Universe Today

It’s coming back! Sunspot AR3664 gave us an amazing display of northern lights in mid-May and it’s now rotating back into view. That means another great display if this sunspot continues to flare out. It’s all part of solar maximum—the peak of an 11-year cycle of solar active and quiet times. This cycle is the result of something inside the Sun—the solar dynamo. A team of scientists suggests that this big generator lies not far beneath the solar surface. It creates a magnetic field and spurs flares and sunspots.

For a long time, solar physicists thought the magnetic dynamo was deep inside the Sun. That view may change thanks to work by researchers at MIT, the University of Edinburgh, the University of Colorado, Bates College, Northwestern University, and the University of California. The dynamo may be related to instabilities in what’s called the “near-surface shear layer” in the Sun’s outermost regions. The activities in this layer result in the flares and sunspots we see more of as the Sun nears “solar maximum”. Flares are high-energy outbursts while sunspots are surface features with local magnetic fields. Sunspots are relatively cool regions on the solar surface and occur in 11-year cycles.

NASA’s Solar Dynamics Observatory captured these images of the solar flares — as seen in the bright flashes in the upper right — on May 5 and May 6, 2024. The image shows a subset of extreme ultraviolet light that highlights the extremely hot material in flares and which is colorized in teal. The loops are magnetic field lines channeling plasma. Credit: NASA/SDO

“The features we see when looking at the Sun, like the corona that many people saw during the recent solar eclipse, sunspots, and solar flares, are all associated with the sun’s magnetic field,” said MIT researcher Keaton Burns. “We show that isolated perturbations near the sun’s surface, far from the deeper layers, can grow over time to potentially produce the magnetic structures we see.”

How is the Sun’s Magnetic Field Connected to Activity?

To understand the magnitude of this finding, let’s look at the structure of the Sun. We all know the Sun is a superheated ball of plasma. So, how does boiling plasma create a magnetic dynamo? “One of the basic ideas for how to start a dynamo is that you need a region where there’s a lot of plasma moving past other plasma and that shearing motion converts kinetic energy into magnetic energy,” Burns explained. “People had thought that the Sun’s magnetic field is created by the motions at the very bottom of the convection zone.”

The interior structure of our Sun. The dynamo generating a magnetic field could lie very close to the solar surface. Credit: Kelvin Ma, via Wikipedia

Of course, pinning down the exact location of the solar dynamo in the upper layers is difficult. Simulations can only go so far, and modeling the plasma flow throughout the entire Sun is a massive computing task. So, Burns and the team decided simulate a smaller piece of the Sun. They studied the stability of plasma flow near the solar surface. That required helioseismology data showing vibrations on the Sun’s surface, which allowed them to determine the average flow of plasma in that region. “If you take a video of a drum and watch how it vibrates in slow motion, you can work out the drumhead’s shape and stiffness from the vibrational modes,” said Burns. “Similarly, we can use vibrations that we see on the solar surface to infer the average structure on the inside.”

Think of the Sun as layered like an onion. Different plasma layers rush past each other as the Sun rotates, according to Burns. “Then we ask: Are there perturbations, or tiny changes in the flow of plasma, that we could superimpose on top of this average structure, that might grow to cause the sun’s magnetic field?”

Computing an Answer

The team developed algorithms that they incorporated into a numerical framework called the Dedalus Project. They looked for self-reinforcing changes in the Sun’s average surface flows. The algorithm discovered new patterns that could grow and result in realistic solar activity. Interestingly, those patterns also match the locations and timescales of sunspots. It turns out that certain changes in the flow of plasma at the very top of the Sun’s surface layers generate magnetic structures. This isn’t a new idea. Burns pointed out that the conditions there resembled the unstable plasma flows in accretion disks around black holes. Accretion disks are massive collections of gas and stellar dust that rotate in towards a black hole. They’re driven by “magnetorotational instability,” which generates turbulence in the flow and causes it to fall inward.

Burns and the team thought this phenomenon at a black hole might also be at work inside our Sun. They suggest that magnetorotational instability in the Sun’s outermost layers could be the first step in generating its magnetic field. “I think this result may be controversial,” he said. “Most of the community has been focused on finding dynamo action deep in the Sun. Now we’re showing there’s a different mechanism that seems to be a better match to observations.”

Implications of the New Model

Not only will the team’s work help solar physicists understand the creation of the magnetic dynamo, but may give them insight into other solar phenomena. In particular, a dynamo in the upper 10 percent of the Sun may explain things like the Maunder Minimum. This was a period between 1645 to 1715 when there were very few sunspots. In some years, observers saw no sunspots at all. In other years, they observed fewer than 20. Astronomers did chart the 11-year sunspot cycle through that time, so the Sun wasn’t entirely inactive.

If the Sun’s magnetic dynamo operates in its outermost layers, the science of solar activity forecasting could get a big boost. Right now, it’s difficult to tell when a flare might break out. Flares and coronal mass ejections like those that contributed to the May 10-11 geomagnetic storm can damage satellites and telecommunications systems here on Earth. In addition, power grids and other technology are at risk. In the long run, however, gaining new understanding of the Sun’s dynamo is a big deal.

“We know the dynamo acts like a giant clock with many complex interacting parts,” says co-author Geoffrey Vasil, a researcher at the University of Edinburgh. “But we don’t know many of the pieces or how they fit together. This new idea of how the solar dynamo starts is essential to understanding and predicting it.”

For More Information

The Origin of the Sun’s Magnetic Field Could Lie Close to Its Surface
The Solar Dynamo Begins Near the Surface

The post The Sun’s Magnetic Field Might Only Be Skin Deep appeared first on Universe Today.

Start talking about Venus and immediately my mind goes to those images from the Venera space probes that visited Venus in the 1970’s. They revealed a world that had been scarred by millennia of volcanic activity yet as far as we could tell those volcanoes were dormant. That is, until just now.  Magellan has been mapping the surface of Venus and between 1990 and 1992 had mapped 98% of the surface. Researchers compared two scans of the same area and discovered that there were fresh outflows of molten rock filling a vent crater! There was active volcanism on Venus. 

Venus is the second planet from the Sun and similar in size to Earth, the similarities end there though. It has a thick atmosphere that is toxic to life as we know it, there is sulphuric acid rain high in the atmosphere and a surface temperature of almost 500 degrees. When the Venera probes visited they measured an atmospheric pressure of around 90 times that at the Earth’s surface. Combined with the other hostile properties of the atmosphere, a human visitor would not survive long. 

Venus

The dense atmosphere of Venus is largely the result of volcanic activity. Over the millennia, there have been extensive volcanic eruptions that pumped carbon dioxide into the atmosphere. The lack of bodies of water on Venus meant the built up carbon dioxide in the atmosphere didn’t get absorbed. In addition to this, the lack of a magnetic field meant the solar wind – the pressure from the Sun – drove away the lighter elements leaving behind the thick, carbon dioxide rich atmosphere we see today. But the volcanoes that drove the atmospheric changes are thought to have been extinct for a long time. 

It’s not just the Venera probes that have been exploring Venus. In 1980, the Magellan spacecraft was launched by NASA to map the surface of the hottest planet in the Solar System. On arrival, it was put into a polar orbit and used radar to penetrate the thick clouds. Back in 2023, a study of some of the Magellan images from the synthetic aperture radar showed changes to a vent near the summit of Maat Mons. It was the first direct evidence of an eruption on the surface of Venus and changes in the lava flows. 

The surface of Venus captured by a Soviet Venera probe. Credit: Russian Academy of Sciences / Ted Stryk

In the latest study that was published in Nature Astronomy, more data from the synthetic aperture radar was studied. The team focussed on Sif Mons and Niobe Planitia and the data that had been collected from both areas in 1990 and again in 1992. The data revealed stronger radar returns in the later set of data suggesting new rock formations from volcanic activity. The team did consider it may have been caused by some other phenomena such as sand dunes or atmospheric effects but altimeter data confirmed the presence of new solidified lava. 

The team were able to use lava flows on Earth as a comparison to help understand the new flows on Venus. They estimated that the new flows are between 3 and 20 metres deep. They could go a step further though and estimated that the eruption at Sif Mons produced about 30 square kilometres of rock which would be enough to fill over 36,000 swimming pools.  The eruption at Niobe Planitia produced even more with an estimated 45 square kilometres of rock..

Studying volcanic activity on Venus helps to understand not just the geological processes but also helps to understand the structure of the interior too. This can help inform the likelihood of habitability for future explorers. None of which would have been possible without the recent volcanic activity to help us probe further the secrets of Venus.

Source: Ongoing Venus Volcanic Activity Discovered With NASA’s Magellan Data

The post Volcanoes Were Erupting on Venus in the 1990s appeared first on Universe Today.

We’re fortunate to live in these times. Multiple space telescopes feed us a rich stream of astounding images that never seems to end. Each one is a portrait of some part of nature’s glory, enriched by the science behind it all. All we have to do is revel in the wonder.

The ESA’s Euclid space telescope is the latest one to enrich our inboxes. It was launched on July 1st, 2023, and delivered its first images in November of that year. Now, we have five new images from Euclid, as well as the first science results from the wide-angle space telescope.

“They give just a hint of what Euclid can do.”

Valeria Pettorino, ESA’s Euclid Project Scientist.

The images demonstrate the telescope’s power and its ability to address some of the deepest questions we have about the Universe. They are also impressive because of their visual richness and because they took only 24 hours of the telescope’s expected six years of observing time.

“Euclid is a unique, ground-breaking mission, and these are the first datasets to be made public – it’s an important milestone,” says Valeria Pettorino, ESA’s Euclid Project Scientist. “The images and associated science findings are impressively diverse in terms of the objects and distances observed. They include a variety of science applications, and yet represent a mere 24 hours of observations. They give just a hint of what Euclid can do. We are looking forward to six more years of data to come!”

The leading image is the most stunning and perhaps the most relatable. It shows Messier 78, aka NGC 2068. It’s a reflection nebula and star-forming region contained in the vast Orion B molecular cloud complex. Euclid used its infrared capabilities to see through the dust that shrouds the star-formation region. It’s given us our most detailed look at the filaments of gas and dust that give the region its ghostly appearance.

