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Getting a mission to the point of officially being accepted for launch is an ordeal. However, even when they aren’t selected for implementation, their ideas, and in some cases, their technologies, can live on in other missions. That was the case for the Oversize Kite-craft for Exploration and AstroNautics in the Outer Solar system (OKEANOS) project, originally planned as a Japanese Aerospace Exploration Agency (JAXA) mission. Despite not receiving funding to complete its entire mission, the project team released a paper that details the original plan for the mission, and some of those plans were incorporated into other missions that are still under development.

OKEANOS sought to build on JAXA’s success in returning samples from asteroids to Earth. Its most well-known mission in that regard was Hayabusa-2, which returned samples from the asteroid Ryugu in 2020 and has been the subject of dozens of scientific papers since. Ryugu is a near-earth asteroid, which means its origins in the solar system are dramatically different from those of other asteroids farther out from the Sun, which is where OKEANOS came in.

The original plan for OKEANOS was to launch a sample return mission to one of the Jupiter Trojan asteroids that sit in the Lagrange points in front of and behind Juptier and its orbital path. Scientists believe these asteroids originated outside of Neptune’s orbit in the Kuiper belt but were brought closer to the Sun due to gravitational fluctuations caused by the migration of the gas giant planets. Since they would hold clues to the early solar system, astronomers are interested in their composition, and some space exploration enthusiasts are interested in the materials they hold for in-situ resource utilization purposes. But so far, no missions have visited them yet.

A solar panel, like the one shown in the video, would have been a key component of the OKEANOS missions.
Credit – The Japan Times YouTube Channel

That is about to change, though, with Lucy, a NASA mission that launched in 2021 to visit them. However, Lucy will simply do remote observations and lacks the equipment to sample them directly, let alone return a sample back to Earth. The project team had hoped OKEANOS would do just that.

Several novel technologies would be used to enable OKEANOS’ scientific objectives. One of the most interesting was a combination solar sail and ion drive known as a solar power sail. A solar power sail combines the solar pushing power of a solar sail with flexible photovoltaic solar collectors that can collect a significant amount of energy while deployed in a sail-like configuration. JAXA has also successfully tested a similar system with its IKAROS mission, demonstrating the technology in 2010.

Since solar sails have tiny thrust out near Jupiter, OKEANOS relies entirely on an ion engine and simply deploys its “sails” to deploy the solar panels that collect energy to power the ion drive. But once it reached its destination, it would utilize its second interesting technology—a lander.

Fraser talks about Lucy, the first mission to explore the Trojan asteroids.

The two main asteroid sample return missions – OSIRIS-REx and Hayabusa-2 – directly touched down on the surface of their respective asteroids. However, there have been deployed landers that have at least attempted to land on an asteroid before – Philae, the lander that accompanied ESA’s Rosetta mission, is probably the most famous. But never before has a mission attempted to land a lander, collect a sample, and return it to a “mothership” that would then transport that sample back to Earth. Doing so out at the Trojan asteroids would add a new difficulty level of having significant communications lag time, making it difficult to troubleshoot any problems with the mission.

Given JAXA’s track record, it seemed likely that they could pull off that technical challenge. However, the mission was never fully funded due to a “cost issue,” according to the paper. JAXA selected a project known as LiteBIRD to study the cosmic microwave background as its large-class mission for this decade instead. Despite that, the technical details of some of the instrumentation have been described in other papers, and the project team feels confident that future asteroid sample return missions will adopt at least some of them. We’ll be sure to see more of those in the future as interest grows in understanding the roots of our solar system and how we might utilize the readily available resources on asteroids.

Learn More:
Takao et al. – Sample return system of OKEANOS—the solar power sail for Jupiter Trojan exploration
UT – Lucy Adds Another Asteroid to its Flyby List
UT – Separation Camera Takes Full Images and ‘Movie’ of IKAROS Solar Sail
UT – Tiny Fragments of a 4-Billion Year Old Asteroid Reveal Its History

Lead Image:
Concept images of the OKEANOS mission.
Credit – Takao et al.

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NGC 4594 is an unusual galaxy. It was discovered in 1781 by Pierre Méchain, and is striking because of a symmetrical ring of dust that encircles the visible halo of the galaxy. Images taken of the galaxy in 2003 show this dusty ring in detail, where it almost resembles the brim of a large hat. So it’s understandable that NGC 4594 is more commonly known as the Sombrero Galaxy. Now the James Webb Space Telescope has captured an amazingly sharp image of the galaxy, and it’s revealing some interesting surprises.

The famous Sombrero galaxy. The prominent dust lane and halo of stars and globular clusters give this galaxy its name. Credit: NASA/ESA and The Hubble Heritage Team (STScI/AURA)

Although Hubble’s view of the Sombrero Galaxy is stunning, it is bound by the limits of the optical spectrum. In the Hubble image, the thick dust ring obscures any stars that may be forming within it, and the brilliance of the active black hole at the heart of the galaxy outshines any details at the center of the galaxy. Given what we know about galaxies and star formation, it was thought that the dust ring could hide stellar nurseries where new stars are being born. And the central region of the galaxy likely held a bulge of stars similar to that of other galaxies.

The JWST image reveals a very different story. This particular image was captured by Webb’s Mid-Infrared Instrument (MIRI), which can peer through much of the galaxy’s dust. It reveals clumps of warm molecular gas within the brim of the galaxy, but surprisingly few young stars. It appears that the dust ring is not a significant source of star formation. The image also unveils the central region of the galaxy. Rather than a halo of stars surrounding the black hole, there is a flat disk. While the central black hole is active, it is a low luminosity galactic nucleus, which is again surprising given that it does produce jets of plasma like more active galactic nuclei.

Overall, the Sombrero Galaxy is much more unusual than we expected, and while these are only the first detailed images from the Webb, they already promise to yield a wealth of data. Future observations will likely focus on the globular clusters of the galaxy. There are about 2,000 globular clusters within the Sombrero Galaxy, which is unusually high for a galaxy of its size. This could help explain why NGC 4594 is so different from other galaxies.

You can find more images of the Sombrero Galaxy on the Webb Space Telescope website.

The post Fantastic New Image of the Sombrero Galaxy From Webb appeared first on Universe Today.

Astronomers often use the Milky Way as a standard for studying how galaxies form and evolve. Since we’re inside it, astronomers can study it in detail with advanced telescopes. By examining it in different wavelengths, astronomers and astrophysicists can understand its stellar population, its gas dynamics, and its other characteristics in far more detail than distant galaxies.

However, new research that examines 101 of the Milky Way’s kin shows how it differs from them.

One powerful way to understand things is to compare and contrast them with others in their class, a technique we learn in school. Surveys are an effective tool to compare and contrast things, and astronomical surveys have contributed an enormous amount of foundational data towards the effort. The Sloan Digital Sky Survey (SDSS), the Two Micron All Sky Survey (2MASS), and the ESA’s Gaia mission are all prominent examples.

The Satellites Around Galactic Analogs (SAGA) Survey is another, and its third data release features in three new studies. The studies are all based on 101 galaxies similar in mass to the Milky Way, and each study tackles a different aspect of comparing those galaxies to ours.

• The SAGA Survey. III. A Census of 101 Satellite Systems around Milky Way–mass Galaxies
• The SAGA Survey. IV. The Star Formation Properties of 101 Satellite Systems around Milky Way–mass Galaxies
• The SAGA Survey. V. Modeling Satellite Systems around Milky Way–Mass Galaxies with Updated UniverseMachine

Research shows that galaxies form inside gigantic haloes of dark matter, the elusive substance that doesn’t interact with light. 85% of the Universe’s matter is mysterious dark matter, while only 15% is normal or baryonic matter, the type that makes up planets, stars, and galaxies. Though we can’t see these massive haloes, astronomers can observe their effects. Their gravity draws normal together to create galaxies and stars.

Dark matter haloes are part of the Large-Scale Structure of the Universe, the cosmic web of dark matter and galaxy clusters and superclusters that make up the Universe’s backbone. Simulated Image Credit: Ralf Kaehler/SLAC National Accelerator Laboratory

SAGA is aimed at understanding how dark matter haloes work. It examines low-mass satellite galaxies around galaxies similar in mass to the Milky Way. These satellites can be captured and drawn into the dark matter haloes of larger galaxies. SAGA has found several hundred of these satellite galaxies orbiting 101 Milky Way-mass galaxies.

