Tag: exploration

Astronomers discover a third galaxy devoid of dark matter

12:22 pm

Galaxy DF9
Click for original image.

The uncertainty of science: Using the Keck telescope in Hawaii, astronomers have discovered a galaxy that apparently has no dark matter, the third such galaxy discovered.

The galaxy, dubbed DF9, is shown to the right. It is part of a region that includes the other two galaxies with no dark matter, suggesting all three were formed in linked circumstances.

The team used Keck Observatory’s Keck Cosmic Web Imager (KCWI) to measure the motions of stars inside DF9 by analyzing the light emitted across different wavelengths. Those measurements revealed that DF9 has a mass of only about 100 million Suns, consistent entirely with the galaxy’s visible matter. If the galaxy contained a typical amount of dark matter, astronomers would expect it to be about 100 times more massive.

Dark matter was invented by astronomers in the 1960s to explain the inexplicable fast rotation of stars in the outer fringes of every galaxy they looked at, much faster than accounted for by the visible mass of each galaxy. That fast rotation suggested there was a lot more matter there that could not be seen, as much as one quarter of all mass according to some models. This unseen matter was then labeled “dark matter”, though even three-quarters of a century later it still remains undetected directly.

That these galaxies have no dark matter poses a difficult problem. At present the scientists are trying to come up with scenarios for creating these galaxies without it, but I suspect they will be hard-pressed to come up with any theory that convinces anyone.

I can’t help wondering if the problem isn’t the fast rotation of the stars, but the observations themselves. Maybe there is something we are missing or are unable to detect, because of the vast distances and faint nature of the light. Either way, dark matter, there or not, remains one of the big fundamental mysteries of cosmology.

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Curiosity sees smooth ground for the first time in years

11:01 am

June 12, 2026 Curiosity panorama
Click for full resolution version. Click here, here, and here for original images.

Overview mapd
Click for interactive map.

Cool image time! The panorama above was created from three pictures taken on June 12, 2026 by the left navigation camera on the Mars rover Curiosity (see here, here, and here). It shows the immediate ground uphill in front of the rover, which appears to be the smoothest ground that Curiosity has seen in about five years, since it entered the foothills at the base of Mount Sharp in 2021.

Since then the terrain has been routinely boulder strewn. In one case, the ground was so rocky and rough that the science team had to back off from their original plans and find a different route.

The panorama above shows something wholly different, a patch of relatively smooth ground with only a scattering of sharp rocks protruding periodically from below. This ground is likely the rover’s first taste of what the science team calls the “yardang unit”, the light colored hills in the lower right of the overview map to the right. For years that team has looked at those hills, wondering what it would be like to drive Curiosity on them. Their geology suggests a much softer terrain, sand shaped into dunes (yardangs) by the wind. The unknown was always whether the ground was structurally strong enough for the rover to traverse it.

It looks like they are about to get their first clue. Based on the panorama above, the ground appears very promising.

On the overview map, the blue dot marks Curiosity’s present position, with the red-dotted line is planned route and white-dotted line its actual travels. The yellow lines indicate approximately the area covered by the panorama.

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A galaxy as seen by Hubble and Webb

9:23 am

A galaxy seen by Hubble and Webb
Click for original image.

Cool image time. The picture to the right, cropped and reduced to post here, was taken on March 20, 2026 in a coordinated observations by both the Hubble and Webb space telescopes.

This March 20, 2026, image of Messier 64, or the Black Eye Galaxy, is a composite view from NASA’s Hubble Space Telescope and James Webb Space Telescope. It shows Messier 64 captured at near- and mid-infrared wavelengths by Webb, while Hubble’s image shows the galaxy in ultraviolet, visible, and near-infrared light.

Messier 64 is characterized by its bizarre internal motion. The gas in the outer regions of this spiral galaxy is rotating in the opposite direction from the gas and stars in its inner regions. This strange behavior may be the result of a merger between M64 and a satellite galaxy over a billion years ago.