Euclid can detect objects that are just a few times more massive than Jupiter, an impressive feat. In its M78 image, it found over 300,000 objects in that mass range.

This zoomed-in portion of Euclid’s M78 image shows the depth the telescope’s images deliver. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE CC BY-SA 3.0 IGO

One of Euclid’s objectives is to study dark matter and how it’s distributed in the Universe. It uses gravitational lensing to probe dark matter, and its image of the Abell 2390 galaxy cluster exhibits the tell-tale curved arcs of light coming from distant background objects created by gravitational lensing. The image also shows more than 50,000 galaxies.

Euclid’s image of the Abell 2390 cluster of galaxies contains over 50,000 galaxies. It also shows the intracluster light that comes from individual stars torn from their galaxies and sitting in intergalactic space. These stars can help astrophysicists determine where dark matter is. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi.
LICENCE: CC BY-SA 3.0 IGO

Most of the stars currently forming in the Universe are forming in spiral galaxies. Euclid captured this image of NGC 6744 as an archetype of that galaxy type. The telescope’s wide-angle lens and depth of field capture the entire galaxy and also small details. It shows lanes of dust that emerge as spurs on the spiral arms.

With this image, astronomers can map individual stars and the gas that feeds their formation. They can also identify globular clusters and new dwarf galaxies. Euclid already found one new dwarf galaxy astronomers have never seen before, which is impressive for a galaxy that’s already been studied so intently.

Euclid’s complete image of NGC 6744 is on the left, and a zoomed-in portion is on the right. NGC 6744 is one of the largest spiral galaxies outside our region of space. The telescope’s detailed image will let astronomers count and map individual stars and the gas that feeds star formation. Star formation is how galaxies evolve, so studying NGC 6744’s star formation activity feeds into a greater understanding of galaxy evolution. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: CC BY-SA 3.0 IGO

Euclid also imaged another galaxy cluster, Abell 2764. This cluster contains hundreds of galaxies within a halo of dark matter. Euclid’s impressive wide-field view comes into play in this image. Not only does it show Abell 2764 in the image’s upper right, but it also shows other clusters that are even more distant, multiple background galaxies, and interacting galaxies with their streams of stars.

In this image, Euclid captured galaxy cluster Abell 2764 and the wider region surrounding it. Abell 2764 is in the upper right corner. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi LICENCE CC BY-SA 3.0 IGO

The image highlights one of Euclid’s other capabilities. The foreground star is in our own galaxy, and when viewed with a telescope, its diffuse light creates a halo that obscures distant objects behind it. Euclid was built to minimize that diffuse halo effect. The disturbance from the star’s diffuse light is minimal, meaning Euclid can see distant background objects near the star’s line of sight.

This pair of zoomed-in images of Abell 2764 shows Euclid’s power. On the left is the foreground star. These stars can create halos of diffuse light that obscure other objects, but Euclid is built to minimize the effect. On the right is a zoom-in of Abell 2764 itself, with multitudes of background galaxies. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: CC BY-SA 3.0 IGO

The final of the five new images is of galaxies in the Dorado Group. Euclid’s image shows signs of galaxies merging. The Dorado Group is a relatively young group, and many of its member galaxies are still forming stars. The image helps astronomers study how galaxies form and evolve inside halos of dark matter.

The Dorado Group is one of the richest galaxy groups in the southern hemisphere. Euclid’s wide and deep images give astronomers their best look at it. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: ESA Standard Licence

A zoomed-in image shows more detail of the main pair of galaxies in the image. Euclid’s unique large field-of-view and high spatial resolution means that for the first time, astronomers can use the same instrument and observations to deeply study tiny objects the size of star clusters, intermediate objects like the central regions of galaxies, and larger features like tidal tails in one large region of the sky.

“The beauty of Euclid is that it covers large regions of the sky in great detail and depth, and can capture a wide range of different objects all in the same image – from faint to bright, from distant to nearby, from the most massive of galaxy clusters to small planets.”

ESA Director of Science, Prof. Carole Mundell

Prior to Euclid, astronomers had to use small chunks of data to painstakingly catalogue globular clusters around galaxies. But Euclid’s wide images capture far more data in a single image, simplifying the task. Globular clusters provide important clues to how galaxies evolve over time.

This zoom-in shows a pair of interacting galaxies in the Dorado Group. Tidal tails of stars are visible as wispy streams near the right and bottom right of the right-side galaxy. Image Credit: ESA/Euclid/Euclid Consortium/NASA, image processing by J.-C. Cuillandre (CEA Paris-Saclay), G. Anselmi. LICENCE: ESA Standard Licence

Euclid’s mission is only starting. The telescope’s images so far have no equivalent, and there’s much more to come. Euclid hasn’t even begun its main survey yet. That survey will comprise both a wide survey covering about 15,000 square degrees of the sky and a deep survey covering about 50 square degrees.

“It’s no exaggeration to say that the results we’re seeing from Euclid are unprecedented,” says ESA Director of Science, Prof. Carole Mundell. “Euclid’s first images, published in November, clearly illustrated the telescope’s vast potential to explore the dark Universe, and this second batch is no different.”

“The beauty of Euclid is that it covers large regions of the sky in great detail and depth, and can capture a wide range of different objects all in the same image – from faint to bright, from distant to nearby, from the most massive of galaxy clusters to small planets,” said Mundell. “We get both a very detailed and very wide view all at once. This amazing versatility has resulted in numerous new science results that, when combined with the results from Euclid’s surveying over the coming years, will significantly alter our understanding of the Universe.”

The scientific papers released with these images are available here.

The post Enjoy Five New Images from the Euclid Mission appeared first on Universe Today.

Normally you don’t want dust to get into your spacecraft. That was certainly true for the InSight mission to Mars, until it died. Now, however, it’s acting as a dust collector, and Mars Reconnaissance Orbiter (MRO) scientists couldn’t be happier.

The High Resolution Imaging Science Experiment (HiRISE) onboard MRO monitors and images the surface. In particular, it has been imaging landing sites on Mars to track dust accumulation on the surface. The idea is to see how quickly the landers and their nearby environments get covered. It doesn’t just focus on landing sites, though. It also checks places like impact craters to track surface changes in and around those regions. As you can see from its latest image above, taken on April 1st, 2024, it’s getting tough to spot the InSIGHT lander thanks to ever-growing accumulations of dust.

Monitoring Surface Changes on Mars

HiRISE has been checking in on the InSIGHT lander ever since it first deployed on Mars. Early images show the hardware in fairly good detail right after landing. Then, over time, as Martian winds take their toll, it’s obvious the spacecraft is getting coated in dust. That’s also true of other spacecraft that HiRISE images from time to time.

The best image of the InSight lander taken by HiRISE in 2019. HiRISE scientists were looking for dust devil tracks and other changes in the surface due to dust. Credit: NASA/JPL-Caltech/UArizona

Why care about dust? Although we know a great deal about Mars, there’s still a lot to figure out. Wind deposition of dust is part of the so-called aeolian processes that alter the Martian surface appearance. They’re named after the Greek wind god Aeolus. Dust storms are certainly visible on Mars from Earth, but we can’t really “see” their deposits easily without getting close to (or on) the planet. Other activities, such as dust devils, also redistribute dust around the planet. All this activity creates wind streaks, sand, and dust deposits, and covers up spacecraft on the surface.

The study of the aeolian process is one of the HiRISE instrument’s major science themes. There’s not much water action to change the surface. Nor is there any Martian volcanic activity to muck up the landscape. Impact craters do tear up the surface, but they aren’t frequent. That leaves aeolian activity as a major player in Mars surface changes. Image after image shows dunes, ripples, wind streaks, dust devil tracks, and other features created by the winds. The HiRISE imaging project gives a “wide-angle” view of aeolian effects on the Red Planet and how its various surface units change over time.

InSight’s Future on Mars

The InSight lander performed almost flawlessly during its four years in operation on Mars. Although one of its instruments, the “mole” had some difficulties performing its digging action, the mission as a whole was quite successful. The seismograph monitored Marsquakes throughout the mission, which gives details about the Martian interior. It also differentiated between quakes from Mars’s interior and those caused by impacts. The spacecraft other instruments sampled the remnants of the weak magnetic field and monitored the Martian weather.

The InSight lander not only measured seismic motions on Mars, but also sampled the atmosphere and listened to its winds. Courtesy: NASA/JPL.

As increasing levels of dust covered InSight’s solar panels, mission scientists had to power down many of its systems. The seismometer was the last one to be shut off. The spacecraft was officially considered “dead” after mission controllers didn’t hear from it after two attempts at communication. The last time anybody heard from it was December 15, 2022.

These days, although the instruments are silent and the solar panels are dead, the spacecraft is passively and rapidly accumulating dust. That gives scientists a chance to understand just how the surface changes thanks to aeolian activity.

For More Information

Revisiting InSight
Aeolian Themes for HiRISE
Winds of Mars
InSight Mission Ends

The post Mars InSight Has One Last Job: Getting Swallowed by Dust on the Red Planet appeared first on Universe Today.

Nothing lasts forever, including black holes. Over immensely long periods of time, they evaporate, as will other large objects in the Universe. This is because of Hawking Radiation, named after Stephen Hawking, who developed the idea in the 1970s.

The problem is Hawking Radiation has never been reliably observed.

A trio of European researchers think they’ve found a way to see Hawking Radiation. Their work is in a paper titled “Measuring Hawking Radiation from Black Hole Morsels in Astrophysical Black Hole Mergers.”

Black hole mergers were predicted long ago but never observed. Theory showed that these mergers should release powerful gravitational waves. Finally, in 2015, the LIGO observatory detected the first merger. Now, scientists have detected many of them.

In their brief research letter, the researchers say that these mergers are a window into Hawking Radiation (HR.) When black holes merge, they may create so-called “morsel” black holes the size of asteroids that are ejected into space. Their small size should make their HR detectable.

The HR coming from these small BHs produces gamma rays with a particular “fingerprint” of high-energy photons.