“The Milky Way has been an incredible physics laboratory, including for the physics of galaxy formation and the physics of dark matter,” said Risa Wechsler, the Humanities and Sciences Professor and professor of physics in the School of Humanities and Sciences. Wechsler is also the co-founder of the SAGA Survey. “But the Milky Way is only one system and may not be typical of how other galaxies formed. That’s why it’s critical to find similar galaxies and compare them.”

The comparison between the Milky Way and the 101 others revealed some significant differences.

“Our results show that we cannot constrain models of galaxy formation just to the Milky Way,” said Wechsler, who is also professor of particle physics and astrophysics at the SLAC National Accelerator Laboratory. “We have to look at that full distribution of similar galaxies across the universe.”

The SAGA Survey’s third data release includes 378 satellites found in 101 MW-mass systems, and the first paper focuses on the satellites. Only a painstaking search was able to uncover them. Four of them belong to the Milky Way, including the well-known Large and Small Magellanic Clouds.

This figure shows how SAGA compares to other efforts to find satellite galaxies. Image Credit: Mao et al. 2024.

“There’s a reason no one ever tried this before,” Wechsler said. “It’s a really ambitious project. We had to use clever techniques to sort those 378 orbiting galaxies from thousands of objects in the background. It’s a real needle-in-the-haystack problem.”

SAGA found that the number of satellites per galaxy ranges from zero to 13. According to the first paper, the mass of the most massive satellite is a strong predictor of the abundance of satellites. “One-third of the SAGA systems contain LMC-mass satellites, and they tend to have more satellites than the MW,” the paper states. The Milky Way is an outlier in this regard, which is one reason it’s atypical.

The second study focuses on star formation in the satellites. The star formation rate (SFR) is an important metric in understanding galaxy evolution. The research shows that star formation is still active in the satellite galaxies, but the closer they are to the host, the slower their SFR. Is it possible that the greater pull of the dark matter halo close to the galaxy is quenching star formation?

“Our results suggest that lower-mass satellites and satellites inside 100 kpc are more efficiently quenched in a Milky Way–like environment, with these processes acting sufficiently slowly to preserve a population of star-forming satellites at all stellar masses and projected radii,” the second paper states.

However, in the Milky Way’s satellites, only the Magellanic Clouds are still forming stars, with radial distance playing a role. “Now we have a puzzle,” Wechsler said. “What in the Milky Way caused these small, lower-mass satellites to have their star formation quenched? Perhaps, unlike a typical host galaxy, the Milky Way has a unique combination of older satellites that have ceased star formation and newer, active ones – the LMC and SMC – that only recently fell into the Milky Way’s dark matter halo.”

This figure from the research shows the SFR (left) and the specific SFR (right) for the satellite galaxies in the study. The specific SFR differs from the SFR in that it’s divided by the total stellar mass of the galaxy. The specific SFR basically tells astronomers how quickly the galaxy is growing relative to its size. It’s used to compare star formation efficiency across different size galaxies. The grey squares the SAGA hosts and the stars are the Large and Small Magellanic Clouds. Image Credit: Geha et al. 2024.

This is another reason that our galaxy is atypical.

What about the smaller dark matter haloes around the satellite galaxies? What role do they play?

“To me, the frontier is figuring out what dark matter is doing on scales smaller than the Milky Way, like with the smaller dark matter halos that surround these little satellites,” Wechsler said.

The third paper compares SAGA’s third data release with computer simulations. The authors developed a new model for quenching in galaxies with less-than-or-equal-to 109 solar masses. Their model is constrained by the SAGA data on the 101 galaxies, and the researchers then compared it to isolated field galaxies from the Sloan Digital Sky Survey.

The model successfully reproduced the stellar mass function of the satellites, their average SFRs, and the quenched fractions in the satellites. It also maintained the SFR in more isolated satellite galaxies and observed enhanced quenching in closer satellites.

This figure from the research shows the distribution of stellar mass vs. halo mass, with the grey contours representing 2,500 mock Saga-like hosts. It shows that their model successfully reproduces much of what SAGA found. Image Credit: Wang et al. 2024.

The model needs more testing with observations, and the authors point out that spectroscopic surveys are a logical next step. Those surveys can hopefully answer questions about the role internal feedback plays in the lower-mass satellites, about their mass and gas accretion and the influence dark matter has on them, as well as gas processes specific to the satellites.

“SAGA provides a benchmark to advance our understanding of the universe through the detailed study of satellite galaxies in systems beyond the Milky Way,” Wechsler said. “Although we finished our initial goal of mapping bright satellites in 101 host galaxies, there’s a lot more work to do.”

The post We’re Living in an Abnormal Galaxy appeared first on Universe Today.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

When to Watch

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

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

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

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

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

Going to the Grazeline

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

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

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

Observing and Imaging

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Source : NASA Moon Animation

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Before the decade is out, as part of the Artemis Program, NASA plans to send astronauts to the Moon for the first time since the Apollo Era. To realize this goal, they have contracted with commercial space industries to develop all the necessary components. This includes the Space Launch System (SLS) and the Orion spacecraft that will take the Artemis astronauts to the Moon. There’s also the Lunar Gateway and the Artemis Base Camp, the infrastructure that will facilitate regular missions to the Moon after 2028.

In between, NASA has also partnered with companies to develop the Human Landing Systems (HLS) that will transport the Artemis astronauts to the lunar surface and back. This includes the Starship HLS SpaceX is currently developing for NASA, which will rendezvous with the Orion spacecraft in lunar orbit and allow the Artemis III astronauts to land on the Moon (which will take place no sooner than September 2026). In a series of newly-updated images, SpaceX has provided artistic renders of what key moments in this mission will look like.

Artist’s rendering of the Starship tanker transferring propellant to a Starship depot in orbit. Credit: SpaceX

The renderings include a Starship tanker docking with a Starship propellant depot in Low-Earth Orbit (LEO), shown above. These elements are crucial to SpaceX’s long-term plans to send payload and crews to the Moon and Mars, which require that the Starship refuel in orbit so that it can make a trans-lunar injection (TLO) or trans-Mars injection (TMI). For the Artemis missions, this will allow the Starship HLS to reach lunar orbit, where it will rendezvous with the Orion spacecraft. Once there, the Orion will dock with the Starship HLS (shown below), and two Artemis crew members will transfer to the HLS.

The Orion spacecraft docking with the Starship HLS in lunar orbit. Credit: SpaceX

At this juncture, the two astronauts will take the Starship HLS to land near the Moon’s southern polar region (shown below). Similar to how the Starship has conducted many landings here on Earth, this will consist of the spacecraft firing two of its Raptor engines to make a powered descent (shown below). Once the spacecraft safely lands on the Moon (shown at top), the two astronauts will descend to the surface using the spacecraft’s elevator (shown at bottom) and spend approximately a week exploring the South Pole-Aitken Basin, collecting samples, performing science experiments, and observing the Moon’s environment.

Artist’s rendering of the Starship HLS making a braking burn to land on the Moon. Credit: SpaceX

This mission will help pave the way towards creating a lunar settlement in the area, taking advantage of the abundant water ice observed in permanently shadowed regions (PSRs) – i.e., the many craters that dot the Moon’s south pole. While these surface operations take place, the other Artemis crew will await them in orbit. The Starship HLS and its two crewmembers will then launch into lunar orbit and rendezvous with the Orion spacecraft one last time. After returning to the Orion, the entire crew will return home, leaving the Starship HLS in orbit.

Two Artemis III astronauts using the Starship HLS elevator to descend to the surface. Credit: SpaceX

In preparation for the Artemis III mission, SpaceX will perform an uncrewed landing demonstration mission on the Moon. NASA is also working with SpaceX to further develop the HLS to meet the extended requirements for the Artemis IV mission, which is scheduled to launch no sooner than September 2028. This mission will see a crew rendezvous with the Artemis Gateway, which will be launched ahead of time, then land on the lunar surface and conduct extensive science operations. This will include field geology experiments, deploying instruments, and collecting more samples.

