BepiColumbo completes third Mercury flyby

Mercury as seen by BepiColumbo
Click for original image.

On June 19, 2023, the European Mercury orbiter BepiColumbo made the third of six planned flybys of Mercury on its way to orbit around that planet in 2025.

The closest approach was only 146 miles above the planet’s surface. Though no pictures were taken at that point because it was Mercury’s night side, as the spacecraft moved away it used one of its monitoring cameras, designed primarily to monitor the spacecraft itself, to look back at the planet. The picture to the right, cropped, reduced, and sharpened to post here, is one of the first taken. From its caption:

The image was taken at 19:49 UTC (21:49 CEST) by the Mercury Transfer Module’s monitoring camera 3, when the spacecraft was about 2536 km from the planet’s surface. Closest approach took place at 19:34 UT (21:34 CEST) on the night side of the planet at about 236 km altitude. The back of the Mercury Planetary Orbiter’s high-gain antenna and part of the spacecraft’s body is also visible in front of Mercury in this image.

Despite the dark nature of the image, several interesting geological features are seen in beautiful detail. Of particular interest is Beagle Rupes, a 600 km-long scarp that snakes over the surface. In this view it is seen cutting through a distinctive elongated crater named Sveinsdóttir, which likely got its shape from an impactor striking the surface at an angle.

The next flyby will occur on September 5, 2024.

Looking down a canyon on Mars

Looking down a canyon on Mars
Click for original image.

Cool image time! The picture to the right was taken on June 17, 2023 by Curiosity’s high resolution camera, looking back down Gediz Vallis and out across the distant floor of Gale Crater, far below. The white dotted line shows the route within this image where Curiosity had previously traveled inside this canyon, coming up around that shadowed mesa and then off to the west to try to get to terrain that it had earlier retreated because it was too rough on the rover’s wheels. Its subsequent path to the spot where this picture was taken was off to the left of the image, out of view.

This picture illustrates well the steepness and roughness of the mountainous canyon through which Curiosity presently travels. The small mountains visible on the floor of Gale Crater, about sixteen miles away, are no more than 450 feet high. The floor of the crater is 1,900 feet below where Curiosity present sits.
» Read more

A Martian crater with a wake of lava

Overview map

Cool image time! Today’s cool image begins with the overview map to the right. The white dot marks its location, on the western edge of Amazonis Planitia and about 1,000 miles east of the giant shield volcano Elysium Mons.

This is a region of numerous flood lava events that appear to cover the knobby mountainous terrain that was once here. We know that past terrain was knobby because in the black outline just south of this picture the knobs are everywhere, short peaks sticking up from a very flat flood lava plain. The region is also on the northern edge of the dry equatorial regions of Mars, at 27 degrees north latitude. It is likely there is little near surface ice here.

These details will help explain the cool image itself.
» Read more

The icy mesas of Mars’ glacier country

Overview map

The ice mesas of Mars' glacier country
Click for original image.

Cool image time! The picture to the right, rotated, cropped, and reduced to post here, was taken on March 25, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this image “Cross-Section of Glacier-Like Form,” probably because the mesa in the center of the picture clearly shows numerous layers as you descend from its peak to the surrounding plains, an elevation difference of about 200 feet.

The white dot about 250 miles due south of Lyot Crater on the overview map above marks the location of this mesa, inside the chaos terrain of Deuteronilus Mensae that is the western section of the 2,000 long strip in the northern mid-latitudes of Mars that I call glacier country, since practically every image, like today’s, suggests the presence of glaciers.

The oblique mosaic below, created using MRO’s context camera images, illustrates this fact even more spectacularly.
» Read more

Lightning on Jupiter

Lightning on Jupiter
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on December 30, 2020 by Juno during its 31st close fly-by of Jupiter, and was enhanced and processed by citizen-scientist Kevin Gill.

In this view of a vortex near Jupiter’s north pole, NASA’s Juno mission observed the glow from a bolt of lightning. On Earth, lightning bolts originate from water clouds, and happen most frequently near the equator, while on Jupiter lightning likely also occurs in clouds containing an ammonia-water solution, and can be seen most often near the poles.