“In this letter, we explore the observational consequences of the production of a large number of small BH morsels during a catastrophic event such as the merger of two astrophysical BHs,” the authors explain. “As we shall show, the Hawking radiation stemming from these BH morsels gives rise to gamma-ray bursts (GRBs) possessing a distinctive fingerprint.”

When black hole morsels evaporate, they emit particles in a spherically symmetrical pattern. As long as the larger merged BH is not blocking their view, the HR particles should reach us. The photon energy from the bursts exceeds the trillion-electron volt (TeV) scale.

The researchers say that the energy level of the gamma-ray bursts from these morsel holes is detectable by atmospheric Cherenkov telescopes like the High-Altitude Water Cherenkov (HAWC) Gamma-ray observatory. HAWC observes photons in a range from 100 GeV to 100 TeV.

HAWC is at an altitude of 4100 meters ((2.5 miles) in Mexico. It’s one of several facilities that can detect energetic photons from morsel black holes. Image Credit: By Jordanagoodman – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=35122613

Many questions remain. The authors say that these morsel BHs will emit the most energy close to their time of evaporation. But when morsel BHs are emitted in the intense gravitational environment of a BH merger, their Hawking Radiation may be affected. The same is true if the morsels are emitted at relativistic velocities. Both of those factors could alter their spectra before they reach our detectors.

There are points in the Standard Model of Particle Physics where things break down due to our lack of understanding. The authors point out that some new physics not observed before could also distort the spectra from morsel black holes, making them tricky to observe.

There’s another really interesting aspect to these asteroid-size morsel black holes. Since the physics in the very early Universe were different, it’s possible they were created then. If they were, and if they haven’t evaporated by now, they could constitute dark matter.

“The observation of Hawking radiation from BH morsels, therefore, could enlighten us not only about the production of such morsels but also about particle physics at energies beyond the reach of current and future collider experiments, carrying imprints from new physics based on supersymmetry, composite dynamics, or extra dimensions, to name a few,” the authors write.

The post Merging Black Holes Could Give Astronomers a Way to Detect Hawking Radiation appeared first on Universe Today.

How can sunlight reflecting off SpaceX’s Starlink satellites interfere with ground-based operations? This is what a recently submitted study hopes to address as a pair of researchers investigate how Starlink satellites appear brighter—which the researchers also refer to as flaring—to observers on Earth when the Sun is at certain angles, along with discussing past incidents of how this brightness has influenced aerial operations on Earth, as well. This study holds the potential to help spacecraft manufacturers design and develop specific methods to prevent increased brightness levels, which would help alleviate confusion for observers on Earth regarding the source of the brightness and the objects in question.

Here, Universe Today discusses this research with Anthony Mallama of the IAU – Centre for the Protection of Dark and Quiet Skies from Satellite Constellation Interference regarding the motivation behind the study, significant results, potential follow-up studies, importance of studying Starlink satellite brightness, and implications for managing satellite constellations in the future. So, what was the motivation behind this study?

“I study the brightness of Starlink satellites under all circumstances,” Mallama tells Universe Today. “That includes their operational phase at 550 km [342 mi] altitude, when they are rising from the initial orbit around 300 km [186 mi] to operation height, ordinary flares which occur frequently but have small amplitudes and these extreme flares.”

For the study, the researchers conducted a geometrical analysis of the brightness of Starlink satellites based on the Sun’s location and angle in the sky. This comes despite SpaceX taking steps to mitigate reflectivity off Starlink satellites, which only decreases reflectivity when the satellites are directly overhead. The study also discussed how reflectivity from Starlink satellites has affected aerial operations, specifically with commercial airline pilots. Therefore, what were the most significant results from this study?

Mallama tells Universe Today, “This study demonstrated that Starlinks can be exceedingly bright under certain conditions. In one instance they were reported as Unidentified Aerial Phenomenon (UAP) by pilots on two commercial aircraft.”

Regarding potential follow-up studies, Mallama tells Universe Today, “I am characterizing the brightness of other satellite constellations including Amazon’s Kuiper, AST SpaceMobile’s BlueWalker/BlueBirds and Planet’s Pelicans.”

The study mentions how the UAP incidents occurred in 2022 and was recently discussed in Buettner et al (2024) with the pilots’ reporting brightness magnitudes (also called stellar magnitude or apparent magnitude) of -4 to -5. For context, a stellar magnitude of -5 is equivalent to the planet Venus at its brightest, which is known for being observed before sunrise or after sunset periodically throughout the year. The apparent magnitude scale ranges from -30 to 30 with higher numbers corresponding to decreasing brightness.

Buettner et al (2024) was recently presented at the 4th IAA Conference on Space Situational Awareness (ICSSA). That paper discussed how the incident occurred on August 10, 2022, and was observed by five pilots aboard two separate commercial airline flights over the Pacific Ocean, which resulted in two photographs obtained by the pilot’s cell phones. After analyzing a series of simulations and additional data, the researchers determined these UAPs were Starlink satellites launched earlier that day, which was designated as Starlink Group 4-26. Given this incident, what is the importance of studying Starlink brightness/flaring?

Mallama tells Universe Today, “The importance of studying Starlink brightness is that the satellites interfere with astronomical research if they are brighter than magnitude 7. Furthermore, casual sky watchers, such as amateur astronomers and naturalists, are distracted by those brighter than magnitude 6 because they are visible to the unaided eye.”

This study comes as SpaceX’s Starlink constellation continues to grow on a regular basis, with the number of current Starlink satellites in orbit have reached more than 5,600 with almost 6,000 having been launched by SpaceX as of this writing. As noted by both the study and Mallama, sunlight reflectivity off Starlink satellites causes issues with both aerial operations on Earth and astronomical observing, with Mallama also conducting research on satellite constellation brightness for Amazon, AST SpaceMobile, and Planet Labs. Therefore, with the number of satellites in orbit rapidly increasing due to constellations, what implications could this study have on managing satellite constellations in the future?

Mallama tells Universe Today, “One approach to reducing satellite brightness is to reflect sunlight into space rather than allowing it to scatter diffusively toward observers on the ground. That works very well most of the time. However, there are certain Sun-satellite-observer geometries where it fails and observers see a mirror-like reflection of the Sun.” Mallam published a 2023 article with Sky & Telescope discussing how SpaceX’s second-generation of Starlink satellites are fainter than their predecessors.

This diagram and artist illustration demonstrates how sunlight reflects off a Starlink version 1.5 satellite, and was discussed in a 2023 article authored by Anthony Mallama and published in Sky & Telescope. (Credit: SpaceX)

Mallama credits his co-author, Richard Cole, as playing a “crucial role” in this study, noting how Cole “predicted the extreme flares based on his numerical model of Starlink satellite brightness.”

How will sunlight reflectivity off Starlink satellites influence ground operations in the coming years and decades, and what steps can be taken to mitigate this activity? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Starlinks Can Produce Surprisingly Bright Flares to Pilots appeared first on Universe Today.

It’s been a momentous May for skywatchers around the world. First the big auroral event of May 10-11, next a flaming space rock entering over Spain and Portugal. The inbound object was captured by ground-based cameras and the MeteoSat Third Generation Imager in geostationary orbit.

The incoming meteor dazzled viewers across both countries as it sped across the skies at 160,000 km/hour. Of course, social media came alive with speculation about what was burning up in the atmosphere. Most people thought it was a piece of space rock from an asteroid. European Space Agency members of the Planetary Defence Office immediately began analyzing images and data to figure out the composition of the impactor. Now it seems more likely the chunk of space debris came from a comet. They used other data about the energy released as the fragment flew through the atmosphere to determine the size of the object. It was likely about 1 meter across with a mass of between 500 to 1,000 kg.

On 18 May, the meteor burned up in the night sky over Spain and Portugal – as seen by the fireball camera in Cáceres, Spain, operated by ESA’s Planetary Defence Office

This is pretty small, which makes it hard to spot on the way in. Also, the object approached from the direction of the sky crowded with stars, making it doubly difficult to see as it spun into our planet’s atmosphere. It explains why planetary defense telescopes or observers didn’t detect the meteor.

The Meteor’s Appearance

To most observers, the meteor over Portugal and Spain looked blue-green and very bright. Those colors are created as various elements in the meteor get heated up by friction with our atmosphere. That vaporizes them and we see the “fiery” aspect light up the sky. If it was a piece of a comet, then the colors also indicate the materials it contained. Most comets contain water, carbon dioxide, ammonia, and methane ice. Other comet “stuff” consists of silica dust, carbon, various metals, and organic molecules. The metals, in particular, could show spectacular colors as they heat up and vaporize.

It’s not known which comet supplied the chunk that broke up and vaporized that night. Earth’s orbit crosses the orbit of several different comets. As they travel through space, particularly as they get close to the Sun, comets shed pieces of themselves. That cometary debris stays in the original orbit around the Sun. Occasionally, Earth’s orbit intersects that cometary path. Its particles particles eventually end up in our atmosphere. The best-known path creates the Orionid Meteor Shower and we can thank Comet Halley for that show from late September to mid-November.

Surveys to Detect an Incoming Space Rock

As planetary scientists learn more about the near-Earth environment and its population of asteroids and other space debris, they’ve formed observation groups within NASA and ESA. There’s a network of ground-based observers and facilities that watch the sky each night, looking for incoming impactors. Most of the time, their search is limited to objects larger than the Portugal/Spain object. In addition, satellites such as MeteoSat can pick up these intruders. MeteoSat was launched by ESA to monitor weather conditions and detect lightning strikes. The instrument has four cameras covering Europe, Africa, the Middle East, and parts of South America. Each can capture up to a thousand images per second, allowing the satellite to monitor lightning continuously from space.

ESA’s Planetary Defence Office is in charge of monitoring the positions and approaches of near-Earth objects that could pose a threat to any portion of our planet. It does regular observing campaigns to search for bits of asteroids and comets. NASA operates the Center for Near Earth Object Studies (CNEOS) to do similar searches for possibly dangerous rocks. The Near-Earth objects it’s most concerned about are asteroids and comets with orbits that bring them to within 195 million kilometers of the Sun. Their orbits can move through our planet’s neighborhood. Most of these small bodies are asteroids as small as a few meters wide to nearly 40 kilometers across.