Further Reading: NASA

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The Arecibo Message, transmitted on November 16th, 1974, from the Arecibo Observatory, was humanity’s first true attempt at Messaging Extraterrestrial Intelligence (METI). The message was a simple pictorial signal in binary code composed by famed astronomer and SETI researcher Frank Drake (inventor of the Drake Equation) with the assistance of Sagan and other prominent astronomers. The message was and was aimed toward Messier 13 (NGC 6205 or “The Great Hercules Cluster”), a globular star cluster located about 25,000 light-years from Earth in the constellation of Hercules.

In 2018, in preparation for the 45th anniversary of the historic broadcast, the Arecibo Message Global Challenge was launched. Student teams were tasked with designing a new message that could be sent to space, and by August 2020, the Boriken Voyagers team was recognized as the winner of the competition. Unfortunately, the Observatory collapsed on December 1st, 2020, and the message was never sent. To commemorate the 50th anniversary of the Arecibo Message, the Boriken Voyagers have shared “The Last Arecibo Message.”

The Boriken Voyagers team consists of eight students from the University of Arecibo Mayagüez Campus (RUM) and the Planetary Habitability Laboratory (PHL) at the University of Puerto Rico at Arecibo. Boriken is the name for Puerto Rico in the language of the Indigenous Taino/Arawakan people. The group is led by Kelby D. Palencia-Torres, a student at RUM and PHL who specializes in the study of the gas and dust surrounding galactic disks – aka. the Circumgalactic Medium.

The Original Message

The Arecibo Message was organized by Drake in the early 1970s as the first campaign to compose a message destined for space. The effort relied on Arecibo’s megawatt transmitter attached to its 305-meter (1000-foot) antenna to send a 20-gigawatt omnidirectional broadcast. The M13 cluster was selected because of the number of stars (about 300,000) and the cluster’s age (11.65 billion years). This made it seem a likely place to host an extraterrestrial civilization. The message was not intended as an invitation to talk nearly as much as a demonstration of human technological capabilities and scientific knowledge.

The message was transmitted on November 16th, 1974, at a frequency of 2380 MHz and an effective bandwidth of 10 Hz. The message was transmitted at a frequency-shifting rate of 10 bits per second and lasted less than three minutes. It consisted of a 1679-binary digit picture (210 bytes) – the product of two prime numbers – arranged rectangularly into 73 lines of 23 characters per line (also prime numbers). The use of prime numbers was deliberate since mathematics is considered the only “universal language” and easier for an alien civilization to decode.

They conveyed a series of scientific, geographical, biological, and astronomical information in different colors. These included:

• A counting scheme of 1 to 10 (white)
• The atomic numbers for hydrogen, carbon, nitrogen, oxygen, and phosphorus, which make up DNA (purple)
• The chemical formula of the four purines and pyrimidine bases that make up DNA (green)
• An image of the DNA double helix and an estimate of the number of nucleotides (blue and white, respectively)
• A stick figure of a human being (red), our average dimensions (blue/white), and the human population of Earth (white)
• A depiction of the Solar System, indicating that the message is coming from the third planet (yellow)
• A schematic of the Arecibo Observatory and its dimensions (purple/white and blue)

Fifty years after the Arecibo Message was sent, its legacy lives on. Universe Today recently caught up with the Boriken Voyagers to learn more about the original message and their updated version. The team members included Kelby D. Palencia-Torres, Cesar F. Quinones-Martinez, Javier A. Garcia Sepulveda, Luis R. Rivera Gabriel, Lizmarie Mateo Roubert, German Vazquez Perez, and Abel Mendez.

Q: Why does the Arecibo Message endure 50 years later?

Germán Vázquez Pérez: “Even 50 years later, and despite the loss of the Arecibo Observatory, the Arecibo Message continues its journey through the vastness of space, waiting to be intercepted by potential civilizations. It’s a bittersweet feeling. The message remains an example of what humanity can achieve, but we no longer possess the same capability to receive a potential reply or transmit another message with such power and significance. At least for the moment.”

Kelby Palencia-Torres: “The significance of the Message is that it represents humanity, and it is the first intentional message of our existence in the cosmos. The message compels curiosity, and it’s our first step to answering the old question if we are alone in the universe.”

Lizmarie Mateo Roubert: “The Arecibo Message can represent the hope people working in the scientific community have in answering questions about the Universe and all the efforts they have put in throughout the years.”

Cesar Quinones-Martinez: “The Arecibo Message has fascinated many throughout the decades, bringing a lot of debate as to whether or not we should actively contact other extraterrestrial civilizations. Arecibo and the Arecibo Message for Puerto Rico represent a collective curiosity in space exploration, as for many students on the island, visiting Arecibo becomes a key motivator to beginning their STEAM journey. It represents a bold step into the unknown, where our curiosity takes us to make new discoveries. “

Q: How has the field of SETI/METI changed since?

Cesar Quinones-Martinez: “The SETI and METI initiatives both have seen improvements to their capabilities as technology improves. Bigger, more sensitive detectors bring us closer to receiving any artificial signal, while better transmitters could allow for future messages that can better retain their information while passing through gas clouds or other mediums. While the Arecibo Message was designed to showcase Arecibo’s capabilities, current METI projects are more rigorous with what they want to communicate. We do not know the intentions of the recipient of our message, and measures must be taken to be direct with what we say.”

Kelby Palencia-Torres: “With METI, we are more cautious with the content included in the messages. Some sci-fi series like the ‘3 Body Problem’ play a negative role in how METI is perceived outside the scientific community.”

Q: What was it like to compete in the Arecibo Message Global Challenge?

Kelby Palencia-Torres: “The New Arecibo Message Global Challenge was an intriguing and daring competition. To partake and enlist in the challenge, one had to solve a riddle. After this first stage of the challenge, we had to solve a puzzle where the situation was similar to that of the movie Contact. We had to decode a message and identify the location of said message. Once proven to solve the puzzle, we passed to the last stage, where we had to develop the New Arecibo Message. As part of the challenge of the message, we had to consider the energy used to produce the signal and transmit it, choose a location visible to the Arecibo Telescope, and the hardest part … fully create the content of the message itself.”

Lizmarie Mateo Roubert: “At the time, this was truly the most difficult part of the challenge we had encountered so far. Back in 2018, most of us were just beginning our undergraduate degrees and some of the information we needed to keep in mind whenever we were to develop a message in a way that could be encoded eventually proved to be a bit of a struggle. With the help of other professionals in the field and professors on our university campus, we were then able to fully understand how to properly develop this message and the different conditions and capabilities we had to keep in mind so the message could be successfully sent and deciphered.”

Luis Rivera: ‘It proved to be a space for great professional and personal growth for me. The difficulty behind solving the problems and creating something new that t underscored the need for teamwork in all aspects of science, and helped me grow closer to people I call my friends today.’ 

Cesar Quinones-Martinez: ‘The Arecibo global Competition consisted of 3 stages to highlight important stages of making the message: interpretation, decoding a received message, and finally writing our New Arecibo Message. The first stage showed how clever message design can contain a lot of information about the subject material. Imagine a pixelated image of a human sent at a certain frequency. How do you figure out the human’s average height? The key is the frequency, which corresponds to a specific wavelength so that by counting the pixels, you can approximately obtain the height.

“However, is that all the information you can extract from the image? Knowing the size of the pixels, you can figure out the ratio of the head to the arms, legs, and abdomen, communicating more about humans without added complexity. The second stage gave us a scenario with a received message that we needed to decode. The team regularly pitched different ideas on what aspects of the signal were important to decode, which was useful to the design of the new Arecibo Message in the final stage. The competition was a great exercise in thinking outside the box and looking at different perspectives, showing the nuance of communicating efficiently when the turnaround time can be centuries.’

Aerial view of the damage to the Arecibo Observatory following the collapse of the telescope platform on December 1st, 2020. Photo courtesy of Deborah Martorell. The Last Arecibo Message

Lizmarie Mateo Roubert: “The content of the Last Arecibo Message contains information about humanity’s knowledge of mathematics, science, and astronomy. The first two sections include the numbers from 1 to 10 and the arithmetic symbols including the equal sign. We included mathematical and physical constants such as pi, the Euler constant, the speed of light, the Planck constant, and the Stefan-Boltzmann constant. Adding these constants in our message helps us with a variety of assumptions regarding the recipient’s understanding of the universe..” 