Juno was about 20,000 miles above Jupiter’s clouds when it took this picture, located at about 78 degrees north latitude.

Drainage channel between two Martian hollows

Drainage channel between two Martian hollows
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on April 28, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Dubbed a “terrain sample” by the camera team, it was likely taken not as part of any specific research project but to fill a gap in the camera’s schedule so as to maintain that camera’s proper temperature. When they have to do this, they try to pick interesting targets, though there is no guarantee the result will be very interesting.

In this case the camera snapped what appears to be a drainage channel between two deeper hollows. The channel sits about 100 feet above the western hollow and 260 feet above the eastern hollow. This makes some sense, as the overall drainage in this region is going from the west to the east, and then to the north.
» Read more

Astronomers detect vaporized elements in atmosphere of hot Jupiter-sized exoplanet

Using the Gemini telescope in Hawaii, astronomers have detected several elements in atmosphere of hot Jupiter-sized exoplanet, dubbed WASP-76b, that would normally be found in rocks, but here are vaporized because the exoplanet orbits so close to its star.

In 2020 and 2021, using Gemini North’s MAROON-X (a new instrument specially designed to detect and study exoplanets), Pelletier and his team observed the planet as it passed in front of its host star on three separate occasions. These new observations uncovered a number of rock-forming elements in the atmosphere of WASP-76b, including sodium, potassium, lithium, nickel, manganese, chromium, magnesium, vanadium, barium, calcium, and, as previously detected, iron.

Due to the extreme temperatures of WASP-76b’s atmosphere, the elements detected by the researchers, which would normally form rocks here on Earth, are instead vaporized and thus present in the atmosphere in their gaseous forms. While these elements contribute to the composition of gas giants in our Solar System, those planets are too cold for the elements to vaporize into the atmosphere making them virtually undetectable.

The data not only suggests such elements exist in the solar system’s gas giants, but that such elements are common in solar systems elsewhere. That possibility increases the chances of other planets like Earth, capable of sustaining life as we know it, in addition to sustaining life as we don’t know it.

BepiColumbo about to do third Mercury flyby

In its long journey to get into orbit around Mercury, BepiColumbo needs to do nine different flybys of the inner planets, with third fly-by of Mercury coming up on June 19, 2023.

The mission launched into space on an Ariane 5 from Europe’s Spaceport in Kourou in October 2018 and is making use of nine planetary flybys: one at Earth, two at Venus, and six at Mercury, to help steer into Mercury orbit.

After this flyby, the mission will enter a very challenging part of its journey to Mercury, gradually increasing the use of solar electric propulsion through additional propulsion periods called ‘thrust arcs’ to continually brake against the enormous gravitational pull of the Sun. These thrust arcs can last from a few days up to two months, with the longer arcs interrupted periodically for navigation and manoeuvre optimisation.

The spacecraft will zip past Mercury at a height of 147 miles. If all goes well, this dual orbiter mission, carrying both a European and a Japanese orbiter will arrive in 2025, beginning a planned three year mission in different complementary orbits.

Rimstone dams in Mars’ youngest lava deposit

Rimstone dams in Mars' youngest lava deposit
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 23, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The scientists dub the features here merely as “land forms,” probably because it is difficult to explain the origins of many of these strange features. For example, why is the half-mile-wide crater filled that knobby terrain, far different than the surrounding plains? Similarly, what caused the small meandering ridges (less than five feet high) that appear to closely resemble the cave formation called rimstone dams?

And why is this terrain so generally flat and smooth?

As usual, the overview map helps explains some of this, but not all.
» Read more

Eroding glacier on Martian slope?

Eroding glacier on Martian slope?
Click for original image.

Cool image time! The picture to the right, enhanced, cropped, reduced, and sharpened to post here, was taken on April 1, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels as “Rough Ground and Bright Exposures” on the flanks of a wide mountain range on Mars, whose highest point is about 4,400 feet higher to the northeast and about 30 miles away.

The arrow indicates the downhill grade. Notice the smooth flat areas that seem to only partially cover much rougher terrain below. To my eye this top layer resembles an Earth glacier that has partly sublimated or melted away, exposing the rougher bedrock below that has been ground and scraped by the glacier previously.