Artist’s concept of the path that a space rock can take that might bring it near Earth. Planetary defense facilities around the planet try to track these objects and warn of their close approach whenever possible. Courtesy: ESA – P.Carril.

The office uses data from observatories around the world—both professional and amateur. Much of this data comes from larger facilities, including Pan-STARRS, the Catalina Sky Survey, and NASA’s NEOWISE mission. In addition, there’s a significant program of planetary radar measurements that contribute data to the NEO observations effort. All of these skywatching campaigns contribute to increased awareness and predictions of near-Earth objects that could pose a threat to our planet.

For More Information

Fireball Witnessed by Weather Satellite

Asteroid Watch

ESA Planetary Defence Office

The post A Weather Satellite Watched a Space Rock Burn Up Above Spain and Portugal appeared first on Universe Today.

One of the main objectives of the James Webb Space Telescope (JWST) is to study the early Universe by using its powerful infrared optics to spot the first galaxies while they were still forming. Using Webb data, a team led by the Cosmic Dawn Center in Denmark pinpointed three galaxies that appear to have been actively forming just 400 to 600 million years after the Big Bang. This places them within the Era of Reionization, when the Universe was permeated by opaque clouds of neutral hydrogen that were slowly heated and ionized by the first stars and galaxies.

This process caused the Universe to become transparent roughly 1 billion years after the Big Bang and (therefore) visible to astronomers today. When the team consulted the data obtained by Webb, they observed that these galaxies were surrounded by an unusual amount of dense gas composed almost entirely of hydrogen and helium, which likely became fuel for further galactic growth. These findings already reveal valuable information about the formation of early galaxies and show how Webb is exceeding its mission objectives.

The research was led by Kasper E. Heintz, a NASA Hubble Fellow and an assistant professor of astrophysics, and his colleagues at the Cosmic Dawn Center (DAWN) at the Niels Bohr Institute. They were joined by researchers from ETH Zurich, the MIT Kavli Institute for Astrophysics and Space Research, the Space Telescope Science Institute (STScI), the Association of Universities for Research in Astronomy (AURA), the European Space Agency (ESA), the NSF’s National Optical-Infrared Astronomy Research Laboratory (NOIRLab), and multiple universities.

Illustration showing the process of Cosmic Reionization, divided into four periods. Credit: NASA

According to models of galaxy formation, the first galaxies are believed to have resulted from the infall of neutral, pristine gas onto the first protogalactic halos. However, the abundance of neutral atomic hydrogen in galaxies has remained unknown due to the difficulty of observing the earliest cosmological periods. “These galaxies are like sparkling islands in a sea of otherwise neutral, opaque gas,” Heintz explained in a NASA press release. “Without Webb, we would not be able to observe these very early galaxies, let alone learn so much about their formation.”

Since the galaxies appeared as little more than red blobs in the Webb images, the team also relied on data obtained by Webb‘s Near Infrared Camera (NIRCam) through the Cosmic Evolution Early Release Science (CEERS) Survey and shared through the Early Release Science (ERS) program. The spectra revealed that light from these galaxies is absorbed by large amounts of neutral hydrogen gas. They then matched the Webb data to models of star formation, which revealed that these galaxies are primarily populated by young stars. Said co-author Darach Watson, a professor at DAWN:

“The gas must be very widespread and cover a very large fraction of the galaxy. This suggests that we are seeing the assembly of neutral hydrogen gas into galaxies. That gas will go on to cool, clump, and form new stars. The fact that we are seeing large gas reservoirs also suggests that the galaxies have not had enough time to form most of their stars yet.”

“We’re moving away from a picture of galaxies as isolated ecosystems,” added Simone Nielsen, a co-author and PhD student at DAWN. “At this stage in the history of the universe, galaxies are all intimately connected to the intergalactic medium with its filaments and structures of pristine gas.”

The timeline from the Big Bang on the right towards the present on the left. In the middle is the Reionization Period where the initial bubbles caused the Cosmic Dawn. Credit: NASA SVS

These results illustrate what is now possible for astronomers, thanks to next-generation telescopes like Webb. Of course, many unanswered questions remain, not the least of which has to do with the distribution of the cold gas in these early galaxies. For instance, how much is located near the center of galaxies versus their outskirts? Also, astronomers are still unsure if this gas is pristine or already populated by heavier elements. As Heintz indicated, “The next step is to build large statistical samples of galaxies and quantify the prevalence and prominence of their features in detail.”

Further Reading: NASA, Science

The post Galaxies in the Early Universe Preferred their Food Cold appeared first on Universe Today.

Sometimes, astronomers get lucky and catch an event they can watch to see how the properties of some of the most massive objects in the universe evolve. That happened in February 2020, when a team of international astronomers led by Dheeraj (DJ) Pasham at MIT found one particular kind of exciting event that helped them track the speed at which a supermassive black hole was spinning for the first time.

Dr. Pasham found AT2020ocn, a bright flash captured by the Zwicky Transient Facility at Palomar Observatory. He thought it might signify a tidal disruption event (TDE). In these extreme events, a black hole rips apart a star. Part of the star’s remnants are flung from the black hole, but part falls into the accretion disk. And how they fall could hold the key to understanding how a black hole is spinning.

How that disk accretes is attributable to a cosmological theory called Lense-Thirring precession, which shows how space-time is warped by powerful gravitational fields—like those around black holes. Lense-Thirring theory predicts that an accretion disk formed after a TDE would “wobble” soon after the event before settling down into a more standard pattern of matter orbiting a black hole. The key would be to catch a TDE event very early after it happened and then watch the resulting “wobbling” over as long of a time span as possible.

Fraser discusses measuring the spin of a black hole.

So catching AT2020ocn was just the first step—then the authors had to monitor it—preferably for months. To do so, they recruited the Neutron Star Interior Composition ExploreR (NICER), an X-ray telescope attached to the ISS. NICER watched the galaxy containing AT2020ocn for 200 days immediately following the bright flash caught by Zwicky. 

They began to notice a pattern. Every 15 days, the amount of X-rays emitted around the black hole peaked sharply, indicating the potential “wobble” they were looking for. Plugging that frequency into equations for the Lense-Thirring theory, along with estimates of the star’s mass and the black hole’s mass, they determined the black hole was spinning at 25% of the speed of light—which is actually relatively slow for a black hole.

A black hole’s rotational speed can increase or decrease depending on its local environment. As it absorbs more material, typically in the form of matter from its accretion disk falling into it, its rotational speed increases. On the other hand, if it collides with another black hole, the overall rotational speed could decrease, as the two black holes’ spins could be opposite. That appears to be what has happened with the black hole that caused the AT2020ocn TDE, given its relatively slow speed compared to other black holes.

Black holes typically spin exceptionally fast, as Fraser discusses in this video.

The findings of this work were recently published in a paper in Nature. They also potentially lay the groundwork for calculating the spin of other supermassive black holes in the galaxy. Dr Pasham believes astronomers could calculate the spins of hundreds of black holes, opening up insights into their formation and life cycle.

But to do that, they will still need a lot of luck. TDEs are relatively rare events, and even when they do happen, there are obvious resource constraints on telescope time. The Vera Rubin Observatory might help, as it will monitor large chunks of the sky, but it’s not scheduled to come online until mid-next year. Until then, those interested in tracking black hole spins might have to rely on serendipity to find a rare event and have the telescope time to monitor it.

Learn More:
MIT – Using wobbling stellar material, astronomers measure the spin of a supermassive black hole for the first time
Pasham et al. – Lense–Thirring precession after a supermassive black hole disrupts a star
UT – Black Holes are Firing Beams of Particles, Changing Targets Over Time
UT – The Milky Way’s Black Hole is Spinning as Fast as it Can

Lead Image:
Artist’s depiction of how the accretion disk around a black hole could wobble in frequency with its spin, and how that wobble might be captured by a sensor near Earth.
Credits: Michal Zajacek & Dheeraj Pasham

The post A New Way to Measure the Rotation of Black Holes appeared first on Universe Today.

NASA is actively working to return surface samples from Mars in the next few years, which they hope will help us better understand whether ancient life once existed on the Red Planet’s surface billions of years ago. But what about atmospheric samples? Could these provide scientists with better information pertaining to the history of Mars? This is what a recent study presented at the 55th Lunar and Planetary Science Conference hopes to address as a team of international researchers investigated the significance of returning atmospheric samples from Mars and how these could teach us about the formation and evolution of the Red Planet.

Here, Universe Today discusses this research with the study’s lead author, Dr. Edward Young, who is a professor in the Department of Earth, Planetary, and Space Sciences at UCLA, and study co-author, Dr. Timothy Swindle, who is a Professor Emeritus in the Lunar & Planetary Laboratory at the University of Arizona, regarding the motivation behind the study, how atmospheric samples would be obtained, current or proposed missions, follow-up studies, and whether they think life ever existed on the Red Planet. Therefore, what was the motivation for the study?

Dr. Young tells Universe Today, “We learn a lot about the origin of a planet from its atmosphere as well as its rocks. In particular, isotope ratios of certain elements can constrain the processes leading to the formation of the planet.”

Credit: European Space Agency

Dr. Swindle follows this with, “There are two basic types of motivation. One is that we’re planning on bringing all these rock samples, and we’re going to be interested in knowing how they’ve interacted with the atmosphere, but we can’t figure that out without knowing the composition of the atmosphere in detail. So, we need an atmospheric sample to know what the rocks might have been exchanging elements and isotopes with. But we’d also like to have a sample of the Martian atmosphere to answer some basic questions about processes that have occurred, or are occurring, on Mars. For example, Martian meteorites contain trapped atmospheric noble gases, like krypton and xenon. But it appears that there are at least two different “atmospheric” components in those meteorites.”