The red in this image is dust, as the galaxy gets its nickname from the dark streak that wraps around its nucleus on its left side. In optical that streak is dark. Here Webb’s infrared view sees it in false color red.

READERS: It appears that it is a very slow news day today. Other than SpaceX’s IPO, which is on-going and too soon to post any reports, I can so far find nothing much of great significance on which to report.

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Parker makes 28th close fly-by of the Sun

12:48 pm

The overall flight plan for Parker
The overall flight plan for Parker. The green indicates
this most recent close approaches.

The Parker Solar Probe this past week successfully completed its 28th close fly-by of the Sun, zipping past its surface at a distance of only 3.8 million miles.

During this solar encounter, which started June 3 and ends Saturday, June 13, Parker’s four scientific instrument packages gathered data from inside the Sun’s atmosphere, or corona. Parker will begin returning detailed spacecraft telemetry on June 14, with science data transmission set to run from Wednesday, June 17 to Tuesday, June 30.

…Parker also equaled its record-setting speed of 430,000 mph — a mark that, like Parker’s distance to the Sun, was set during a close approach on Dec. 24, 2024, and matched during five flybys since, most recently on March 11. Parker will continue matching these speed and distance records during future flybys.

Engineers estimate the spacecraft’s heat shield experiences temperatures exceeding 1,700 degrees Fahrenheit with each close pass.

With each pass the spacecraft dives deep into the Sun’s corona and gathers data about it unobtainable from a distance. It is also gathering that data over time, as it first arrived in 2018, when the Sun was at its solar minimum with little sunspot activity. Since then it has ramped up to maximum and is presently thought to be on its way back down to minimum (though this still remains uncertain). Parker’s ability to gather data cross this timeline is invaluable for gaining a better understanding of the Sun’s behavior.

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Evidence of supernova remnant near the center of the Milky Way?

10:21 am

Supernova remnant near the Milky Way's center
Click for original image.

Using two X-ray space telescopes, astronomers now think they have detected evidence of a supernova remnant very close to the center of the Milky Way.

You can read their paper here [pdf]. The image to the right is a composite of optical (the stars), radio (the red nebula), and Chanda’s X-ray data (the blue nebula). From the press release:

The evidence for the new supernova remnant, located about 26,000 light-years from Earth, comes from X-ray data from Chandra and XMM-Newton. The X-ray data reveals a “blob” of X-ray emission [indicated by blue] that may come from the remains of a massive star that self-destructed as a supernova, buried within the larger cloud of expanding gas.

The location of this suspected supernova remnant in the image is [that blue region]. It is in bubble of gas [the surrounding larger and smaller red objects] that has had electrons stripped away from hydrogen — called an “H II region” — surrounding a massive, young star. If this is indeed a supernova remnant, then it is expanding at about two million miles per hour and is at least about 1,700 years old.

,..The long filaments seen in the radio image are caused by energetic particles travelling along magnetic fields that are mostly directed perpendicular to the plane of the galaxy.

According to the paper, this supernova remnant is found on the western edge of a vast energized gas cloud called the Central Molecular Zone (CMZ), 1,600 to 1,900 light years across, that spans the Milky Way’s center. The features seen in the image above are part of a feature on the CMZ’s western edge called Sagittarius C, which apparently has not been studied as much as other parts of the CMZ.

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A look back at a significant moment in human history: the first picture of the Moon’s far side

12:14 pm

The first picture ever taken of the Moon's far side, by Luna-3
Click for original image.

Today’s cool image is being posted not because of its beauty or high resolution, but because it was a significant first that shined a light on a mystery that had baffled all humanity since the first time a human being in Africa looked up and observed the Moon.

The picture to the right, reduced slightly and smoothed to remove some camera artifacts, was the first picture ever taken of the hidden far side of the Moon, captured by the Soviet Union’s Luna-3 probe on October 7, 1959, one day after it had passed less than 3,900 miles above the surface. As it moved away, it looked back, and took this picture from a distance of about 40,000 miles.