However, this is not on Earth, so assuming it is like an Earth glacier is dangerous.
» Read more

Ice-filled fissure on Mars?

Ice-filled fissure on Mars?
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on February 15, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this a “Terrain Sample”, which suggests but doesn’t guarantee that it was to fill a gap in the camera’s schedule in order to maintain that camera’s proper temperature, and therefore was targeted at a relatively random but potentially interesting location.

What we see is a fissure canyon, about 250 to 300 feet deep with cliffs about 125 high, that appears surrounded and even filled with icelike features. Even the craters on the plateau above the canyon appear like they either impacted in ice, or have since been filled and eroded by that ice.

But is it ice?
» Read more

Distorted floor of a Martian crater

Overview map

Distorted floor of a Martian crater
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on February 18, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels “Mantle Layers in Southern Mid-Latitudes.”

I would be less vague. These strangely shaped features invoke the typical glacial features seen throughout the mid-latitudes of Mars. The knobs and outcrops suggest some underlying breakdown that the top layers of glacial material has covered. They also suggest some form of sublimation or erosion process to the glacier itself.

The white rectangle inside the inset on the overview map above marks this location, covering the floor of an unnamed 10-mile-wide crater in the cratered southern highlands at 41 degrees south. In this region all the craters show some evidence of this sublimation, all suggesting that there is a near-surface underlying ice layer that when exposed vanishes to leave depressions or hollows. Here however it appears that ice layer is mostly intact, the knobs and ridges indicating the shape of the bedrock and large breakdown below.

Martian dust devil where none had been before

Dust devil on Mars
Click for original image.

Today’s cool Mars image is especially cool because it is of the exact same place on Mars I had featured in a picture only a little more than one month ago. I return to this spot only a month later because the location was yesterday’s featured captioned image from the high resolution camera team of Mars Reconnaissance Orbiter (MRO). The difference is that this time the camera captured a dust devil there that wasn’t there previously. From the caption:

The dust devil is casting a shadow, which can be used to estimate its height. This image is part of ongoing monitoring activities by HiRISE of seasonal activities on Mars.

Over the years, HiRISE has observed many dust devils. Just like on Earth, dust devils develop when the Sun heats up the ground such that it warms the air directly above it. When air heats up its density decreases causing it to rise up while colder air sinks down driving local convection.

If the region is windy, the wind my end up rotating the “convection cells” caused by the vertical motion of air leading to development of a dust devil. Since the main requirements for development of such features are the presence of dust and a warm ground, we focus our monitoring of dust devils in regions on Mars that are known to be dusty (like Syria Planum), and during the late spring and summer time, when we expect the ground to be warm.

» Read more

Hubble snaps picture of another jellyfish galaxy

Another jellyfish galaxy
Click for original image.

Astronomers today released another picture of a jellyfish galaxy taken by the Hubble Space Telescope, with that picture to the right, cropped, reduced, and sharpened to post here. From the caption:

The jellyfish galaxy JO206 trails across this image from the NASA/ESA Hubble Space Telescope, showcasing a colourful star-forming disc surrounded by a pale, luminous cloud of dust. A handful of bright stars with criss-cross diffraction spikes stand out against an inky black backdrop at the bottom of the image. JO206 lies over 700 million light-years from Earth in the constellation Aquarius.

This image is the sixth and final such photograph in this survey. You can view all of these images here. The study has found that star formation does not seem to be significantly different inside the galaxy versus the tentacles that stretch out beyond due to pressure from the intergalactic material. This suggests that the influence of this intergalactic material on the formation of stars is relatively minor.

Tianzhou unmanned freighter completes month-long free flight, re-docks with Tiangong-3

Engineers today successfully re-docked a Tianzhou unmanned freighter to China’s Tiangong-3 space station after 33 days flying in formation with the station.

As is usual, China released no information about the reasoning behind this free flight, though some reasons are obvious. The station has two docking ports, and during that 33-day time period the station also completed a crew swap, with one Shenzhou capsule docking with three new astronauts while the previous crew and its Shenzhou capsule was still docked. The Tianzhou freighter had to undock to provide a port during this time period for the two manned capsules.