Germán Vázquez: “We also wanted to share astronomical aspects of our galaxy, solar system, and earth-moon system to pinpoint our location in the universe. The image of the Milky Way Galaxy is presented (up to scale) with the distance from the Galactic center to our solar system.

“The Arecibo Message, sent in 1974, served as a direct inspiration for the next section of our message, our Solar System. However, we wanted to enhance some aspects to make it more descriptive and accurate. We included our Moon and Saturn’s rings, enhanced the sizes of the gas giants, and excluded Pluto, which is now considered a dwarf planet.

“The Earth-Moon system was also implemented in our message, considering the impact our natural satellite has had in shaping humanity, influencing our calendars, producing ocean tides, and understanding celestial mechanics. Lastly, our depiction of a human being, the average height, and the population in 2020 were also included, alluding to the original message.”

Kelby Palencia-Torres: “The purpose of the message is to continue the legacy of the Arecibo Observatory and the Original message by Frank Drake. Our message sums up humanity’s curiosity and wanting to explore the universe together.”

Q: “What significance could this have for the ongoing debate concerning METI?“

Kelby Palencia-Torres: “The message we constructed for the Arecibo Message Global Challenge was to commemorate and demonstrate the importance the original had. Currently, our message does not have plans to be transmitted. But it showcases the innate curiosity and feelings we have to see if we are alone. Our message will go to the list of messages built with METI purposes and show the interest in taking the first step in communicating with other intelligence.

“One of the assumptions we use in our paper can also back up METI since other civilizations with similar capabilities to our civilization will face the same constraints as SETI. Whoever listens will need resources, energy, and telescope time to look for techno signatures in their sky. Assuming that other civilizations have a greater technological feat than us, it would mean giving access to resources and a really big and sensitive radio telescope to a being from this advanced civilization to search for techno signatures, and it all would be reduced to be lucky enough to be looking at the right moment and time to receive a one time signal that is not continuous such like the original Arecibo message or the wow signal.”

Further Reading: arXiv

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Despite 90 years of research, the nature and influence of Dark Matter continue to elude astronomers and cosmologists. First proposed in the 1960s to explain the rotational curves of galaxies, this invisible mass does not interact with normal matter (except through gravity) and accounts for 85% of the total mass in the Universe. It is also a vital component in the most widely accepted cosmological model of the Universe, the Lambda Cold Dark Matter (LCDM) model. However, according to new research, the hunt for DM could be over as soon as a nearby star goes supernova.

Currently, the axion is considered the most likely candidate for DM, a hypothetical low-mass particle proposed in the 1970s to resolve problems in quantum theory. There has also been considerable research into how astronomers could detect axions by observing neutron stars and objects with powerful magnetic fields. In a recent study supported by the U.S. Department of Energy, a team of astrophysicists at the University of California Berkeley argued that axions could be discovered within seconds of detecting gamma rays from a nearby supernova explosion.

The study was conducted by researchers at the Berkeley Center for Theoretical Physics (BCTP) and a member of the Lawrence Berkeley National Laboratory’s (LBNL) Theoretical Physics Group. The paper that describes their findings was published on November 19th in the journal Physical Review Letters. As they argue, axions would be produced in copious quantities during the first 10 seconds after a massive star undergoes core collapse and becomes a neutron star. These axions would then escape and be transformed into high-energy gamma rays in the star’s intense magnetic field.

For decades, the search for Dark Matter focused on MAssive Compact Halo Objects (MACHOs). When they failed to materialize, physicists began to consider Weakly Interacting Massive Particles (WIMPs) as the most likely candidate but also failed to find anything tangible. This led to axions becoming the most widely accepted candidate, an elementary particle that fits within the Standard Model of Particle Physics and resolves several unresolved questions in Quantum Mechanics – including a Theory of Everything (ToE).

The strongest candidate for axions is the quantum chromodynamics (QCD) axion, which theoretically interacts with all matter, though weakly. As previous research has shown, axions will occasionally turn into photons in the presence of a strong magnetic field that can be detected. However, such detections would be very challenging since it would require that the supernova be nearby (within the Milky Way or one of its satellite galaxies). In addition, observable supernovae are rare, occurring once every few decades.

The last time astronomers observed this phenomenon was in 1987 when a Type II supernova (SN1987A) appeared suddenly in the Large Magellanic Cloud (LMC), roughly 168,000 light-years from Earth. At the time, NASA’s Solar Maximum Mission (SMM) was observing the LMC but wasn’t sensitive enough to detect the predicted intensity of gamma rays. Benjamin Safdi, a UC Berkeley associate professor of physics and senior author of a paper, explained in a recent UC Berkeley News statement:

“If we were to see a supernova, like supernova 1987A, with a modern gamma-ray telescope, we would be able to detect or rule out this QCD axion, this most interesting axion, across much of its parameter space — essentially the entire parameter space that cannot be probed in the laboratory, and much of the parameter space that can be probed in the laboratory, too. And it would all happen within 10 seconds.”

Illustration of NASA’s Fermi Gamma-ray Space Telescope at work. Credit: NASA GSFC

Through a series of supercomputer simulations that used SN1987A to constrain higher mass axions, Safdi and his colleagues determined that Type II supernovae simultaneously produce bursts of gamma rays and neutrinos. They further noted that the gamma rays produced would depend on the axions’ mass and only last 10 seconds after the neutron star forms. After that, the production rate would drop dramatically. This means a gamma-ray space telescope must be pointed toward the supernova at precisely the right time.

The Fermi Gamma-ray Space Telescope is currently the only observatory capable of detecting cosmic gamma-ray sources. Based on its field of view, scientists estimate that Fermi would have about a one-in-ten chance of spotting a supernova. To that end, the team proposes that we create a next-generation gamma-ray telescope known as the GALactic AXion Instrument for Supernova (GALAXIS). Said Safdi:

“This has really led us to thinking about neutron stars as optimal targets for searching for axions as axion laboratories. Neutron stars have a lot of things going for them. They are extremely hot objects. They also host very strong magnetic fields. The strongest magnetic fields in our universe are found around neutron stars, such as magnetars, which have magnetic fields tens of billions of times stronger than anything we can build in the laboratory. That helps convert these axions into observable signals.”

As they note, a single detection of gamma rays would pinpoint the mass of an axion over a huge range of theoretical masses and allow for laboratory experiments to refocus their efforts on confirming this mass. Even a lack of detection would mean that scientists could eliminate a large range of potential masses for the axion, which would narrow the search for Dark Matter considerably. In the meantime, Safdi and his colleagues hope the Fermi telescope will catch a lucky break.

“The best-case scenario for axions is Fermi catches a supernova,” he added. “It’s just that the chance of that is small. But if Fermi saw it, we’d be able to measure its mass. We’d be able to measure its interaction strength. We’d be able to determine everything we need to know about the axion and incredibly confident in the signal because there’s no ordinary matter which could create such an event.”

Further Reading: UC Berkeley News, Physical Review Letters

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Astronomers have just found one of the youngest planets ever. At only 3 million years old, planet TIDYE-1b (also known as IRAS 04125+2902 b) is practically in its infancy. By comparison, Earth is 4.5 billion years old: that’s 1500 times older. The discovery of a planet this young can teach scientists a lot about the early stages of planet formation, and the peculiarities of this particular one have scientists re-evaluating their models of planetary birth.

“Astronomy helps us explore our place in the Universe — where we came from and where we might be going. Discovering planets like this one allows us to look back in time, catching a glimpse of planetary formation as it happens,” said Madyson Barber, lead author of a new paper and graduate student at UNC-Chapel Hill.

Barber discovered TIDYE-1b using the transit method, where a planet passes in front of its star, dimming the light and revealing itself to the observer – in this case, NASA’s TESS telescope. Previously, more than a dozen young planets in the 10-40 million-year-old range have been found via transit, but TIDYE-1b surpasses them all.

It’s a rare find because, under normal circumstances, such young planets are usually obscured by gas and dust that make up the ‘protoplanetary disc’, a debris field orbiting a star like a ring, out of which new planets are built.