For the study, the researchers proposed several benefits of returning a Mars atmospheric sample to Earth, including atmospheric samples being among the NASA Perseverance (Percy) rover sample tubes, gaining insight into potential solar gar within the Martian interior, evolutionary trends in atmospheric compositions, nitrogen cycling, and sources of methane on Mars. For the Percy atmospheric sample, also known as Sample No.1 “Roubion”, the study notes how this sample was obtained after Percy tried to collect a rock core sample but ended up collecting atmospheric gases instead. Additionally, the study proposes the lack of leakage the sample tube will experience while awaiting its return to Earth and the gases present within the sample are ideal for analysis once returned to Earth, as well. But aside from the Percy rover sample, how else could a Martian atmosphere sample be obtained?

“At least two other ideas for collecting a sample of Martian atmosphere have been suggested,” Dr. Swindle tells Universe Today. “One is to fly a spacecraft through the Martian atmosphere, collect a sample as it goes through, then return it to Earth. The other is to have a sample return “cannister” (it doesn’t have to be any bigger than a Perseverance tube) that has valves and a (Martian) air compressor. You could land it on the surface of Mars, open the valve to the atmosphere, turn on the compressor, and get a sample that has hundreds or thousands of times as much Martian atmosphere as a volume that is just sealed without compression, as Perseverance has done, and hopefully will do again.”

Dr. Swindle and Dr. Young both mention the Sample Collection for Investigation of Mars (SCIM) mission, which was proposed in 2002 by a team of NASA and academic researchers with the goal of collecting atmospheric samples at an altitude of 40 kilometers (25 miles) above the Martian surface and return them to Earth for further analysis. While SCIM was selected as a semi-finalist for the 2007 Mars Scout Program, it was unfortunately not selected for further development, and both Dr. Young and Dr. Swindle tell Universe Today there are currently no atmospheric sample missions being planned aside from the Percy rover sample. Therefore, what follow-up studies from this research are currently underway or being planned?

Dr. Swindle and Dr. Young both mention how efforts are being made to collect small quantities of atmospheric gas due to the small size of the sample tubes, with Dr. Swindle telling Universe Today, “A big set of questions right now is how good a sealed Perseverance tube would be at containing an atmospheric sample. How good is the seal? Might the tube spring a leak on a hard landing? Would some molecules in the Martian atmosphere stick to the coatings of the tubes? There’s been some activity on all of these questions, and so far, the answers have all been good – it looks like those Perseverance tubes may do well, even though they weren’t really designed with atmospheric sampling in mind.”

As noted, the purpose of obtaining and returning an atmospheric sample from Mars could help scientists better understand the formation and evolution of the Red Planet. While present-day Mars is a very cold and dry world with an atmosphere that is a fraction of the Earth’s atmosphere, with liquid water being unable to exist on the surface, along with no active volcanism, as well. However, significant evidence obtained from landers, rovers, and orbiters over the last several decades point to a much different Mars billions of years ago after it first formed. This included an active interior that produced a magnetic field that shielded the surface from harmful solar and cosmic radiation, a much thicker atmosphere being replenished from active volcanism, and flowing liquid water, all of which potentially led to the existence of some forms of life on the surface.

However, given Mars’ small size (half of Earth), this means its internal heat cooled off much faster (possibly over millions of years), resulting in volcanism becoming inactive and the dissipation of the magnetic field the interior activity was driving, the latter of which led to harmful solar and cosmic radiation stripping the atmosphere, with the surface liquid water evaporating to space along with it. Therefore, do Dr. Young and Dr. Swindle believe life ever existed on Mars, and will we ever find it?

Dr. Young tells Universe Today, “I really don’t know.  I think microbial life sometime in the past, or even now, is a reasonable hypothesis but we don’t have enough information.”

Dr. Swindle also echoes his uncertainty whether life ever existed on Mars, but elaborates by telling Universe Today, “If there hasn’t, why did life start so early on Earth, but didn’t start on Mars, which had a similar climate at the time. If there has been, how similar is it to life on Earth? Since Earth and Mars are always exchanging rocks because of impacts, is life on Earth related to life on Mars? If it has existed, it will be tough to find. But an atmospheric sample could help. For instance, there seems to be methane in the Martian atmosphere. Most, but not all, of the methane in Earth’s atmosphere is biological, and analyzing the relative ratios of the isotopes of carbon or hydrogen is one of the best ways to figure that out.”

When will we obtain an atmospheric sample of Mars and what will it teach us about the formation and evolution of the Red Planet in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Could Martian atmospheric samples teach us more about the Red Planet than surface samples? appeared first on Universe Today.

Black holes seem to provide endless fascination to astronomers. This is at least partly due to the extreme physics that takes place in and around them, but sometimes, it might harken back to cultural touchpoints that made them interested in astronomy in the first place. That seems to be the case for the authors of a new paper on the movement of jets coming out of black holes. Dubbing them “Death Star” black holes, researchers used data from the Very Long Baseline Array (VLBA) and the Chandra X-ray Observatory to look at where these black holes fired jets of superheated particles. And over time the found they did something the fiction Death Star could also do – move.

The black holes at the center of the study were supermassive ones at the centers of galaxies. Importantly, they were all surrounded by hot gases that were visible to Chandra’s X-ray sensors. The jets themselves were clearly visible in the data, but there was other important information hiding in it—namely, pockets free from gas, which had been pushed away by the jets.

Each black hole has particle jets in two opposing directions. As those jets push away gas and dust, they open up a pocket in space surrounding the black hole. These are visible in the X-ray data due to a lack of signal from those regions. The researchers hypothesized that the jets should align with the pockets of free space they create.

Black holes have been known to spin for a while – as Fraser discusses.

However, they found that, in at least 6 of the 16 black holes they were studying, the beams had completely changed direction such that the pockets of missing gas no longer aligned with the jets currently emitted from the black hole. In some cases, these changes added up to a 90-degree shift in the direction the jets were facing. What’s even more impressive, they seemed to move on a relatively small time scale, with estimates ranging from 1 to 10 million years. That is a blink of an eye for a black hole over 10 billion years old.

So why is this important? Cosmologists theorize that these disruptive jets put an upper limit on the number of stars that form in the host galaxy of the black holes. They don’t let the gas and dust surrounding them cool down enough to start to form stars and rocky planets. So, while it isn’t clear if the jets of particles themselves are roasting any formed planets like the actual Death Star, it is clear that moving the jets around would cause an even more massive disruption in the star-forming process. In theory, this would mean that galaxies containing these moving jets would have fewer stars, but that is a study for another paper.

Understanding exactly why this is happening might also need to be researched in another paper, but the authors have a few theories. Matter orbiting around the black hole and falling into it could cause the black hole to rotate, causing the jets it emits to move with it. 

How a black hole forms could hold the key to understanding why its jets move over time. Fraser discusses how that happens.

Another explanation is that the gas is moving around the galaxy without being impacted by the beams. In essence, the “cavities” of no gas in a galaxy are remnants of other cosmological forces and have nothing to do with the black hole beams. However, the authors don’t think this is likely because the galaxy mergers that could be one source of causing the “sloshing” happened in the galaxies that had the moving beams and those that didn’t. One would expect the cavities to be present in both types if they were caused by galaxies merging rather than moving jets of particles.

As always, there is more science to do. Thanks to the wonderful world of video streaming, a whole generation of new scientists inspired by the same Death Star could do it.

Learn More:
Chandra – Spotted: ‘Death Star’ Black Holes in Action
Ubertosi et al. – Jet reorientation in central galaxies of clusters and groups: insights from VLBA and Chandra data
UT – It’s Confirmed. M87’s Black Hole is Actually Spinning
UT – The Milky Way’s Black Hole is Spinning as Fast as it Can

Lead Image:
Image from Chandra’s X-Ray and VLBA’s radio data set of a black hole’s jets with “cavities” surrounding it.
Credit: X-ray: NASA/CXC/Univ. of Bologna/F. Ubertosi; Inset Radio: NSF/NRAO/VLBA; Image Processing: NASA/CXC/SAO/N. Wolk

The post Black Holes are Firing Beams of Particles, Changing Targets Over Time appeared first on Universe Today.

On May 20th, 2024, an iceberg measuring 380 square kilometers (~147 mi2) broke off the Brunt Ice Shelf in Antarctica. This event (A-83) is this region’s third significant iceberg calving in the past four years. The first came In 2021, when A-74 broke off the ice sheet, while an even larger berg named A-81 followed in 2023. The separation of this iceberg was captured by two Earth Observation satellites – the ESA’s Copernicus Sentinel-1 and NASA’s Landsat 8 satellites – which provided radar imaging and thermal data, respectively.

The iceberg has been officially designated A-83 by the U.S. National Ice Center, which assigns names based on the Antarctic quadrant where the iceberg was first sighted. Since Brunt is located in the eastern Weddell Sea, its bergs receive an ‘A’ designation while the numbers are assigned sequentially. Routine monitoring of ice shelves by satellites allows scientists to track the effects of Climate Change in remote regions like Antarctica. In particular, scientists can monitor how ice shelves retain their structural integrity in response to changing ice dynamics and increases in atmospheric and ocean temperatures.

Brightness temperature data from the U.S. Landsat 8 mission. Credit: ESA/USGS

This calving event (like its predecessors) was caused by the weakening of the ice at the McDonald Ice Rumples and the extension of the ‘Halloween Crack’ into the ice shelf. The Copernicus Sentinel-1 mission relies on radar imaging to return images throughout the year, regardless of whether it’s day or night. This is especially important during the winter when there is virtually no sunlight for six months (known as Antarctic Night). Missions like Landsat 8 rely on thermal imaging to help scientists characterize ice sheet thickness.

As the image above shows, the thinner ice appears warmer since it is closer in temperature to open water, while thicker continental ice appears darker. The temperature differences between the ocean and ice sheets also help scientists identify where the calving line is. Fortunately, the iceberg does not threaten the British Antarctic Survey’s Halley VI Research Station, an international research platform that observes Earth, atmospheric, and space weather. While it is still located on the Brunt Ice Shelf, the station was relocated in 2017 to the Caird coast after the outer ice shelf was deemed unstable.