This formation free flight and docking was also likely testing the kind of routine maneuvers China plans to do when it launches its Hubble-class optical space telescope next year. That telescope will fly freely near the station during most of its operations. For maintenance and repair however it is my understanding that it will be brought back to the station and docked with it. The just completed independent flight of the Tianzhou freighter demonstrated this capability.

Russia to launch Luna-25 on August 11, 2023


Click for interactive map.

According to reports in Russia’s state run press, the new launch date for its Luna-25 lander to the Moon has now been scheduled for August 11, 2023.

The launch of an automatic space probe to the Moon, the Luna-25, is scheduled for August 11 this year, the tour operator RocketTrip has said on its website. “August 11 is the launch date,” the website says in the section devoted to the tour to the Vostochny spaceport for the launch of the Luna-25.

The launch had been scheduled for July. The one month delay was announced last week, with no explanation.

The map shows landing locations of three landers that are all scheduled for launch in the next four months. All are targeting spots near the Moon’s south pole (the white cross).

Barren land on Mars

Barren land on Mars
Click for original image.

It might seem strange to call any particular place on Mars “barren” when the entire planet has no visible signs of life anywhere. However, much of the surface of Mars involves wind and ice features that show evidence of change and evolution over time. The presence of apparent near-surface ice and glacial features in almost every image located above 30 degrees latitude emphasizes this sense of potential life, even if that life will only be transported from Earth and established there someday by humans.

Today’s cool image to the right, cropped and reduced to post here, has none of these features. It is dry barren bedrock, with only a faint scattering of Martian dust indicated by many faint dust devil tracks.

The picture was taken on March 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The largest and most distinct flat-topped mesa in the image is only about 100 feet high, with the north-south ridgeline to the south about 20 feet high.
» Read more

Astronomers think they have completed the census of Near Earth asteroids

Astronomers in a new paper [pdf] have concluded that the census of Near Earth asteroids is largely now complete, and have begun focusing their effort on narrowing down the list of potentially dangerous asteroids in that census. From the press release:

Researchers from CU Boulder and NASA have completed a census of hundreds of large asteroids orbiting near Earth—gauging which ones could come precariously close to our planet over the next thousand years. The researchers identified at least 20 asteroids that scientists may want to study more to make certain they pose no threat to life on Earth in the next millennium.

To be clear, the researchers say the odds of any of these rocky bodies striking the planet are extremely low, and are next to zero for the coming century. But because the fallout from such an impact would be catastrophic, it’s important to be sure, said Oscar Fuentes-Muñoz, lead author of the study. “We don’t want to alarm people, because the results are not alarming,” said Fuentes-Muñoz, a doctoral student in the Ann and H.J. Smead Department of Aerospace Engineering Sciences. “But there are a lot of uncertainties in predicting so far into the future.”

To sum up, none of those 20 asteroids has any chance of hitting the Earth in the next few hundred years. Beyond that the uncertainties make it difficult to predict. Reducing those uncertainities is now the focus of their work.

Avalanche to the east of Gale Crater on Mars

Landslide on Mars
Click for original picture.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on February 19, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows an avalanche that slumped downward out of the material that forms the interior western wall of an unnamed 25-mile-wide crater about 100 miles east of Gale Crater, where Curiosity has been roving for more than a decade.

The scientists call these types of Martian avalanches “mass-wasting events”, since the entire mass of the cliff moves downhill in a chunk, rather than as a pile of rocks that grows in size and strength as it picks up material on its way down.

It is not clear how old this slide is. A lot of the material on this slope appears to be Martian dust, some of which has flowed into the avalanche material after it had slide downhill.
» Read more

Shadowcam on South Korea’s Danuri lunar orbiter sees no obvious ice in the permanently shadowed interior of Spudis crater

Overview map

Using Shadowcam, a camera built by Arizona State University that is on South Korea’s Danuri lunar orbiter and is designed to see into very dark regions of little light, scientists have obtained optical images showing the permanently shadowed interior of Spudis Crater, located only about ten miles from the Moon’s south pole.

