Joel Kastner from the Centre for Imaging Science and School of Physics and Astronomy have been exploring the shape of M57. They used the Submillimeter Array (SMA) to map the emission of carbon monoxide gas in the nebula. The carbon monoxide surrounds the hot gas and dust that appears in classic images we are all familiar with seeing. 

The Submillimeter Array (SMA) is a radio telescope located on top of Mauna Kea in Hawaii and was designed to observe the universe at submillimeter wavelengths. It is made up of eight 6-meter radio dishes arranged as an interferometer. It enables astronomers to capture high-resolution images of distant objects such as star-forming regions, galaxies, and molecular clouds by detecting the emission of faint submillimeter radiation.

This image shows two of the Atacama Large Millimeter/submillimeter Array (ALMA) 12-metre antennas. ALMA has 66 antennas that work together as an interferometer. (Credit : Iztok Bonina/ESO)

For decades, since the nebula was first photographed in 1886, astronomers have been wondering just what shape the nebula was. A dust ring shape or something resembling a soap bubble structure were the favourite models but the results from SMA observations reveal an ellipsoid structure. The team were able to draw this conclusion from analysing the velocity and location of carbon monoxide molecules from the SMA data. They would have been ejected by the star in its death-throws to reveal its shape to us today. 

The findings are similar reminiscent of observations of the Southern Ring Nebula in the constellation Vela. It was one of the first objects observed by the JWST and the results revealed more about its structure just like its more familiar northern counterpart. One slight difference is that the team observing M57 didn’t expect that the SMA data would also reveal the influence of a companion star to the progenitor red giant. They found high velocity concentrations of gas that were ejected out each end of the ellipsoidal nebula. 

Source : RIT professor leads research showing true structure of the iconic Ring Nebula

The post Astronomers Reveal the 3D Structure of the Ring Nebula appeared first on Universe Today.

From 2000 to 2022, the US legally imported almost 30,000 different species of plants and animals, from songbirds to reptiles

Climate scientists must fear sounding like a broken record when discussing new record temperatures yearly. But once again, last year was the hottest one ever recorded, according to a new study by NASA scientists.

Anyone paying close attention to climate news would not be surprised. From June 2023 through August 2024, every consecutive month broke a new monthly temperature record. That is 15 straight months of consistently high temperatures. 

Such a streak directly translates into the year’s overall temperature, but just how bad was it? The Paris Agreement on climate change, signed by 195 countries and the European Union, attempts to limit the global rise in temperatures to 1.5? over a baseline temperature from the middle of last century (1951-1980). 2024 was already 1.28? above it. 

That’s not a great start, but the data gets even more dire for the climate-conscious. Temperatures in 2024 were already 1.47? above a baseline of temperatures from 1850-1900, a time before the industrial revolution, or automobile transportation, had taken off. Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies, says, “That’s halfway to Pliocene-level warmth in just 150 years.”, referring to a geological period where a baseline temperature of just 1.5? above the Earth’s 2024 average resulted in sea levels that were tens of meters higher than total.

Such a sea level rise would devastate population centers home to literally billions of people and have such a dramatic effect on sea and wildlife that it’d be hard to predict the consequences. But it’s not like any of this information is new—it’s just worth reinforcing.

Even with reinforcement, more action is needed to solve the problem. The last ten years have been the warmest on record. While there is some variability between years, the trend in warming temperatures is obvious. Despite that, in 2022 and 2023, there were record releases of carbon dioxide from fossil fuels.

Even 12 years ago, Fraser and Pamela were discussing climate change and what it meant for the planet.

Additional effects could have impacted such a hot year in 2024. A NASA press release mentions everything from El Niño to volcanoes in Tonga to improved sulfur dioxide emissions from cargo ships. All undoubtedly impact the climate, but the contribution of each is difficult to tease out.