The ongoing loss of Antarctic ice is one of the clearest indications of rising global temperatures and a dire warning. In addition to contributing to rising sea levels, coastal flooding, and extreme weather, the loss of polar ice leads to additional solar radiation being absorbed by Earth’s oceans, causing temperatures to rise further. Monitoring the polar ice sheets is vital to adaptation and mitigation strategies, as spelled out in the IPCC’s Sixth Assessment Report (AR6).

Further Reading: ESA

The post Another Giant Antarctic Iceberg Breaks Free appeared first on Universe Today.

Four zebrafish are alive and well after nearly a month in space aboard China’s Tiangong space station. As part of an experiment testing the development of vertebrates in microgravity, the fish live and swim within a small habitat aboard the station.

While the zebrafish have thus far survived, they are showing some signs of disorientation. The taikonauts aboard Tiangong – Ye Guangfu, Li Cong, and Li Guangsu – have reported instances of swimming upside down, backward, and in circular motions, suggesting that microgravity is having an effect on their spatial awareness.

The zebrafish were launched aboard Shenzhou-18, which carried them, as well as a batch of hornwort, to orbit on April 25, 2024. The aim of the project is to create a self-sustaining ecosystem, studying the effects of both microgravity and radiation on the development and growth of these species.

As a test subject, zebrafish have several advantages. Their short reproductive and development cycle, and transparent eggs, allow scientists to study their growth quickly and effectively, and their genetic makeup shares similarities with humans, potentially offering insights that are relevant to human health. The zebrafish genome has been fully sequenced, and for these reasons zebrafish are commonly used in scientific experiments on Earth. Seeing how these well-studied creatures behave in such an extreme environment may have a lot to tell us about the life and development of vertebrates across species while exposed to microgravity.

The developmental stages of a zebrafish (danio rerio). Ed Hendel, Wikimedia Commons.

The taikonauts aboard Tiangong perform feeding and water sampling at regular intervals, and cameras allow scientists on the ground to monitor the aquarium.

This is not the first time fish have been to space. Starting in 2012, a Japanese research project brought medaka and zebrafish to the International Space Station for study in a similar aquatic habitat. The results of those studies revealed a decrease in bone density in the fish within just ten days. Human astronauts experience similar effects in orbit, though not on such quick time scales, and they can be mitigated somewhat through rigorous exercise routines.

Earlier fish in space include a mummichog aboard Skylab 3 in 1973 (and again in 1975 aboard Apollo-Soyuz), and zebrafish aboard the Soviet space station Salyut 5 in 1976. A variety of fish reached orbit aboard space shuttles in the 1990s, too.

The health and sustainability of animal life in space is a key area of research for human spaceflight efforts. If humans are to travel on long-term space missions, like those required to reach Mars, then understanding the biological implications of space travel is vital. These zebrafish are the latest in a long line of experiments undertaken in this pressing area of research.  

Learn More:

Gong Zhe “Aquatic antics: Fish exhibit disorientation in China Space Station.” CGTN.

The post Fish are Adapting to Weightlessness on the Chinese Space Station appeared first on Universe Today.

The hunt for new exoplanets continues. On May 23rd, an international collaboration of scientists published the NASA TESS-Keck Catalog, an effort to publicly release over 9000 radial velocity measurements collected by NASA’s space-based Transiting Exoplanet Survey Satellite (TESS) and the ground-based Keck Observatory, located in Hawai’i, and the Automated Planet Finder, located at the Lick Observatory in California. An accompanying analysis of these validated 32 new planetary candidates and found the masses of 126 confirmed planets and candidates with a wide range of masses and orbits. Let’s dig into some details.

Radial velocity (RV) measurements are a backbone of exoplanet hunting. Telescopes collect data on how a star “wobbles” by checking for a red-shift (if it’s moving toward the Earth) or blue-shift (if it’s moving away) based on the gravitational pull of an exoplanet orbiting it. If the data presents a repeating pattern, the scientists know they have a likely exoplanet candidate on their hands.

To calculate the planet’s rotational period, scientists use the frequency of the changes in light from the star. They can estimate a planet’s orbital period based on how quickly the star cycles through the red and blue shifts they would expect from a complete planetary orbit. Unfortunately, since telescope time is limited, most of the exoplanets found so far using this method have much shorter orbital periods than the Earth.

Fraser discusses the end of TESS’s first mission.

Calculating a planet’s mass is also possible using the RV method – simply by calculating the planet’s gravitational pull as it is either directly behind or in front of the star. The magnitude of the respective red or blue shift can be directly tied to the planet’s mass, causing the gravitational pull.

Some truly unique worlds are hiding in the data, with two that stood out enough to be mentioned in a press release from the Keck Observatory. One is an overweight version of a “sub-Neptune”,” while another is a rapidly orbiting “super-Earth”.” 

A “sub-Neptune” is a category of planet that is a gas giant slightly smaller than Neptune, the smallest gas giant in our solar system. A planet known as TOI-1824 falls into this category but has a unique weight – it’s 19 times as massive as Earth despite being only about 2.6 times its size. That is an extremely dense planet and well outside of the range of other typical sub-Neptunes, which typically vary between 6 and 12 times the mass of our own planet.

TESS has had plenty of data updates over its lifetime – Fraser discusses one here.

A planet in the dataset that is closer in size to our own is TOI-1798c. From the mass perspective, it’s about the same size as Earth. However, it is so close to its parent’s star that it orbits it every 12 hours. This puts it in the category of an “Ultra-short period” (USP) orbit. Typically, USPs are tidally locked to their star and blasted with massive amounts of radiation. Estimates put the solar radiation it receives from its host star at 3000 times that received by the Earth. It doesn’t sound like an enjoyable vacation spot.

Doubtless, other exoplanets are hiding in the trove of data released as part of this paper. And each of those unique systems warranted their own published paper as well. As humanity begins to collect more and more discovered exoplanets, more strange and exciting new worlds will be found. It’s a crazy galaxy out there, and we’re only just starting to explore it.

Learn More:
Keck Observatory – New Catalog Showcases a Diverse Exoplanet Landscape with Strange, Exotic Worlds
Polanski et al. – The TESS-Keck Survey. XX. 15 New TESS Planets and a Uniform RV Analysis of All Survey Targets
UT – TESS Has Found Thousands of Possible Exoplanets. Which Ones Should JWST Study?
UT – Six Planets Found Orbiting an Extremely Young Star

Lead Image:
Artist’s rendering of some of the exoplanets contained in the TESS-Keck Catalog.
Credit – W. M. Keck Observatory / Adam Makarneko

The post Marvel at the Variety of Planets Found by TESS Already appeared first on Universe Today.

In just a few short years, NASA hopes to put humans back on the lunar surface. The first moonwalk in more than 50 years is scheduled for no earlier than September 2026 as part of the Artemis III mission. In preparation, astronauts, scientists, and flight controllers are conducting simulated spacewalks here on Earth.

“Field tests play a critical role in helping us test all of the systems, hardware, and technology we’ll need to conduct successful lunar operations during Artemis missions,” said Barbara Janoiko of NASA’s Johnson Space Center. “Our engineering and science teams have worked together seamlessly to ensure we are prepared every step of the way for when astronauts step foot on the Moon again.”

Astronauts Kate Rubins and Andre Douglas donned mock spacesuits and test gear for a week of simulated moonwalking near Flagstaff, Arizona, where a volcanic desert served as a stand-in for the lunar surface.

NASA astronaut Kate Rubins observes a geology sample she collected during a simulated moonwalk.
NASA/Josh Valcarcel

The tests were multipurpose, making sure that communications protocols with mission control were effective, putting technological devices that will used by moonwalkers through their paces, and doing dry runs of science-related activities, such as gathering geology samples.

The technology tested included an augmented reality visor that could provide navigational information to astronauts, helping them stay oriented and relocate the lunar lander in an emergency.
The test also simulated the communications procedures, allowing both astronauts and ground-based- teams to work together remotely to retrieve the most valuable geological samples and problem-solve in real-time.

“During Artemis III, the astronauts will be our science operators on the lunar surface with an entire science team supporting them from here on Earth,” said Cherie Achilles, science officer for the test at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This simulation gives us an opportunity to practice conducting geology from afar in real-time.”

NASA astronaut Andre Douglas collects soil samples during the first in a series of four simulated moonwalks in Arizona. NASA/Josh Valcarcel

All told the astronauts performed four ‘moonwalks’ and six technology demonstrations over the course of the week. These activities represent the fifth in a series of field tests, and are the “highest fidelity Artemis moonwalk mission simulation to date,” according to a NASA press release.

Artemis III is targeting the lunar south pole, which is a new environment for humans, far removed from the landing sites of the Apollo mission of 1969-72. The permanently shadowed craters of the south pole are expected to hold water ice, a valuable resource in space not just as a refreshing drink, but also as a source of the primary ingredients (hydrogen and oxygen) needed to make rocket fuel.

Rubins and Douglas’s space suits were open-sleeved for the Arizona desert, but prototypes of the actual spacesuits, currently under development by Axiom Space, are also undergoing testing. Future tests will have them put through their paces underwater at NASA’s Neutral Buoyancy Laboratory in Houston, Texas.

Learn More:

“NASA Tests Technology, Practices Artemis Moonwalks in Arizona Desert.” NASA.

The post NASA is Practicing for the Moon With Partial Space Suits appeared first on Universe Today.

The search for life in the Universe has fascinated humans for centuries. Mars has of course been high on the list of potential habitats for alien existence but since the numerous spacecraft images that have come back showing a barren landscape, it seems Mars may not be so habitable after all. That is, until recently. The Martian regolith, the top layer of dust upon the surface has been found to be full of perchlorate salts.  These chemicals are poisonous to most life on Earth but a new study suggests that some extremophile protein enzymes and RNA may just be able to survive!

Mars is the fourth planet from the Sun and the last of the major planets to have a solid surface. To the casual observer, Mars has a red hue to it which is the result of an iron-oxide rich surface. You might known iron-oxide by its more familiar name of rust. It is about half the size of Earth but does have some familiar surface features. Volcanoes pepper the surface but these are, as far as we know, extinct and caps of ice adorn the polar regions. 