The picture ain’t what we are used to nowadays from space, but you need to put yourself back in time to truly appreciate it. For literally the entire history of humanity, this view had been hidden. Dreamers, philosophers, scientists, and ordinary people would look at the near side of the Moon almost nightly, but no one knew what was on the other side. Whole religious myths grew up about this unknown. Some science fiction writers of the 19th century fantasized there was air and water there and thus housed an alien civilization, purposely positioned so we couldn’t see it.

Suddenly, with this picture, that side was no longer hidden. This one Luna-3 picture showed humanity that the Moon’s far side was not much different than the near side, though much more cratered with fewer dark mare regions. It had no air or water. Nor were there alien civilizations.

But that age-old mystery was now solved. For those living in the 1950s, it was something of a revelation to see this picture. For those who came after, it is important to try to imagine the significance of that revelation. Suddenly, the mysteries of the universe were no longer unsolvable. Suddenly, we had the ability to solve them.

This picture, like all new knowledge, also brought with it new mysteries, based not on a hidden view but on real data and real questions. Now the goal was understand that data in order to solve the history of the Moon’s geology and how it fit into the formation of the Earth and the entire solar system. That endeavor is still on-going, with its solution not yet entirely in sight.

One last point: Though this picture is woefully inadequate compared to modern planetary images, it also carries a remarkable amount of good information that has since been confirmed by other spacecraft. To get an idea, compare it with a similar global view produced using Lunar Reconnaissance Orbiter (LRO)’s full dataset. The features match quite well, and a close look at the Luna 3 picture reveals many details not immediately evident that match well with the LRO image. The Russian engineers who made this happen should be rememberd and honored for their achievement.

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New Webb data suggests little red dots are supermassive black holes embedded in gas cloud

11:02 am

Little Red Dot GLIMPSE-17775
Little Red Dot GLIMPSE-17775

Using spectroscopic infrared data obtained by the Webb Space Telescope, astronomers now posit that the mysterious little red dots found by Webb in the very early universe are supermassive black holes embedded in a dense cloud of ionized gas.

The scientists focused Webb on the little red dot dubbed GLIMPSE-17775, shown to the right in a false color image produced by Webb’s near infrared camera. You can read their paper here [pdf].

The spectroscopic data collected by Webb contains multiple lines of evidence that support the interpretation that little red dot GLIMPSE-17775 is a black hole star: a rapidly accreting, or growing, black hole enveloped in a dense gas cocoon, which is reprocessing the light emitted from near the black hole and producing the features seen in the spectrum.

Among the 40-plus lines that the team detected in GLIMPSE-17775’s spectrum were various independent indicators that all align with the BH* scenario [the name the scientists use for this model]. For example, the team found that many of the spectral lines, such as hydrogen, oxygen, and helium, do not fit a simple model of a rotating gas cloud. Instead, the best fit model includes a broadening effect known as electron scattering, a telltale sign that a dense, layered gas cocoon is enshrouding this source.

The strength and ratios of certain lines to each other, most notably the 16 iron lines that compose what the team has dubbed an “iron forest” and certain oxygen lines, require a high-energy source to produce them, like a rapidly accreting black hole. Additionally, astronomers noted the fluorescence and absorption of helium in the spectrum, both of which individually suggest that there is a dense medium enveloping a powerful source.

The researchers claim this theory will work to explain all the other little red dots that Webb has detected in the early universe. They also claim it explains how the dots could be there so soon after the Big Bang, as they don’t have to be as supermassive as first believed. If very large, there wasn’t time for them to coalesce following the Big Bang. This model suggests instead that they can be much smaller black holes, thus allowing time for their formation without contradicting present Big Bang cosmology.

There is of course a lot of uncertainty here. For example, GLIMPSE-17775’s data is microlensed, which distorts it. While scientists think they understand the distortions fully, their inability to see this object and the foreground object doing the microlensing from multiple perspectives requires them to make many assumptions that cannot be proven, and could very well be wrong.

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Science operations about to resume on Europe’s two-satellite Proba-3 space telescope

8:39 am

The Proba-3 mission
The Proba-3 mission. Click for original.