“Planets typically form from a flat disk of dust and gas, which is why planets in our Solar System are aligned in a ‘pancake-flat’ arrangement,” explains Andrew Mann, associate professor at UNC-Chapel Hill. “But here, the disk is tilted, misaligned with both the planet and its star — a surprising twist that challenges our current understanding of how planets form.” 

Since TIDYE-1b orbits its star at a different angle than the main protoplanetary disc, it was visible despite its youth. It can often take more than five million years for such a disc to clear out in a young star system, so this was a lucky break without which the astronomers would not have been able to see the planet.

The planet is very close to its star, orbiting around it about once every nine days. The researchers believe it is a young example of what will someday become a ‘super-Earth or a ‘sub-Neptune, a planet type missing in our solar system but which seems common in the wider Milky Way galaxy. TIDYE-1b is not as dense as the Earth is, but it is about 11 times larger in diameter.

The discovery provides conclusive evidence that planets can form earlier than previously known – the lack of examples of planets younger than 10 million years found so far is not because they don’t exist. It’s just because they tend to be hidden from view.

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Earth and Mars were very similar in their youth. Four billion years ago, both planets had vast, warm seas. But while Earth retained its oceans, the waters of Mars evaporated away or froze beneath its dusty surface. Exactly why these two worlds took such divergent paths is unclear, though it may lie in the origins of their water.

Based on geological studies, we know that Earth’s water cycle seemed to have stabilized early. From about 4.5 billion years ago to today, water has had a stable presence on Earth. For Mars, things are less clear. Clay minerals cover about 45% of the Martian surface and date to what is known as the Noachian period, which ranges from 4.1 to 3.7 billion years ago. We also see evidence of water flows from 3.7 to 3.0 billion years ago, in what’s known as the Hesperian period. During the Amazonian period, which dates from 3 billion years ago to today, Mars seems to have been mostly dry. We have little evidence of the earliest period of Mars, known as the pre-Noachian. But a new study peels back the Martian ages to give us a glimpse of the first epoch of Mars, and it comes from a Martian meteorite known as Black Beauty.

Black Beauty, or NWA 7034, is a Martian meteorite thought to have formed at a time when the Red Planet harbored a magnetic field. Credit: C Agee, Institute of Meteoritics, UNM; NASA

There are about 200 meteorites known to have come from Mars, and they are currently the only physical samples of Mars we have on Earth. One of the larger meteorites, Northwest Africa 7034, was discovered in Western Sahara in 2011 and is nicknamed “Black Beauty” because of its rich black coloring. It’s made of material that’s about 4.4 billion years old and contains more water than any other Martian meteorite. But since it was only ejected from Mars 1.5 billion years ago, it is difficult to determine whether Black Beauty formed in a wet environment or if it gained water during the Noachian or Hesperian period.

This new study doesn’t focus on Black Beauty as a whole, but rather on small crystals of zircon embedded within it. These crystals can be dated to 4.48–4.43 billion years, meaning they formed in the Pre-Noachian period. What’s interesting is that the crystals have layers of iron, aluminum, and sodium in a pattern known as oscillatory zoning. Since zircon is igneous in origin, this kind of banding is almost unheard of in zircon crystals. On Earth, there is only one place where such a pattern occurs, which is in hydrothermal geysers such as those found in Yellowstone National Park.

The presence of these crystals in Black Beauty proves not only that Mars was wet during the Pre-Noachian period, but that it was geologically active with warm thermal vents. Similar vents on Earth may have triggered the formation of life on our world. Whether life ever existed on Mars is still an unanswered question, but it is clear that the conditions for life on Mars did exist in its earliest history.

Reference: Gillespie, Jack, et al. “Zircon trace element evidence for early hydrothermal activity on Mars.” Science Advances 110.47 (2024)

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Dark matter made out of axions may have the power to make space-time ring like a bell, but only if it is able to steal energy from black holes, according to new research. 

An intriguing possibility for a candidate for the mysterious dark matter is that it might be an axion. Originally predicted to exist decades ago to explain some strange properties of the strong nuclear force, axions have yet to be detected in the laboratory or in any experiments. However, this elusiveness would make them a perfect candidate for dark matter, since by definition dark matter hardly if ever interacts with normal matter.

If the dark matter is an axion, or of a kind of particle related to the axion, then it would have very strange properties. It would be the lightest particle ever known, in some models no bigger than a billionth the mass of the electron. The incredible lightweight nature of this particle means that it would behave in very strange ways in the cosmos. It would be so light that its quantum wave nature would manifest on very large scales, meaning that it would tend to act more like a wave than a particle.

One of the ways this wave nature would manifest would be around rotating black holes. Through a process known as super-radiance, this kind of dark matter could steal angular momentum from the black hole. This would prevent the dark matter from falling through the event horizon, and instead it would pile up around the black hole like an invisible shroud.

But once no more new energy could be extracted from the black hole, the dark matter would evaporate away. In the process, according to new research, the dark matter would ring space-time like a bell, sending out an enormous amount of gravitational waves.

These gravitational waves would have a distinct signature from the ones known through black hole mergers. And even though they would be far weaker, they would be in the frequency ranges of detectability for existing and planned gravitational wave observatories.

The researchers proposed that we comb through existing data to hunt for any potential signatures of this kind of dark matter collecting around black holes. And if we don’t find what we looking for, we could still fine-tune upcoming experiments to hunt for this surprising signal.

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Most of the time the Sun is pretty well-mannered, but occasionally it’s downright unruly. It sometimes throws extremely energetic tantrums. During these events, a solar flare or a shock wave from a coronal mass ejection (CME) accelerates protons to extremely high velocities. These are called Solar Particle Events or Solar Proton Events (SPEs).

However, the exact timing of these events can be difficult to ascertain. New research has determined the date of one of the most powerful SPEs to strike Earth during the Holocene.

No one alive today has witnessed the Sun’s extreme power. But ancient people did. In the last 14,500 years, there have been several solar storms and SPEs powerful enough to damage living things and create aurorae at middle latitudes, even at the equator. Understanding the timing of these ancient events is a key part of understanding the Sun.

Powerful outbursts from the Sun are becoming a more significant threat as we expand our presence in space. They can damage satellites and pose a radiation threat to astronauts. Even the Earth’s surface isn’t safe from the most powerful SPEs which can knock out technological infrastructure like power grids and communications networks.

“If they happened today, they would have cataclysmic effects on communication technology.”

Irina Panyushkina, University of Arizona

The Sun’s most powerful outbursts seem to occur during solar maximum, the period of greatest activity during the Sun’s 11-year cycle. But there’s some uncertainty, and since SPEs can be so damaging, there’s a need to understand them better, beginning with their timing.

Only six SPEs have left their mark on Earth in about the last 14,500 years. Historical accounts can open a window into the timing of ancient SPEs, but they’re plagued by inaccuracies and inconsistencies. Fortunately, these natural events leave a trace in the natural world.

These solar outbursts create what are called Miyaki Events after the Japanese physicist Fusa Miyake. Miyake discovered that they create a sharp rise in cosmogenic isotopes due to increased cosmic rays striking Earth’s upper atmosphere. The events create carbon-14 (14C), a radioactive isotope that is present in tree rings. The events also create other isotopes like Beryllium-10 (10Be)and Chlorine-36 (36Cl) that are present in ice cores.

In new research published in Nature Communications Earth and Environment, researchers pinpointed the timing of the last SPE to strike Earth. It’s titled “The timing of the ca-660 BCE Miyake solar-proton event constrained to between 664 and 663 BCE.” The lead author is Irina Panyushkina from the University of Arizona’s Laboratory for Tree-Ring Research.

There have been several Miyake events depending on how they’re defined.

“Thanks to radiocarbon in tree-rings, we now know that six Miyake events happened over the last 14,500 years,” Panyushkina said. “If they happened today, they would have cataclysmic effects on communication technology.”

Carbon-14 continuously forms in Earth’s atmosphere because of cosmic radiation. In the atmosphere, it combines with oxygen to form CO2. “After a few months, carbon-14 will have traveled from the stratosphere to the lower atmosphere, where it is taken up by trees and becomes part of the wood as they grow,” said lead author Panyushkina.

During a Miyake event, the amount of carbon-14 spikes, and that spike is reflected in tree rings. There have been several of these events, depending on how they’re defined, and several more awaiting more rigorous confirmation. There rate of occurrence is poorly understood, but the data we have shows that they occur every 400 to 2400 years. One of them occurred around 660 BCE, and that event is the subject of much research.