NASA’s global temperature assessment is based on data from thousands of weather stations scattered throughout the globe, both on land and sea. The same data was analyzed by other organizations, such as the US’s National Oceanic and Atmospheric Administration, Berkeley Earth, the Hadley Centre, and Copernicus Climate Services. Each used slightly different methodologies and models to determine the Earth’s temperature last year. Still, each showed a trend toward hotter temperatures – which most scientists take as unambiguous proof that the planet is getting hotter.

However, many naysayers still can’t see the forest for the trees, as a nasty cold snap could convince them of the illusion of “global warming” in general. However, the world’s overall temperature shift is getting drastic enough that local areas are literally starting to feel the heat. Schmidt said, “When changes happen in the climate, you see it first in the global mean, then you see it at the continental scale, and then at the regional scale. Now we’re seeing it at the local level.”

The fires currently threatening NASA’s Jet Propulsion Laboratory in Pasadena are just one symptom of the ongoing environmental challenges facing the world. This NASA report is just the most recent in a long line of reports that all point to the same conclusion—the world is getting warmer, and we humans are likely the ones causing it. 

Learn More:
NASA – Temperatures Rising: NASA Confirms 2024 Warmest Year on Record
UT – NASA Confirms that 2023 was the Hottest Year on Record
UT – NASA Confirms That 2023 was the Hottest Summer on Record
UT – Global Temperatures Continue to Rise

Lead Image:
This map of Earth in 2024 shows global surface temperature anomalies, or how much warmer or cooler each region of the planet was compared to the average from 1951 to 1980. Normal temperatures are shown in white, higher-than-normal temperatures in red and orange, and lower-than-normal temperatures in blue. An animated version of this map shows global temperature anomalies changing over time, dating back to 1880. Download this visualization from NASA Goddard’s Scientific Visualization Studio: https://svs.gsfc.nasa.gov/5450.
Credit: NASA’s Scientific Visualization Studio

The post It’s Official, 2024 Was the Hottest Year on Record appeared first on Universe Today.

Carbon-rich cosmic dust comes from different sources and spreads out into space, where it’s necessary for life and for the formation of rocky planets like ours. When astronomers aim their telescopes at objects in the sky, they often have to contend with this cosmic dust that obscures their targets and confounds their observations.

One reason the JWST was built is to see through some of this dust with its infrared vision and unlock new insights into astrophysical processes. In new work, the JWST was tasked with observing the dust itself.

The Wolf–Rayet binary WR 140 is about 5,000 light-years away in the constellation Cygnus. In 2022, researchers published results in Nature Astronomy revealing details about the binary star. The results showed that the stellar winds from both stars regularly collide, producing rings of carbon-rich dust that expand outward from the stars.

“We are used to thinking about events in space taking place slowly, over millions or billions of years. In this system, the observatory is showing that the dust shells are expanding from one year to the next.”

Jennifer Hoffman, co-author, University of Denver

“Massive colliding-wind binaries that host a Wolf–Rayet (WR) star present a potentially important source of dust and chemical enrichment in the interstellar medium,” the authors wrote, noting that the dust’s chemical composition and how it survives are still not understood. “The carbon-rich Wolf–Rayet binary WR 140 presents an ideal astrophysical laboratory for investigating these questions, given its well-defined orbital period and predictable dust-formation episodes every 7.93?years around periastron passage,” the authors explained in their research.

The environment near these stars when they’re close to one another is chaotic, even hostile. The winds from these evolved stars are chemically rich, and when the stronger wind from the WR star collides with the wind from the OB star, the gas is compressed, and dust is produced. Since the dust is only produced at periastron, the dust forms discrete rings. “Galactic colliding-wind WC (Wolf-Rayet stars of the carbon sequence) binaries with resolvable circumstellar dust nebulae, therefore, provide important laboratories to study this dust-formation process, where observations over the past few decades have demonstrated how dust formation is regulated by the orbit of the binary system,” the authors of the 2022 paper explain.

The pair of massive stars, one a Wolf-Rayet and one an OB star, orbit one another and reach periastron every 7.93 years. That’s when the powerful stellar winds from both stars collide. Astronomers think that evolved Wolf-Rayet stars and their colliding winds might be responsible for some of the first carbonaceous dust grains and organic material in the Universe.