That picture is below. To the left is an annotated overview created from Lunar Reconnaissance Orbiter (LRO) high resolution images. The white box inside Spudis Crater indicates the area covered by the section of the Shadowcam image I have focused on. The red outlines indicate areas that are thought to be permanently shadowed. The relatively flat ridgeline between Shackleton and Spudis is one of the prime future landing sites for NASA’s Artemis program.
» Read more

Martian rootless cones

Rootless cones
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on March 8, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The camera team labeled this picture simply “Rootless Cones,” which is a feature that is created when the lava that covers the surface is thin, allowing the heated material below (which is not lava) to burst upward, producing the cone and caldera. If you look at the full image you will see other similar clusters of cones scattered about on this very flat and featureless plain. Apparently, the material that this lava plain covered had several similar bursts in a number of areas.

Such cones in this particular lava field are not rare, and in fact are evidence that this particular field is young.
» Read more

ESA to live-stream image downloads from Mars Express

To celebrate Mars Express’s 20th year in orbit around Mars, the European Space Agency (ESA) has announced that tomorrow it will for one hour live-stream the image downloads coming from the orbiter.

I have embedded that live stream below. According to the press release, new images will arrive about once every 50 seconds. The camera that will be taking the pictures however is not one of Mars Express’s main instruments, but designed instead to simply monitor the separation of the Beagle-2 lander from the orbiter in 2003. Since 2007 however the science team has used its low resolution global images of Mars for public relations, education, and even some science research.

That the science team is not providing the live feed from its high resolution camera however illustrates why Mars Express gets so little press coverage, compared to Mars Reconnaissance Orbiter (MRO). All MRO images are released to the public, usually only a month or so after they reach Earth. The ESA however has never made the archive of Mars Express accessible, as far as I have been able to discover. All it does is periodically issue a press release about once every few months touting one new image, even though the spacecraft is taking dozens daily.
» Read more

A typical glacier, on Mars

Overview map

A typical glacier, on Mars
Click for original image.

The cool image from Mars to the right, rotated, cropped, reduced, and sharpened to post here, provides us a good illustration of the lineated grooves that are typically seen on the surface of valley-confined glaciers, both on Earth and on Mars, and are also seen on the patched, grooved surface of Ganymede.

The picture was taken on March 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows what appears to be a glacier flowing through a constriction. The arrow indicates the direction of the downhill grade.

The location, indicated by the white dot inside the inset on the overview map above, marks the location, in the western end of the 2,000 long northern mid-latitude strip on Mars I dub glacier country. In these three mensae regions (Deuteronilus, Protonilus, and Nilosyrtis) of chaos terrain practically every high resolution image shows features that resemble glaciers.

In this case, the glacial flow appears to be draining from a 10-mile-wide ponded circular valley though a narrow gap.

The grooved surface of Ganymede

The grooves of Ganymede
Click for original image.

Cool image time! The picture to the right, reduced to post here, was taken on June 7, 2021 when the Jupiter orbiter Juno did a close flyby of the moon Ganymede, taking four pictures.

Citizen scientists Gerald Eichstädt and Thomas Thomopoulos have now reprocessed parts of those images to bring out the details more clearly (the other new versions available here, and here).

I have chosen to highlight the picture to the right however because it so clearly shows the puzzling grooves that cover much of Ganymede’s surface. While these parallel grooves in many ways mimic the grooves often seen on top of valley glaciers on Earth and Mars, on Ganymede they do not follow any valley floor. Instead, they form patches of parallel grooves that travel in completely different directions, depending on the patch. At the moment their origin is not understood.

These grooves are one of the mysteries that Europe’s Juice probe will attempt to solve when it arrives in orbit around Jupiter in 2031.

Webb detects large water plume released from Saturn’s moon Enceladus

Water vapor plume seen by Webb
Click for original image.

Using the infrared cameras on the Webb Space Telescope, astronomers have detected a surprisingly long and large plume of water vapor erupting from the tiger stripe fractures on Saturn’s moon Enceladus that scientists for years have detected vapor plumes.