After months of trouble-shooting after losing contact with the coronagraph probe of Europe’s two-satellite Proba-3 solar space telesscope in February 2026, engineers have successfully resumed precise formation flying of the two spacecraft, and are about to resume full science observations of the Sun’s corona.

The mission is explained in the graph to the right. In February all contact with the coronagraph, which holds the mission’s science instruments, was lost. After a month of struggle, engineers regained contact, but it required another few months of trouble-shooting to pin down the cause of the problem and fix it. The press release provides almost no information about that cause, other than this one quote that hints it was software-based.

“One by one, we have checked the status of each of the spacecraft’s subsystems. We have also been able to successfully perform the operations that proved critical in February,” says Damien. “Back then, it triggered the unfortunate chain reaction that led to loss of connection with the spacecraft, but after patching the root cause in the software, we were confident that this activity will cause no further issues.”

With both spacecraft once again operating in tandem, the occulter can block the Sun’s light so the coronagraph can observe the Sun’s corona, its atmosphere. Essentially, Proba-3 creates an on-going artificial eclipse so as to make the corona visible for study.

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The rings of Saturn

1:29 pm

Saturn's rings in 2006
Click for original image.

Cool image time! Rather than post another Mars image, I decided today to dig back into the Cassini orbiter archives, which orbited Saturn for almost fourteen years, beginning in 2004.

The picture to the right, reduced and sharpened to post here, was taken on September 6, 2006 from about 397,000 miles away. It has a resolution of about 22 miles per pixel, so no object smaller than that is resolved.

This wide and sweeping view of the sunlit rings of Saturn takes in the impressive variety in their structure — from the clumpy and perennially intriguing F ring to the many waves, ringlets and gaps in the A and B rings and the Cassini Division in between.

The F ring is the outermost thin clumpy ring. The B ring is the brighter set of rings inside the wide Cassini Division, with the A ring the darker set beyond. For a labeled map of all the rings and gaps go here. The seemingly incoherent naming sequence is because the rings are named alphabetically in their order of discovery. Thus, the A ring was first identified, followed by the inner B Ring. The F ring was discovered by the Pioneer 11 when it flew past Saturn in 1979.

While the many Cassini wide-view images of Saturn’s rings tend to look somewhat the same, they all remain breath-taking regardless. Imagine a hotel in orbit around Saturn, where you could look out your window and see this evolve over time as your spacecraft orbited the ringed planet.

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Astronomers find another quasar in the early universe that really shouldn’t be there

9:28 am

The uncertainty of science: Using archival data from the WISE space telescope, astronomers have now identified another unexpected quasar in the early universe, only 850 million years after the Big Bang, that also flickers in several wavelengths.

The quasar’s flicker enabled the researchers to determine that, surprisingly, the ancient quasar’s whirlpool of gas and dust, known as an accretion disk, resembled a flat pancake, similar in shape to that of more modern-day quasars.

Their findings add to a longstanding mystery in cosmology: Why do supermassive black holes exist so early in the universe’s history? Physicists have assumed that a flat accretion disk reflects a relatively mature black hole that is in a calm and stable state. Black holes that are just starting to form, like those in the very early universe, should be more unsettled systems, with accretion disks that appear more puffy and chaotic.

The flat accretion disk around this very early quasar heightens the mystery of how supermassive black holes can grow and mature in a very short amount of cosmic time.

They estimate the quasar energy output is equivalent to about 12 trillion suns. Its flickering, ranging about 20% in power, makes it the first such flickering quasar found this early in time. Such early quasars however are not unique. Astronomers have found about 200, all of which should not exist, based upon present Big Bang cosmology. There simply hasn’t been enough time for them to evolve, based on present theories of galactic formation.

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Curiosity’s looks up Valle Grande to its future travels

10:19 am

Panorama, June 8, 2026
Click for high resolution. For original images go here, here, and here.

Overview map
Click for interactive map.