“The precise positioning of a SPE in real time is extremely important for the parameterization of solar activity and forecasts,” the authors write in their research. “Notably, one of the recently confirmed SPE events does not have an exact calendar date. Multiple radionuclide evidence of an extreme SPE (or ME) event ca. 2610 BP (before 1950) more commonly referenced as ca. 660 BCE, was confirmed with high-resolution 10BE records of three ice cores from Greenland in 2019.”

The circa 660 Miyake event is different from the others. “However, the ca. 660 BCE ME has an unusual structure that is different from the short-term rapid increases in radionuclide production observed at 774–775 CE and 993–994 CE. One proposed explanation is the possible occurrence of consecutive SEPs over up to three years,” the authors explain in their research. If Miyake events can occur in such rapid succession, we need to know about it, for obvious reasons.

In this new research, the team analyzed tree rings for 14C content to generate an accurate date for the ca-660 BCE Miyake event. They focused on larch trees in arctic-alpine biomes, one in the Altai mountains and the other in the Yamal Peninsula. In these regions, larch trees are more sensitive to atmospheric changes and have clearer 14C spikes.

This figure from the research explains some of the research into the ca. 660 BCE Miyake event. a) shows variations of Carbon-14 concentrations measured in tree rings, and b) shows the locations of the samples. Image Credit: Panyushkina et al. 2024.

Panyushkina and her co-researchers examined tree rings from ancient samples, including trees buried in mud and sediment and timbers excavated during archaeological digs and measured the Carbon-14 content. Next, they correlated their findings with other research into Beryllium-10 found in ice sheets and glaciers. Beryllium-10 is also created during Miyake events. It isn’t absorbed by trees, but is deposited in ice.

“If ice cores from both the North Pole and South Pole show a spike in the isotope beryllium-10 for a particular year corresponding to increased radiocarbon in tree-rings, we know there was a solar storm,” Panyushkina said.

This sounds like a nice tidy way to determine the dates of Miyake events, but it’s not so easy. Researchers have struggled to find a pattern. Tree rings are clearly marked by growing seasons, but ice cores are not. There’s also a lag time between the creation of Carbon-14 in the atmosphere and its presence in trees, and in ice. Different trees also absorb the carbon at different times and rates, and they also store and recycle the carbon, which can influence how they serve as recorders of atmospheric CO2. These and other challenges mean that conclusions don’t jump out of the data.

But this research still has value, even if it isn’t the silver bullet when it comes to predicting these powerful solar events. The issue with the 660 BCE event is its complexity. It seems to have several spikes and declines in a short period, suggesting more complex solar behaviour than a simple single-spike storm.

“Our new 14C data defined the two-pulse duration, considerable magnitude, and the precise date of what was previously described as the event ‘around 660 BCE’,” the authors write. “We showed that the double pulse of cosmic radiation during 664—663 BCE produced a nontypical pattern of ME cosmogenic isotope production recorded at multiple locations in northern Eurasia.”

This figure from the study illustrates some of the complexity that makes pinning down the exact date of the circa 660 BCE Miyake event difficult. Different types of trees in different locations have different spikes in Carbon-14. PDF stands for probability distribution function. Image Credit: Panyushkina et al. 2024.

“The impact appears as a 2–3 year rise of Carbon-14 concentrations tailed by a 2–3-year peak (or plateau) before the signal decays,” the authors write. The Carbon-14 production in 664 BCE was 3.5 and 4.8 times greater than the 11-yr average.

What does it all mean?

There’s a lot of complexity. Different trees absorb carbon differently, the stratosphere and troposphere mix differently at different times, and growing seasons can vary significantly. “Finally, the double pulse of the 664–663 BCE ME onset and the prolonged waning of the 14C spike signal implies possible uncertainties complicating the use of this spike signal for single-year dating of archeological timbers and occurrences,” the researchers explain in their conclusion.

However, one thing is clear in all of the data. The Sun has blasted Earth with extreme SPEs in the past that are much more powerful than anything in modern time. “Extreme proton events that are hundreds or thousands of times stronger than those of modern instrumental observations may recur on the timescale of hundreds of years,” the authors write in their conclusion.

Ultimately, the tree rings can shed light on how powerful these solar storms are, but they’re not exact when it comes to dating them.

“Tree-rings give us an idea of the magnitude of these massive storms, but we can’t detect any type of pattern, so it is unlikely we’ll ever be able to predict when such an event is going to happen,” Panyushkina said. “Still, we believe our paper will transform how we search and understand the carbon-14 spike signal of extreme solar proton events in tree rings.”

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Earth and Mars are the only two rocky planets in the solar system to have moons. Based on lunar rock samples and computer simulations, we are fairly certain that our Moon is the result of an early collision between Earth and a Mars-sized protoplanet called Theia. Since we don’t have rock samples from either Martian moon, the origins of Deimos and Phobos are less clear. There are two popular models, but new computer simulations point to a compromise solution.

Observations of Deimos and Phobos show that they resemble small asteroids. This is consistent with the idea that the Martian moons were asteroids captured by Mars in its early history. The problem with this idea is that Mars is a small planet with less gravitational pull than Earth or Venus, which have no captured moons. It would be difficult for Mars to capture even one small asteroid, much less two. And captured moons would tend to have more elliptical orbits, not the circular ones of Deimos and Phobos.

An alternative model argues that the Martian moons are the result of an early collision similar to that of Earth and Theia. In this model, an asteroid or comet with about 3% of the mass of Mars impacted the planet. It would not be large enough to have fragmented Mars, but it would have created a large debris ring out of which the two moons could have formed. This would explain the more circular orbits, but the difficulty is that debris rings would tend to form close to the planet. While Phobos, the larger Martian moon, orbits close to Mars, Deimos does not.

This new model proposes an interesting middle way. Rather than an impact or direct capture, the authors propose a near miss by a large asteroid. If an asteroid passed close enough to Mars, the tidal forces of the planet would rip the asteroid apart to create a string of fragments. Many of those fragments would be captured in elliptical orbits around Mars. As computer simulations show, the orbits would shift over time due to the small gravitational tugs of the Sun and other solar system bodies, eventually causing some of the fragments to collide. This would produce a debris ring similar to that of an impact event, but with a greater distance range, better able to account for both Phobos and Deimos.

While this new model appears to be better than the capture and impact models, the only way to resolve this mystery will be to study samples from the Martian moons themselves. Fortunately, in 2026 the Mars Moons eXploration mission (MMX) will launch. It will explore both moons and gather samples from Phobos. So we should finally understand the origin of these enigmatic companions of the Red Planet.

Reference: Kegerreis, Jacob A., et al. “Origin of Mars’s moons by disruptive partial capture of an asteroid.“ Icarus 425 (2025): 116337.

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The largest magnetic fields in the universe may have found themselves charged up when the first stars began to shine, according to new research.

Magnetic fields are everywhere in the universe, but most of those magnetic fields arise from a process called a dynamo mechanism. These are any physical process that can take magnetic fields and stretch them out, twist them up, and fold them over on each other to make them stronger. For example, dynamo processes in the core of the Earth give us our powerful magnetic field.

But astronomers also find magnetic fields at the very largest of scales, with weak but persistent fields spanning across galaxies or even galaxy clusters. These fields are usually no stronger than a millionth the strength of the Earth’s, but they can reach for millions of light years in length.

Astronomers have long wondered what powered the creation of these magnetic fields, and a new study has put forward and intriguing hypothesis.

When our Universe was only a few hundred million years old, the first stars began to shine. They quickly died and seeded the universe with bits and pieces of heavier elements, creating the first grains of dust in the process.

When the next generation of stars came online their powerful radiation shown through all the gas and dust surrounding them. That radiation was so powerful that it could literally push on the dust grains.

The dust grains were electrically charged, and once they started moving it created a weak but very large-scale electrical current. An electrical current naturally gives rise to a magnetic field. At first this magnetic field was uniform, but as time went on the dust grains would clump here and there leading to irregularities that would start to mix up entangle the magnetic field.