The false color image to the right shows that plume.

A water vapor plume from Saturn’s moon Enceladus spanning more than 6,000 miles – nearly the distance from Los Angeles, California to Buenos Aires, Argentina – has been detected by researchers using NASA’s James Webb Space Telescope. Not only is this the first time such a water emission has been seen over such an expansive distance, but Webb is also giving scientists a direct look, for the first time, at how this emission feeds the water supply for the entire system of Saturn and its rings.

…The length of the plume was not the only characteristic that intrigued researchers. The rate at which the water vapor is gushing out, about 79 gallons per second, is also particularly impressive. At this rate, you could fill an Olympic-sized swimming pool in just a couple of hours. In comparison, doing so with a garden hose on Earth would take more than 2 weeks.

Though that rate of release sounds large, we must remember it is being released from a moon 313 miles across. From that perspective the rate of flow is quite reasonable.

Cracking pedestal crater near Mars’ north pole

Cracking pedestal crater near Mars' north pole
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on March 18, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). I have also rotated it so that north is to the top.

Labeled a “terrain sample” by the camera team, this picture was likely taken not as part of any specific research project, but to fill a gap in the camera’s schedule so as to maintain its proper temperature. As usual, when the camera team needs to do this, they try to pick a target of interest. Sometimes they succeed, sometimes not.

In this case, the picture is of a location only about 800 miles from the Martian north pole, on the northern lowland plains. While the section shown to the right focuses on the largest crater, the full picture includes a few others, all of which appear to have their interior floors cracking in the same way, and all appear to be pedestal craters, sitting above the surrounding terrain, though by not as much.
» Read more

China unveils next Shenzhou launch date and crew to its space station

China today revealed the next three-man crew to occupy its Tiangong-3 space station, with a planned launch in a Shenzhou crew capsule targeting May 30, 2023, Chinese time.

Because of time differences, that launch will occur tonight at 6:28 pm tonight, Pacific time. The rocket will be a Long March 2F taking off from China’s western interior Jiuquan spaceport. The rocket’s lower stages will therefore crash somewhere in China.

The crew will remain on board the station for five months, and with one astronaut the first Chinese to fly in space four times.

A fractured spot in Mars’ northern lowland plains

A fractured spot in Mars' northern lowland plains
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on February 16, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a pockmarked flat plain with a scattering of meandering hollows, each filled with ripple sand dunes that make these depressions resemble at first glance the tracks of tires.

Obviously, we are not looking at evidence of a past giant vehicle moving across the ground on Mars. The MRO science team labels these “fractures,” suggesting some past geological process caused the surface to crack in this manner, with those cracks widening with time due to erosion or sublimation.

The location of course tells us something about that process.
» Read more

The eroding north wall of glacial-filled Harmakhis Valles

The north wall of Harmakhis Valles
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on February 8, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

We are looking at the 2,400-foot-high cliff, its lower walls clearly cracking horizontally as they sag downward, with other large sections higher up appearing to have been eroded away in larger pieces.

Yet, the ground below this cliff wall appears to have no debris piles, the kind you would expect below a landslide. Instead, that ground appears to be very glacial in nature, with many linear parallel lines suggesting layers.

The overview map below provides us the context, and an explanation as to where that debris has gone.
» Read more

Knobs on the floor of a Martian caldera

Knobs on the floor of a Martian caldera
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on February 14, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and shows what the scientists have dubbed as “enigmatic knobs” located on the caldera floor of a Martian shield volcano.

The knobs themselves, while puzzling, aren’t that interesting on their own. They are no more than 100 to 200 feet high, and are relatively featureless. Since most lack a pit at their peaks, they are probably not some form of small volcanic vent, though this conclusion is uncertain. The location, at about 30 degrees south latitude, suggests the faint possibility of near surface ice, which could make these mud volcanoes, or a very specific Arctic-type permafrost mound dubbed pingos, but once again the lack of any central pit at their peaks makes these origins also doubtful.

What the knobs however revealed to me was a giant Martian shield volcano I had never noticed before, even though it was hiding in plain sight.
» Read more

1 17 18 19 20 21 27