Featured Image: True-color image of the Red Planet taken on October 10, 2014, by India’s Mars Orbiter mission from 76,000 kilometers (47,224 miles) away. (Credit: ISRO/ISSDC/Justin Cowart) (This file is licensed under the Creative Commons Attribution 2.0 Generic license.)

Early observers, with poor quality telescopes believed Mars was criss-crossed with a great global irrigation system that carried melt water from the polar caps to the drier equatorial regions. We have since learned that these were just optical illusions and that the polar caps were largely made of carbon dioxide ice. As time progressed, the expectations of finding alien life on Mars slowly dwindled away. It has been kept alive though with hints of surface liquid water making the odd appearance and chemicals found in Martian meteorites that suggest biological processes. There is no doubt that the debate of life on Mars has still not reached a conclusion.

As we continue to search for evidence of life we are in parallel expanding our knowledge of life on Earth. In our search, whichever way we turn, under whichever rock we look or even indeed whichever corner of the world we search we can find signs of life. No matter how extreme the environment, life seems to find a way and as we learn more about the conditions where life can exist here, it helps in our search for alien life too. 

Among the many missions to Mars, there is mounting evidence for perchlorate salts in the Martian surface. These salts are composed of oxygen and chlorine atoms and are usually considered to be harmful to life on Earth. They can combine with water in the atmosphere to produce solutions of brine (salty water). The presence of water in many different states on Mars has informed NASA’s strategy for the search for life there to ‘follow the water’. The concept is simple, look for water and you may find life! 

A team of researchers at the College of Biological Sciences have recently published their research in the Nature Communication journal. They studied how the geochemical environment on Mars could shape and support past, or even present life on the red planet! Led by Assistant Professor Aaron Engelhart, the team studied two types of RNA (ribonucleic acid) and enzymes that are key components to life on Earth. To their surprise they found that, while the RNA functioned well in the perchlorate brine, the enzymes were less suited. They did find though that proteins that have evolved to survive extreme environments on Earth were well suited to the brine solution. 

It is a tantalising twist to the hunt for life. Where we started to lose hope for finding signs of past or present life on Mars due to the hospitable environment, the results showed that RNA is actually well suited to salty properties of the brine. With tolerance to such environmental factors the research breathes tantalising new angles into the search for life. 

Source : Exploring extremes in the search for life on Mars

The post Toxic Perchlorate on Mars Could Make Life More Interesting appeared first on Universe Today.

The Universe wants us to understand its origins. Every second of every day, it sends us a multitude of signals, each one a clue to a different aspect of the cosmos. But the Universe is the original Trickster, and its multitude of signals is an almost unrecognizable cacophony of light, warped, shifted, and stretched during its long journey through the expanding Universe.

What are talking apes to do in this situation but build another telescope adept at understanding a particular slice of all this noisy light? That’s what astronomers think we should do, to nobody’s surprise.

Due to the size of the Universe and its ongoing expansion, light from the Universe’s first galaxies is stretched into the infrared. This ancient light holds clues to the Universe’s origins and, by extension, our origins. It takes a powerful infrared telescope to sense and decipher this light. Earth’s atmosphere blocks infrared light which is why we keep building infrared space telescopes.

Infrared telescopes are also well-suited to observing planets as they form. Dense environments like protoplanetary disks are opaque to most light, but infrared light can reveal what’s going on in these planet-forming environments. The dust absorbs light, then emits it in the infrared, and also scatters it. That confounds optical telescopes, but infrared telescopes like SALTUS are designed to deal with it.

A team of astronomers from the USA and Europe has joined the chorus calling for a new infrared space telescope. It’s tentatively called SALTUS, the Single Aperture Large Telescope for Universe Studies. In a new paper, the astronomers outline the science case for SALTUS.

“The SALTUS Probe mission will provide a powerful far-infrared (far-IR) pointed space observatory to explore our cosmic origins and the possibility of life elsewhere,” write the authors of the new paper.

The paper is titled “Single Aperture Large Telescope for Universe Studies (SALTUS): Science Overview.” Gordon Chin from NASA’s Goddard Space Flight Center is the lead author. It’s in pre-print at arxiv.org.

If built, SALTUS will be different from the powerful JWST. The JWST has four instruments that cover an infrared frequency range from 600 to 28,500 nanometers, or 0.6 to 28.5 microns, which is from the near-infrared (NIR) to the mid-infrared (MIR). SALTUS would cover 34 to 660 ?m, which is in the far-infrared (FIR). SALTUS’ range is unavailable to any current observatory, space or ground-based.

There are no precise definitions of what exact ranges constitute NIR, MIR, and FIR, but this table is a useful representation. Image Credit: Wikipedia

Infrared telescopes need to be kept cool. They use sunshades and cryogenic coolers to keep temperatures down and IR light detectable. The longer the wave of infrared light, the cooler the sensor needs to be. Sunshades are passive and cool the primary mirror, but the instruments require active cryogenic cooling, and those systems have a limited lifetime that restricts mission length. In SALTUS’s case, the baseline mission length is five years.

During those five years, SALTUS will make use of its 14-meter primary mirror and its pair of instruments to open a “powerful window to the Universe through which we can explore our cosmic origins,” according to the paper’s authors.

The two instruments are the SAFARI-Lite spectrometer (SALTUS Far-Infrared Lite) and HiRX (High-Resolution receiver.) Using these instruments, SALTUS will complement the observing capabilities of the JWST and ALMA, the Atacama Large Millimetre/submillimetre Array.

Its aperture is so large that it’ll be the only Far-IR observatory with arcsec-scale spatial resolution. One arcsecond is defined as the ability to show two posts standing 4.8mm apart from 1km away as separate posts. “This will permit an unmasking of the true nature of the cold Universe, which holds the answers to many of the questions concerning our cosmic origins,” the authors write.

SALTUS has a unique design among space telescopes. It features an inflatable primary mirror, which is new to space telescopes but has been proven during decades of use in ground-based telecommunications. A two-layer sunshield will keep the inflatable mirror cool.

SALTUS large aperture will provide high sensitivity and is aimed at a couple of foundational questions.

How does habitability develop while planets are forming? To address this question, SALTUS will trace carbon, oxygen, and nitrogen in 1,000 different protoplanetary disks. It has the power to recognize numerous molecular and atomic species and different lattice modes of ice and some minerals. No existing telescope has this capability.

SALTUS’ far IR observing capabilities will let it see a portion of protoplanetary disks that are obscured in other wavelengths. This will open a new window into planet formation and how habitability develops. Image Credit: Chin et al. 2025/Miotello et al. Protostars and Planets 2023.

Habitability, as far as we understand it, revolves around water. Water begins its journey in the same molecular clouds where stars form. SALTUS will follow water’s journey from molecular cloud to protoplanetary disks to icy planetesimals and comets that deliver water to planets like Earth. A key part of SALTUS’s work will be deriving deuterium/hydrogen ratios.

This simple graphic shows how water arrives on planets and can lead to habitability. SALTUS will follow the water’s journey by observing hundreds of protoplanetary disks. Image Credit: Chin et al. 2024.

How do galaxies form and evolve? SALTUS will measure how galaxies form and acquire more mass. It’ll measure heavy elements and interstellar dust from the Universe’s first galaxies to today. The telescope will also probe the co-evolution of galaxies and their supermassive black holes (SMBHs.)

Tracking the rapid evolution of dust grains in galaxies in the Universe’s first billion years is part of understanding galaxy formation and evolution. SALTUS can do that by observing PAHs, polycyclic aromatic hydrocarbons, and their spectral lines. Some PAH spectral lines are very faint but entirely visible to SALTUS.

There’s a causal link between star formation and active galactic nuclei (AGN) that influences galaxy growth and evolution. But the two phenomena take place on wildly different spatial scales, and the phase that links them together is obscured by dust. SALTUS’s high resolution and sensitive far-IR spectroscopy will give astronomers a clearer view of AGN and how they shape galaxies.

SALTUS would be placed into a Sun-Earth Halo L2 orbit. Its maximum distance from Earth would be 1.8 million km (1.12 million miles). That orbit would give the telescope two continuous 20º viewing zones around the ecliptic poles, resulting in full sky coverage every six months.

The SALTUS concept is designed in response to the 2020 Decadal Survey and NASA’s Astrophysical Roadmap. It’s a direct response to NASA’s 2023 Astrophysics Probe Explorer (APEX) solicitation. The questions it’ll help answer come directly from those works.

“SALTUS has both the sensitivity and spatial resolution to address not just the open science questions of the year 2023 but, more importantly, the unknown questions that will be raised in the 2030s,” the authors write in their summary. “SALTUS is forward-leaning and well-suited to serving the current and future needs of the astronomical community.”

The post Astronomers Propose a 14-Meter Infrared Space Telescope appeared first on Universe Today.

The parade of interesting new exoplanets continues. Today, NASA issued a press release announcing the discovery of a new exoplanet in the Gliese 12 system, sized somewhere between Earth and Venus and inside the host star’s habitable zone. Two papers detail the discovery, but both teams think that the planet is an excellent candidate for follow-up with the James Webb Space Telescope (JWST) to try to tease out whether it has an atmosphere and, if so, what that atmosphere is made of.

But before JWST knew where to look, another workhorse of the exoplanet hunt had to do its job. The Transiting Exoplanet Survey Satellite (TESS) found this planet in a system only 40 light years away. That would make it the closest known example of a rocky, Earth or Venus-sized exoplanet in its star’s habitable zone.

Gliese 12 is a red dwarf, only weighing about 27% of the Sun’s weight. Due to the intricacies of fusion, this amounts to the star outputting about 60% of the light of our Sun, which, in turn, means its habitable zone is much closer than our own. The planet, known as Gliese 12b, orbits its parent star once every 12.8 days. But more importantly, it receives about 85% of the energy that Venus typically receives from the Sun.

Fraser discusses some of the accomplishments of TESS.

The similarity between our closest neighbor and this exoplanet is striking. It could also lead to new discoveries about the formation of our solar system. Current theory holds that Venus and the Earth originally had an atmosphere and then lost it. They diverged to become the Eden-like Earth and the hell-like Venus because of one crucial substance – water.  