These magnetic fields were incredibly weak, no more than a billionth the strength of the Earth. But they were very large, the researchers predict, at least a few thousand light-years in size. These are the perfect conditions to allow for dynamo mechanisms to begin to amplify them and stretch them out to their present-day size.

The scenario painted by the researchers is essentially a battery made of dust surrounding newborn stars stretching for thousands of light-years in the early universe. It’s a fascinating possibility, and the researchers propose that the next step is to investigate how the evolution of these fields unfold in detailed simulations of cosmic evolution, and compare those results to observations.

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Like a performer preparing for their big finale, a distant star is shedding its outer layers and preparing to explode as a supernova.

Astronomers have been observing the huge star, named WOH G64, since its discovery in the 1970s. It’s one of the largest known stars, and also one of the most luminous and massive red supergiants (RSGs). The star is surrounded by an envelope of expelled star-stuff, which could indicate it’s getting ready to explode.

WOH G64 isn’t in the Milky Way; it’s in the Large Magellanic Cloud (LMC), the Milky Way’s largest satellite galaxy. Getting these detailed image is quite a feat for the ESO’s Very Large Telescope Interferometer. It’s also quite an accomplishment for the team of scientists behind the image.

They’ve published their images and the results of their observations of the star in the journal Astronomy and Astrophysics. Their research is titled “Imaging the innermost circumstellar environment of the red supergiant WOH G64 in the Large Magellanic Cloud.” The lead author is Keiichi Ohnaka, an astrophysicist from Universidad Andrés Bello in Chile.

“This star is one of the most extreme of its kind, and any drastic change may bring it closer to an explosive end.”

Jacco van Loon, study co-author, Keele Observatory

“Significant mass loss in the red supergiant (RSG) phase is of great importance for the evolution of massive stars before they end their life in a supernova (SN) explosion,” the researchers write in their paper. Understanding the progenitors to supernovae (SNe) is important because of the role they play in the Universe. These massive stars forge heavy elements through nucleosynthesis then spread them out into their surroundings when they explode. These heavy elements make rocky planets possible. SNe shockwaves can also compress gas in their vicinities, which can trigger the birth of new stars. Better images of stars approaching their explosive ends help astronomers understand them better.

“For the first time, we have succeeded in taking a zoomed-in image of a dying star in a galaxy outside our own Milky Way,” lead author Ohnaka said.

WOH G64 (WOH hereafter) is a whopping 160,000 light-years away. Even though the red supergiant is a behemoth that’s 2,000 times larger than the Sun, that’s an enormous distance. It’s all because of the VLTI and one of its newer instruments, called GRAVITY. It’s a powerful instrument that was installed on the VLTI in 2015.

When Ohnaka and his colleagues saw the images, they were buoyed with excitement. The images show a cocoon of dust surrounding the star, evidence that it’s convulsed and shed some of its outer layers.

“We discovered an egg-shaped cocoon closely surrounding the star,” said lead author Ohnaka. “We are excited because this may be related to the drastic ejection of material from the dying star before a supernova explosion.”

This artist’s reconstruction shows the star’s main features. The star is surrounded by an egg-shaped dust cocoon, with a wider ring or torus of dust. Astronomers are less certain about the shape and size of the outer ring, which requires more observations for clarity. Image Credit: ESO/L. Calçada

Ohnaka and his colleagues have been observing WOH for a long time, but had to wait for better instruments to get a closer look.

Among other things, they noticed that the star has become dimmer over the last decade.

Gerd Weigelt is an astronomy professor at the Max Planck Institute for Radio Astronomy and a co-author of the research. “We have found that the star has been experiencing a significant change in the last 10 years, providing us with a rare opportunity to witness a star’s life in real time,” Weigelt said. In their final life stages, red supergiants like WOH G64 shed their outer layers of gas and dust in a process that can last thousands of years.

Jacco van Loon, the director of the Keele Observatory at Keele University in the UK has been observing WOH since the 1990s. “This star is one of the most extreme of its kind, and any drastic change may bring it closer to an explosive end,” Keele said.

With the more limited data available in the past, Ohnaka modelled what the dust environment might look like. Those models and observations predicted a different shape than the GRAVITY images reveal.

The images show an elongated, compact emission region in near-infrared (NIR) surrounding the star. This suggests that hot new dust has formed near the star, which helps obscure the star itself. The star’s NIR continuum has shifted in the last decade, which also supports the new dust hypothesis. Earlier images from before 2003 show more hydrogen absorption than recent images.

Other observations of RSG stars also show that their circumstellar environments aren’t spherical. For example, dust surrounding the remnant of SN1987A is also not spherical. Astrophysicists think that this dust was shed by SN1987A’s progenitor star before it evolved into a blue supergiant and exploded.

The elongated, cocoon shape of the emissions has two potential explanations. “The elongated emission may be due to a bipolar outflow along the axis of the dust torus,” the authors explain. “Alternatively, the elongation may be caused by the interaction with an unseen companion.”

This reconstructed GRAVITY image of WOH G64 is from the research and clearly shows the elongated, cocoon shape. Image Credit: Ohnaka et al. 2024.

The non-spherical structures are common, and researchers want to understand this phenomenon better. “Given the high multiplicity rate among massive stars, the asymmetric, enhanced mass loss in the RSG phase, which can be driven by binary interaction, is essential not only for better understanding the evolution of massive stars but also for interpreting early-phase SN spectra,” the authors explain.

Unfortunately, observing WOH is becoming more difficult. The dust is obscuring the star. “The formation of new hot dust also means that the central star is now more obscured than the epochs before 2009,” the authors explain, and if the star keeps shedding material, the star will become dimmer.

But new instruments might help. GRAVITY’s successor, GRAVITY+ is being rolled out incrementally and will be completed in 2026.

“Similar follow-up observations with ESO instruments will be important for understanding what is going on in the star,” concluded Ohnaka.

WOH G64 is getting ready to explode, but that doesn’t mean it’s imminent in terms of human lifespans. Nobody alive today will witness the explosion. However, in stellar terms, the star’s death could be imminent.

Maybe our distant descendants, if we have any, will witness it.

The post The First Close-Up Picture of Star Outside the Milky Way appeared first on Universe Today.

For a little over a month now, the Earth has been joined by a new ‘mini-moon.’ The object is an asteroid that has been temporarily accompanying Earth on its journey around the Sun. By 25th November it will have departed but before then, astronomers across the world have been turning their telescopes to study it. A new paper of 2024 PT5 reveals its basaltic nature – similar to volcanic rocks on Earth – with a composition that makes it similar to lunar material. There have been many close encounters to Earth allowing many of its secrets to be unveiled.

The Moon is perhaps one of the most well known astronomical objects. It’s Earth’s only permanent natural satellite and has been in orbit since early in the planet’s history. It lies approximately 384,400 kilometres away and has played a crucial part in stabilising are axial tilt and regulating the climate and seasons. In addition to the Moon we are occasionally joined by asteroids that briefly orbit around the Earth before continuing their journey through the Solar System. 

The partial lunar eclipse from October 2023 as seen from Oxfordshire UK. Credit: Mary McIntyre FRAS.

2024 PT5 is a small asteroid that has served as a temporary “mini-moon” for Earth, orbiting near the planet for about six weeks. Analysis has revealed that the asteroid spins rapidly, completing one full rotation in under an hour and measures no more than 15 metres across. While it will leave Earth’s vicinity in just a few days, its brief presence has offered valuable insight and data on the properties of near-Earth objects.

Space agencies like NASA and ESA are both exploring commercial space operations to support the growing global space economy. Exploring and mining asteroids is an activity that is well suited to this endeavour. Asteroids like 2024 PT5 which is in close proximity to Earth is well suited to this. The paper that has been published in Astronomy & Astrophysics and was authored by R. de la Fuente Marcos and a team of Spanish astronomers.

The asteroid Dimorphos was captured by NASA’s DART mission just two seconds before the spacecraft struck its surface on Sept. 26, 2022. Observations of the asteroid before and after impact suggest it is a loosely packed “rubble pile” object. Credit: NASA/JHUAPL

The study focussed attention on changes to the short-term orbital properties and used N-body simulations (a technique to simulate a dynamic system under other physical forces such as the force of gravity.) They also explored the spectral class of the asteroid from reflectance spectra analysis obtained with the OSIRIS spectrograph and assessed its rotational properties.