Cool image time! The panorama above was created by me using three pictures taken today by the left navigation camera on the Mars rover Curiosity (see here, here, and here).

The overview map to the right provides the context. The white dotted line indicates Curiosity’s actual travels, while the red dotted lines its planned route, both in the past and in the future. The blue dot marks its approximate position when these images were taken. The yellow lines indicate approximately the view.

The panorama looks up this spectacular valley, which the science team has named Valle Grande. The red dotted line on the panorama is my guess as to the rover’s future route. It will likely not follow such a straight path, but weave back and forth as the science team directs it to look at interesting geological features along the way.

What remains unknown is the route the rover will take once it reaches those light-colored hills in the distance. The science team so far not indicated any chosen route through those hills. I suspect they want to get closer and do some on-site scouting before making any decision. The nature of that light terrain remains unknown. It could be easily traversed, or it could be a problem. From a distance it looks very soft, and thus it will likely required close inspection to make any definite plans.

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Astronomers measure weight of supermassive black hole 10 billion light years away

9:13 am

In a new record for the farthest measurement yet achieved (10 billion light years away), astronomers have now used the Webb Space Telescope obtain a reasonably accurate measurement of the mass of supermassive black hole in the early universe, estimated to be six billion times the mass of our Sun.

The stars orbiting Sag A*
The stars orbiting Sag A* at the center of our own
galaxy, the Milky Way. Click for original image.

The black hole’s mass is about 6 billion times that of the sun, and is being observed at a time when the universe was only about 3 billion years old, about a quarter of its current age, offering unprecedented details into black holes in the early universe.

To find this, the team used data from NASA’s James Webb Space Telescope to track the motion of stars orbiting around the otherwise invisible black hole to measure its mass. Though the technique – known as stellar dynamics – has been used to measure dormant black holes in galaxies much closer to Earth, this is the first time it has been used to weigh one located such a great (cosmological) distance away.

For comparison, the Milky Way’s central super-massive black hole, Sagittarius A* (pronounced “A-star”), has been estimated at four million solar masses, using this same technique. The graphic to the right shows the various stars orbiting Sagittarius A* that have been tracked now for several decades in the infrared. As their orbits are refined, astronomers can use those orbits to determine the mass of the central object.

The scientists have now been able to do the same with this galaxy ten billion light years away. These observations however are certainly preliminary, and will be refined in the coming decades as more data is obtained.

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Martian glacier flowing around a recent small crater impact

12:37 pm

A Martian glacier flowing arond a recent crater impact
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken on May 3, 2026 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this a “crater on debris covered glacier.” The crater, the dark spot in the upper center, is only about 450 feet across. The impact apparently took place onto this glacial slope, and since then the glacier has continued to flow downhill (as indicated by the arrows), flowing around the denser material pounded down by the impact.

The elevation loss within this image is about 300 feet, along a distance of just under two miles. How long it took this glacial material to flow this much however is unknown. Nor is it known when this happened. The orbital data so far of all Martian glaciers suggests they are at this time inactive, neither growing or shrinking.
» Read more

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Gigantic slumping Martian cliffs

11:14 am

Gigantic slumping Martian cliffs
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken on May 5, 2026 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this an “alluvial fan.” What we are looking at is the top 5,700 feet of a 9,400-foot-high cliff which is slumping downward. As it does so, its outer layers have been falling downward into the canyon below almost like liquid, producing the slope’s streaked look.

According to this definition, alluvial fans…

are mounds of coarse grained sediments formed when a confined stream disgorges into an unconfined area. They typically occur along the margins of mountain ranges where bedrock incised channels draining uplands spill out on to broad open valley floors. Alluvial fans occur in areas with significant topographic relief caused by rapid subsidence or uplift (rift basins, foreland basins, fold-and-thrust belts, etc.).

While the definition implies these fans only form from the flow of liquid water, that does not have to be the case. Many fans form from the long term downward motion of material from mountainsides into lower valleys or canyons, though water — either by rain, a freeze-thaw cycle, or streamflow — is usually a factor in causing this erosion.