The JWST captured the original 2022 images about 5.5 years after the last periastron in 2016. Now, about 14 months after the JWST’s initial look at WR 140, the space telescope has taken another long look at the interacting binary and its concentric rings of expanding carbon-rich dust. The images show how much the rings have expanded in less than two years time.

“The telescope confirmed that these dust shells are real, and its data also showed that the dust shells are moving outward at consistent velocities, revealing visible changes over incredibly short periods of time,” said Emma Lieb, the lead author of the new paper and a doctoral student at the University of Denver in Colorado.

Compare the two mid-infrared images taken by the James Webb Space Telescope of Wolf-Rayet 140, a system of dust shells ejected by two massive stars that are in an elongated orbit. In the top right of the first two images, two triangles are matched up to show how much the rings have moved in 14 months. The dust is moving away from the stars at more than 2,600 km per second, about 1% of the speed of light. The rings of carbon-rich dust are created for a few months every eight years. Image Credit: NASA, ESA, CSA, STScI, E. Lieb (University of Denver), R. Lau (NSF NOIRLab), J. Hoffman (University of Denver)

It’s relatively rare to see astronomical objects exhibit change on short timescales like this. For only 14 months, every eight years, the stellar winds collide and produce the visible carbon-rich dust rings. While WR binaries are known to produce carbon-rich dust, most pairs aren’t this active and their periastrons are much further apart in time.

“We are used to thinking about events in space taking place slowly, over millions or billions of years,” added Jennifer Hoffman, a co-author and a professor at the University of Denver. “In this system, the observatory is showing that the dust shells are expanding from one year to the next.”

“Seeing the real-time movement of these shells between Webb’s observations that were taken only 13 months apart is truly remarkable,” said Olivia Jones, a co-author at the UK Astronomy Technology Centre, Edinburgh. “These new results are giving us a first glimpse of the potential role of such massive binaries as factories of dust in the Universe.”

Astronomers have spotted other WC stars producing dust rings. However, WR 140 exceeds them all. “The extent of these distant circumstellar shells detected around WR 140 exceeds that of all other known dust-forming WC systems by factors of 4 or greater,” the authors of the 2022 paper explain.

The stars follow wide, elongated orbits, and when their winds collide every eight years, they produce carbon-rich dust for several months. The JWST’s powerful MIRI imaged dust rings that date back more than 130 years. Shells older than that have dissipated into interstellar space and are no longer coherent and visible. Some of that material may have already been taken up in star formation.

Thanks to MIRI, the researchers learned that WR 140 will likely generate tens of thousands of dust shells over hundreds of thousands of years.

“Mid-infrared observations are absolutely crucial for this analysis, since the dust in this system is fairly cool. Near-infrared and visible-light observations would only show the shells that are closest to the star,” explained Ryan Lau, a co-author and astronomer at NSF NOIRLab in Tucson, Arizona. Lau led the initial research on this system in 2022. “With these incredible new details, the telescope is also allowing us to study exactly when the stars are forming dust — almost to the day.”

These JWST images don’t show it, but not all of the dust is in the form of rings. Some of it is in clouds larger than our entire Solar System. Some of it floats freely as individual dust particles, each one only one-hundredth the width of a human hair. In all cases, the dust is carbon-rich and moving at the same speed.

One estimate says that the rings are about 1.4 trillion km apart. For comparison, if our Sun were creating these shells, one shell would be about five percent of the distance to Alpha Centauri, our nearest neighbour, before the next shell was created.

Eventually, the creation of carbon-rich dust shells will cease. Most WR stars end their lives as supernovae, with some possibly collapsing directly into black holes.

But that’s in the distant future. In humanity’s direct future, WR 140 will keep producing these carbon-rich dust shells, and the JWST will keep watching this natural laboratory to see how it all happens.

The post The Webb Shows Us Where Cosmic Dust Comes From appeared first on Universe Today.