The team confirmed that 2024 PT5 is a natural object (thankfully) that has a spectra which is consisted with the so called Sv-type asteroid, similar to breccia found in the Lunar mare. Assessment of its rotational properties revealed it is completing one rotation in less than an hour. They could not rule out whether the asteroid was tumbling in an erratic fashion, further analysis is needed. Finally through astrometric observations the team concluded that the orbits of 2024 PT5 and 2022 NX1 (another near Earth asteroid which is just 10 metres across) are very similar. 

Both ESA and NASA now consider a cost-effective strategy for NEO missions essential with a focus on small body science and planetary defence. The approach includes reusing and active missions and identifying accessible objects like 2022 NX1 and 2024 PT5 using ground-based observatories.  

Source : Basaltic mini-moon: Characterizing 2024 PT5 with the 10.4 m Gran Telescopio Canarias and the Two-meter Twin Telescope

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Despite decades of study, black holes are still one of the most puzzling objects in the Universe. As we know from Einstein’s Theory of General Relativity, the gravitational force of these stellar remnants alters the curvature of spacetime around them. This causes gas, dust, and even photons (light) in their vicinity to fall inwards and form disks that slowly accrete onto their faces, never to be seen again. However, astronomers have also noted that they can produce powerful jets that accelerate charged particles to close to the speed of light (aka. relativistic jets).

These jets lead to powerful gamma-ray bursts (GRBs), which have been observed with black holes that have powerful magnetic fields. However, where these magnetic fields come from has remained a mystery to astrophysicists for some time. According to new research led by scientists from the Flatiron Institute, the source of these fields may have finally been revealed. Based on a series of simulations they conducted that modeled the life cycle of stars from birth to collapse, they found that black holes inherit their magnetic fields from the parent stars themselves.

The research was led by Ore Gottlieb, a Research Fellow from the Theoretical High Energy Astrophysics (THEA) group at the Flatiron Institute’s Center for Computational Astrophysics (CCA) and Columbia University’s Astrophysics Laboratory. He was joined by colleagues from the CCA and CAL and researchers from the University of Arizona, the Steward Observatory, and Princeton University. The paper that details their findings was published on November 18th in the Astrophysical Journal Letters.

Infographic explaining how black holes inherit their magnetism. Credit: Lucy Reading-Ikkanda / Simons Foundation

Black holes form from the collapse of proto-neutron stars, which are essentially what remains after massive stars have blown off their outer layers in a supernova explosion. While there have been a few theories about where black holes get their magnetism, none could account for the power of black hole jets or GRBs. Through their simulations, the team initially planned to study outflows from black holes, including the jets that produce GRBs. However, as Gottlieb’s explained in a Simons Foundation press release, the team ran into a problem with the models:

“We were not sure how to model the behavior of these magnetic fields during the collapse of the neutron star to the black hole. So, this was a question that I started to think about for the first time. What had been thought to be the case is that the magnetic fields of collapsing stars are collapsing into the black hole. During this collapse, these magnetic field lines are made stronger as they are compressed, so the density of the magnetic fields become higher.”

The only problem with this theory is that the strong magnetic fields of neutron stars cause them to lose angular momentum (their rotation). Without this, the gas, plasma, and dust surrounding newly formed black holes will not form an accretion disk around them. This, in turn, would prevent black holes from producing the jets and gamma-ray bursts that astronomers have observed. This suggests that previous simulations of collapsing neutron stars didn’t provide a complete picture. Said Gottlieb:

“It appears to be mutually exclusive. You need two things for jets to form: a strong magnetic field and an accretion disk. But a magnetic field acquired by such compression won’t form an accretion disk, and if you reduce the magnetism to the point where the disk can form, then it’s not strong enough to produce the jets. Past simulations have only considered isolated neutron stars and isolated black holes, where all magnetism is lost during the collapse. However, we found that these neutron stars have accretion disks of their own, just like black holes. And so, the idea is that maybe an accretion disk can save the magnetic field of the neutron star. This way, a black hole will form with the same magnetic field lines that threaded the neutron star.”

3D rendering of a rapidly spinning black hole’s accretion disk and a resulting black hole-powered jet. Credit: Ore Gottlieb et al. (2024)

The team ran calculations for neutron stars collapsing to form black holes and found that, in most cases, the timescale for black hole disk formation is often shorter than that of the black hole losing its magnetism. In short, before a newly formed black hole swallows a proto-neutron star’s magnetic field, its magnetic field lines become anchored in the neutron star’s surrounding disk passes to the black hole. As Gottlieb characterized it:

“So the disk enables the black hole to inherit a magnetic field from its mother, the neutron star. What we are seeing is that as this black hole forms, the proto-neutron star’s surrounding disk will essentially pin its magnetic lines to the black hole. It’s very exciting to finally understand this fundamental property of black holes and how they power gamma ray bursts — the most luminous explosions in the universe.”

This discovery resolves the long-standing mystery of where black holes get their magnetic fields. It also presents astronomers with new opportunities to study relativistic jets and gamma-ray bursts, one of the most powerful phenomena in the Universe. If confirmed, these results suggest that forming an early accretion disk is the only thing needed for powerful jets to emerge. Gottlieb and his team are excited to test this theory with future observations.

Further Reading: Simons Foundation, Astrophysical Journal Letters

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74 million kilometres is a huge distance from which to observe something. But 74 million km isn’t such a big deal when the object is the Sun.

That’s how far away from the Sun the ESA/NASA Solar Orbiter was when it captured these new images.

The Solar Orbiter was launched in 2020 to investigate the Sun. It’s studying the mechanism behind the Sun’s solar wind, the complex dynamics of its magnetic field, and eruptions like solar flares and coronal mass ejections. That’s just a sampling of its science goals.

One item on the mission’s long list of objectives is high-resolution images of the Sun’s surface. For that, the spacecraft carries different imagers that operate in different wavelengths. This allows the spacecraft to almost peel back the Sun’s layers and uncover relationships between them.

The ESA has released four new images of the Sun, each one giving us a different look at our star: visible light, magnetic, plasma, and UV. These images were captured with the Polarimetric and Helioseismic Imager (PHI-German contribution) and Extreme Ultraviolet Imager (EUI-Belgian contribution) instruments in March 2023. Each image is a composite of 25 images, all captured on the same day. They’re the highest resolution images of the Sun ever taken.

The images are remarkable for their detail. This image shows sunspots, regions that are darker and cooler than their surroundings. They appear where magnetic field lines are concentrated. The magnetic flux inhibits convection. Image Credit: ESA

According to Daniel Müller, Solar Orbiter’s Project Scientist, the Sun’s magnetic field is key to understanding the star.

“The Sun’s magnetic field is key to understanding the dynamic nature of our home star from the smallest to the largest scales. These new high-resolution maps from Solar Orbiter’s PHI instrument show the beauty of the Sun’s surface magnetic field and flows in great detail. At the same time, they are crucial for inferring the magnetic field in the Sun’s hot corona, which our EUI instrument is imaging,” Müller said.

This magnetic map of the Sun from the Solar Orbiter shows how magnetic field lines and sunspots are correlated. Image Credit: ESA.

The Solar Orbiter’s PHI instrument also gives us a map of how plasma is moving around on the Sun’s surface. Blue regions are moving toward the Orbiter, while red regions are moving away.

The map of plasma movement clearly reflects the rotation of the Sun, with blue regions moving toward the orbiter and red regions moving away. However, it also shows how material is disoriented around the sunspots. Image Credit: ESA

The ultraviolet image of the Sun from the Solar Orbiter’s EUI instrument is probably the most visually stunning. It shows what’s happening above the photosphere, where glowing plasma extends out from sunspots. The plasma is superheated and follows the same magnetic lines that encourage the sunspots.

The Sun’s superheated plasma follow magnetic field lines and extends beyond the photosphere in the same regions the sunspots occur. Image Credit: ESA

The Solar Orbiter’s images are truly extraordinary. It’s easy to lose yourself in them, and to wonder about Life, the Universe, Nature, Evolution, How Everything Came to Be, and your own mortality in the face of it all.

Go ahead and lose yourself in these images for a while. The economy won’t grind to halt if you take a few moments. Image Credit: ESA

Now, back to your cubicle.

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