Venus’ atmosphere lacked water, so when its current atmosphere started to form, none of the liquid necessary for life as we know it was available. Earth, on the other hand, had plenty of water to spare, allowing it to eventually develop life and humans to evolve there.

One of the holy grails of astrobiology is to find an Earth analog, where the solar radiation, day length, size, atmospheric makeup, and other factors are similar enough for a reasonable chance for life to evolve. We can quickly determine many of those numbers, such as orbit, size, and the amount of solar radiation a planet receives. But finding details like atmospheric makeup is harder.

Artist’s depiction of Gliese 12b in comparison to Earth, with different atmospheres – from no atmosphere at all on the left to a atmosphere like Venus’ on the right.
Credit – NASA / JPL-Caltech/R. Hurt (Caltech/IPC)

Hence why the researchers suggested JWST should get involved. The world’s most powerful space-based telescope would be capable of detecting the atmospheric makeup of Gliese 12b using a technique called transmission spectroscopy. That’s when the light from a planet’s host star is forced through the planet’s atmosphere, and what wavelengths are absorbed can give an astronomer an idea of what kind of gases are present in that atmosphere.

For now, it’s pure speculation whether Gliese12b has any atmosphere. But with some observational time on JWST, scientists should be able to answer that question easily. Until then, workhorses like TESS will keep picking up new exoplanet candidates for JWST to look at. There are undoubtedly some more interesting ones hiding out there amongst the stars—it’s only a matter of time before we find them.

Learn More:
Kuzuhara et al. – Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Transmission Spectroscopy
Dholakia et al.- Gliese 12 b, a temperate Earth-sized planet at 12 parsecs discovered with TESS and CHEOPS
UT – TESS Finds Eight More Super-Earths
UT – Hubble Succeeds Where TESS Couldn’t: It Measured the Nearest Transiting Earth-Sized Planet

Lead Image:
Artist’s depiction of Gliese 12b and its parent star.
Credit – NASA / JPL-Caltech / R Hurt (Caltech-IPAC)

The post A New Venus-Sized World Found in the Habitable Zone of its Star appeared first on Universe Today.

I love the concept of a ‘puffy’ planet! The exoplanets discovered that fall into this category are typically the same size of Jupiter but 1/10th the mass! They tend to orbit their host star at close in orbits and are hot but one has been found that is different from the normal. This Neptune-mass exoplanet has been thought to be cooler but still have a lower density. The James Webb Space Telescope (JWST) has recently discovered that tidal energy from its elliptical orbit keeps its interior churning and puffs it out. 

WASP-107b is more than three quarters the volume of Jupiter but, like most fluffy planets, is one-tenth the mass making it one of the least dense planets known. Its unusual property however is that whilst most puffy planets are hot, WASP-107b is relatively cool. This goes against initial observations which had also suggested, due to its mass, radius and age it was thought to have a small rock core with a hydrogen and helium rich atmosphere.

Recent observations of this exoplanet by the JWST revealed far less methane in the atmosphere than expected. The orientation of the orbit making it edge on to us means we can study the planet’s atmosphere by examining the light from the star as it passes through the gas. This technique known as transmission spectroscopy can be used to identify the signatures of gasses in the star’s spectrum. Using JWSTs Near-Infrared Camera and Mid-Infrared Instrument and data from Hubble’s Wide Field Camera 3, the abundances of methane, water vapour, carbon dioxide, carbon monoxide, sulphur dioxide and ammonia could be revealed.

Artist impression of the James Webb Space Telescope

Not only did this reveal the lack of methane but also provided evidence that hot gas from lower altitudes was mixing with cooler gas layers from higher up. One of the properties of methane is that it is unstable at high temperatures and, beyond 1200 degrees the bonds between hydrogen and carbon breakdown. This is not the case with other carbon based molecules suggesting the higher temperature.  It suggests that the interior of the planet must be hotter than thought with a more massive core than expected. It’s thanks to JWST’s higher level of sensitivity that the mystery looks like it may finally have been solved.

The team, led by Luis Welbanks from Arizona State University (ASU) explored a number of possibilities. First that it had more mass in its core than first expected. If this was true then the atmosphere is likely to have contracted as the planet cooled. In time and, without a source of heat to give the atmosphere energy and cause it to expand, the planet should be much smaller than observed. Even though the planet orbits the star at a distance of of just over 8 million kilometres it still does not get enough energy to drive the inflation of the atmosphere. 

One theory is that the higher internal temperatures are generated by tidal heating. In just the same way that the gravitational force of Jupiter causes tidal heating on Io, the highly elliptical orbit of WASP-107b could be the answer. As the planet swings by the host star in its non-circular orbit it is squished and squashed providing a source of heat. 

Understanding the source of heat on WASP-107b has helped the team learn more about the properties and processes. Knowing how much energy is there helps to determine the proportions of other elements like carbon, nitrogen, oxygen and sulphur. Calculating this helps to determine the mass of the core  which, according to the recent studies reveal is twice as massive as originally estimated.

Source : Webb Cracks Case of Inflated Exoplanet

The post Webb Explains a Puffy Planet appeared first on Universe Today.

It’s been 20 years in the making, but a 3200-megapixel camera built especially for astrophysics discoveries has finally arrived at its home. The Legacy of Space and Time (LSST) camera was delivered to the Vera C. Rubin Observatory in Chile in mid-May, 2024.

The camera traveled from its construction lab at the SLAC National Accelerator Laboratory. The technical crew outfitted it with specialized data loggers, monitors, and GPS attached to track the conditions of its trip. Then they put it into a specially built container and the whole assemblage made the trip from San Francisco airport to Santiago on the 14th of May via a chartered flight. Once in Chile, it traveled up to the site for five hours up a 35-kilometer dirt road. It arrived on the 16th, completing a huge step toward opening the Rubin Observatory, according to construction project manager. “Getting the camera to the summit was the last major piece in the puzzle,” he said. “With all Rubin’s components physically on-site, we’re on the home stretch towards transformative science with the LSST.”

This video documents the journey of the LSST Camera from SLAC National Accelerator Laboratory in California to Rubin Observatory on the summit of Cerro Pachón in Chile. The camera arrived on the summit on 16 May 2024. Credit:RubinObs/NSF/AURA/S. Deppe/O. Bonin, T. Lange, M. Lopez, J. Orrell (SLAC National Lab)

The LSST Camera is the final major component of Rubin Observatory’s Simonyi Survey Telescope to arrive at the summit. It’s about the size of a small car. Inside, its focal plane contains 189 CCD sensors arranged on an array of “rafts”. The sensors deliver a combined 3200-megapixel view.

Now that it has arrived, the camera undergoes several months of testing in the observatory’s white room. After that, it goes on the Simonyi Survey Telescope, with its newly-coated 8.4-meter mirror and 3.4-meter secondary mirror.

About the Vera Rubin Observatory

This unique observatory is named after astronomer Vera C. Rubin. Her work focused on the mysterious “dark matter” that seems to permeate the Universe. Along with her team, she studied dozens of galaxies to understand what was influencing their motions. It turned out to be dark matter. The search for dark matter and its existence throughout the Universe is one of the main goals of the observatory that now bears her name.

Understanding the distribution of dark matter is where the LSST Camera will come in handy. For one thing, it will spend a decade taking images of the sky each night, performing a massive survey that will provide a complete image of the visible sky every 3-4 mights. Each area it images will be about the size of 40 full moons and the survey will take advantage of the 8.4-meter telescope moving quickly between imaging positions. In full operation, the Observatory will deliver a 500-petabyte set of images and data products about the sky.

The complete focal plane of the future LSST Camera is more than 2 feet wide and contains 189 individual sensors that will produce 3,200-megapixel images. Crews at SLAC have now taken the first images with it. (Jacqueline Orrell/SLAC National Accelerator Laboratory)

Not only will the Rubin Observatory perform this unprecedented survey in very high resolution, but will also track objects that change in brightness—called “transients.” That includes supernovae, variable stars, mergers of dense objects such as neutron stars or black holes, and other quickly changing events and objects. In addition, it will track asteroids and other objects that wander through the Solar System.

The formation and evolution of the Milky Way Galaxy is another research area for telescope users. Rubin should be able to track stellar streams throughout the Galaxy and chart their paths. That information could give precious insight into just how our Galaxy formed and how stars from cannibalized galaxies move through it.

What’s Next for Vera Rubin Observatory and the LSST Camera

Once the LSST Camera got delivered to the Cerro Pachón site, technicians moved it into an immense white room. That’s a controlled environment that protects the instrument while they work to get it ready for installation on the telescope. They inspected the camera and downloaded data about the “ride” from the U.S. to Chile from all the instruments attached to it. “Our goal was to make sure the camera not only survived, but arrived in perfect condition,” said Kevin Reil, Observatory Scientist at Rubin. “Initial indications—including the data collected by the data loggers, accelerometers, and shock sensors—suggest we were successful.”

View of Rubin Observatory at sunset in December 2023. The 8.4-meter telescope at Rubin Observatory, equipped with the highest-resolution digital camera in the world, will take enormous images of the southern hemisphere sky, covering the entire sky every few nights. Rubin will do this over and over for 10 years, creating a timelapse view of the Universe. Image Credit: RubinObs/NSF/AURA/H. Stockebrand

The observatory is still in the final stages of construction. The telescope is in place, and other instruments and infrastructure are being finalized. It should all be ready for “first light” and the beginning of science operations sometime in 2025. Between now and then, more parts of the telescope and its mirrors should be installed, and there will be tests of various other instruments both on and off the sky as scientists get ready to start using Rubin next year. Once observations begin, astronomers using Rubin could discover around 17 billion stars and ~20 billion galaxies in the distant Universe.

For More Information

LSST Camera Arrives at Rubin Observatory in Chile, Paving the Way for Cosmic Exploration
Vera C. Rubin Observatory

The post The Largest Camera Ever Built Arrives at the Vera C. Rubin Observatory appeared first on Universe Today.