At this location something has made that cliff slump, and in doing so produced the flow patterns on that slope
» Read more

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Venturi Space expands investment in new French factory for building Astrolab’s rover

8:59 am

Venturi Space, the European half of the partnership with the rover startup Astrolab, is increasing its investment in a new French factory from 100 million to 250 million euros.

On 1 June, Venturi Space announced that it had increased its expected investment in the new facility to €250 million. The announcement indicated that it would no longer begin with the initial smaller facility and would instead move directly to the full 16,000-square-metre planned “technology centre.” This likely accounts for the additional €150 million in funding.

According to the company’s 1 June press release, the facility will be used for the “design and manufacture of critical technologies for lunar and Martian mobility, as well as [for] the assembly of the rovers developed by the company.” …Venturi Space is providing wheels, batteries, and battery management systems to US-based Venturi Astrolab for use aboard its rovers. During a 26 May event, NASA announced that Venturi Astrolab was one of two companies selected to build rovers for the agency’s Artemis programme.

The partnership is an unusual one. Venturi Space and Astrolab are separate companies, working together to build Astrolab’s rovers for NASA. Venturi however is also developing its own rover for the European Space Agency.

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NASA officially ends its MAVEN Mars orbiter mission

8:42 am

High altitude wind patterns on Mars
Mars’ global high altitude wind patterns,
found by MAVEN.

More than six months after engineers lost contact with the Mars orbiter MAVEN, NASA today officially ended the mission, determining the spacecraft is “not recoverable.”

The agency convened an anomaly review board in February to evaluate recovery efforts and assess the spacecraft’s probable current state. The review board has determined that the MAVEN spacecraft is not recoverable, and it is no longer capable of performing its science and data relay mission, which is consistent with the mission team’s findings.

Telemetry from MAVEN prior to the spacecraft’s passage behind Mars in December showed all subsystems working normally. After the spacecraft emerged, NASA’s Deep Space Network (DSN) did not observe a signal. A brief fragment of telemetry data from analysis of radio signals recorded by the DSN’s open-loop receivers indicated the spacecraft was in safe mode and rotating at an unusually high rate when it emerged from behind Mars, indicating a disruption in MAVEN’s orbit trajectory. The review board concluded that due to this rotation, the batteries on the spacecraft had drained, causing the communications system to lose power and rendering MAVEN in an unrecoverable state.

The actual cause of the rotation remains uncertain.

MAVEN’s mission was to study the atmosphere and surrounding environment of Mar. It gave scientists their first data on how Mars could have lost both its atmosphere as well as a significant amount of its initial supply of water. It also produced the first map of the red planet’s high altitude winds, finding that even at high altitude the winds shift around the Tharsis Bulge where Mars’s biggest volcanoes are located.

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Orbital tug startup Impulse Space raises $500 million in private investment capital

11:01 am

Impulse's tug and proposed lunar lander
Impulse’s Helios tug, transporting its proposed
lunar lander to the Moon. Click for original image.

The orbital tug startup Impulse Space announced today that it has successfully raised $500 million in private investment capital.

The round was co-led by 137 Ventures and BANNER VC, bringing the company’s total capital raised to over $1 billion. The funding will support hiring and manufacturing growth as the company scales its effort to build in-space mobility infrastructure: the vehicles, propulsion systems, and operational architecture that determine where and how spacecraft move after launch.

The company was founded by Tom Mueller, who was one of SpaceX’s first employees and helped develop the Merlin engine used on the Falcon 9. It has a fleet of tugs, with its Mira tug having already completed a number of missions. Its larger Helios tug is scheduled for its first mission next year.

Hat tip reader Nate P.

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The wind speeds on seven exoplanets also suggest presence of magnetic fields

10:54 am

Astronomers using two different ground-based telescopes were able to measure the wind speeds on seven different gas giant exoplanets, and found the speeds also suggested the presence of planetary magnetic fields, the first time such magnetic fields have been deduced on an exoplanet.

In the study, the researchers investigated the wind speeds on seven exoplanets orbiting different stars. These are gas giants similar to Jupiter, which are very close to their star. Elspeth Lee explains: “The rotation of the planets was synchronized with their orbits by the tidal forces of the parent star. Just as we only ever see one side of the moon, these planets always have one side facing the star. Thus, a glowing hot day side and a permanently dark night side have formed on the planets. The extreme temperature differences in turn lead to the generation of extremely strong winds.”

…The research team was able to show that wind speeds of around 7,200 km/h to over 25,000 km/h prevail on the exoplanets. For comparison: the fastest winds measured on Jupiter reach speeds of around 1,500 km/h.

The data showed that the hotter the planet, the slower the wind, the opposite of what was expected. The scientists believe that each planet’s magnetic field is acting to brake the winds, with the hotter planets likely having more powerful fields.

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Webb detects methane being released by interstellar comet 3I/Atlas

9:21 am

Comet 3I/Atlas's methane as seen by Webb
Comet 3I/Atlas’s methane as seen by Webb.
Click for full image.

Using the Webb Space Telescope, astronomers have now detected methane in the cloud of material released by the interstellar comet 3I/Atlas as it zipped past the Sun last fall.

The observations were taken using Webb’s MIRI (Mid-Infrared Instrument) on two separate dates as the comet traveled back out of our solar system after whipping around the Sun (post-perihelion). The first observation occurred Dec. 15 to 16, when the comet was about 205 million miles from the Sun. This was followed by a second observation Dec. 27, when the comet was about 236 million miles from the Sun.

For the first time on an interstellar visitor, Webb directly detected methane gas. Methane is highly volatile, meaning it sublimates from solid ice into a gas very easily. Its delayed appearance in comet 3I/ATLAS suggests it was buried below the comet’s top surface layer and protected from sublimation until heat from the comet’s close pass to the Sun reached deeper parts of the icy subsurface. The amount of methane relative to water found is surprisingly high, with few similar analogs in our own solar system.

Webb’s observations also confirmed that comet 3I/ATLAS remains unusually rich in carbon dioxide, releasing far more carbon dioxide relative to water when compared to typical solar system comets.

You can read their peer-reviewed paper here [pdf]. This new data confirms that Comet 3I/Atlas is not from our solar system, as its make-up is sufficiently different from solar system comets to show this. It also gives us a hint as to the solar system it came from. At the same time, the comet’s behavior is remarkably similar to solar system comets, suggesting our solar system evolved much like others.

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An active galaxy peered at by Webb in the infrared

10:57 am

M77 as seen by Webb
Click for original image.

Cool image time! The false-color infrared image to the right, cropped and reduced to post here, was taken by the Webb Space Telescope as part of a research of “massive, nearby, star-forming galaxies.” It shows Messier 77 (M77), a barred spiral galaxy located 45 million light-years away.

What makes the image cool are the eight diffraction spikes, which are an artifact of Webb and its camera.

Called diffraction spikes, they are created because the intense light from the unresolved AGN is bent (“diffracted”) very slightly at the edges of Webb’s hexagonal mirror panels and around one of the struts that hold up its secondary mirror. This distinctive six-plus-two-pointed pattern is the same for any image taken by Webb. For diffraction spikes to appear, the light source has to be very bright and very concentrated, so they’re most often seen on stars. But in some galaxies, as here, the nucleus is bright and compact enough to make diffraction spikes appear as well.

In the case of M77, the nucleus is especially bright.

At the heart of M77 is a compact region filled with hot gas that handily outshines the rest of the galaxy put together, even overcoming the light-gathering capacity of Webb’s cameras. This is an active galactic nucleus (AGN), and it’s powered by M77’s central supermassive black hole, which is eight million times as massive as our Sun. Gas in the galaxy’s central regions is pulled by the strong gravity into a tight and rapid orbit around the black hole, where it crashes together and heats up, releasing tremendous amounts of radiation.

The result is this very cool image that also highlights a great deal about galaxies and their evolution.

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