A new theory for making liquid water once possible on Mars

In order to explain the many gullies on Mars, scientists at Brown University have now proposed a new model that says liquid water could exist periodically on the surface of Mars, caused by the cyclical changes in the planet’s rotational tilt, ranging from 11 to 60 degrees.

From editor’s summary of the paper:

Some steep slopes on Mars have gullies with morphologies suggesting that they were formed by a fluid. However, the planet’s current climate is not conducive to the melting of water ice at those locations, and mechanisms involving carbon dioxide ice do not explain the distribution of the gullies. [This paper] simulated how the climate of Mars differed when its axis tilted by different amounts over the past few million years. At a tilt of 35 degrees, the ice caps partially melted, raising the atmospheric pressure, and there were higher summer temperatures. Under these conditions, the atmospheric pressure at the gullies would be above the triple point of water, so it could melt to form a liquid.

The paper estimates these conditions last existed on Mars about 630,000 years ago, though the process repeated itself many times over the past several million years, each time causing some water ice to melt and flow down to form gullies. As the planet’s inclination then changed, conditions changed as well, producing colder temperatures at these latitudes so the water froze once again.

Though this is only a model with many uncertainties, it suggests a more reasonable explanation for the past existence of liquid surface water on Mars, temporary, periodic, and rare, than most other models. Combined with the possibility that ice glaciers themselves could have contributed to the formation of many of Mars’ riverlike channels, it seems that scientists are beginning to form a rough concept explaining how Mars evolved to what it is today.

The icy floor of one of Mars’ most ancient craters

Overview map

The icy floor of one of Mars' most ancient craters
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 3, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It focuses on a small crater in the center of 265-mile-wide Greeley Crater, named in 2015 after the late Ron Greeley, who had been involved in almost every planetary mission from the 1960s until his passing in 2011.

Greeley Crater is intriguing because of its age, estimated to be about four billion years old, as indicated by crater counts and the crater’s heavily eroded condition.

This ancient crater, which has already been heavily eroded and filled with sediment, is difficult to make out against the Martian landscape due to its relatively shallow depth of only 1.5 kilometres – indeed, the crater rim has disappeared altogether in places.

Greeley is also intriguing by its location in the southern mid-latitudes. On the overview map above the red dot inside Greeley marks the location of today’s picture. This is a region with lots of evidence of ice and glacial features inside craters. The picture shows a small two-mile-wide crater about 500 feet deep inside Greeley. Both inside and outside the crater the surface suggests ice, either in glacial formations on the crater floor or as a soft flat plain that allows impacts to sink in without producing a rim or much ejecta.

While research has suggested a large number of glaciers in the outlined region on the western edge of the overview map, the evidence continues to build that near-surface ice exists everywhere throughout the mid-latitudes of Mars.

Perseverance spots a doughnut-shaped rock

Doughnut-shaped rock in Jezero Crater
Click for original image.

The Mars rover has spent the last few months exploring just beyond the western rim of half-mile-wide Belva crater, which sits on top of the delta that eons ago flowed into 30-mile-wide Jezero Crater. During that time the science team has been using its various cameras to study the surrounding terrain.

One of those cameras is the SuperCam Remote Micro Imager. This camera is a variation of Curiosity’s ChemCam, designed initially to look very closely at nearby objects. The Curiosity team however discovered they could also use ChemCam to look at distant objects, and in this case the Perseverance team was doing the same with SuperCam, gazing outward at more remote features.

The result was the picture to the right, cropped, reduced, brightened, and sharpened to post here. It was taken on June 23, 2023, and shows what appears to be a several-foot-wide rock with a hole in its center. According to the SETI Institute’s tweet that publicized the picture, the rock might be “a large meteorite alongside smaller pieces.”

If this was Curiosity I would be certain the science team would take the rover close to the rock. The Perseverance team however seems to have different goals, mostly centered on finding drill spots for obtaining its core samples for later return to Earth. It has not therefore been as exploratory as Curiosity. It seems to have rarely diverged from its planned route, and when it has it has not done so to look at singular features like this. We shall see what they finally decide.

Another tourist site for future Starship passengers on Mars

Another tourist site for future Starship passengers on Mars
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 11, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the northwest quadrant of a 7-mile-wide crater whose western rim was smashed by the later impact that created a smaller 2.8-mile-wide crater.

What makes this location interesting is what fills both craters, and how that material appears to flow through a gap in the smaller crater. The color strip suggests the peaks of the rim and small knobs are dust-covered, while the flat materials below are either “coarser-grained materials” that might also have elements of frost or ice within them. The science team thinks ice is involved, having labeled this picture “Ice Flow Features between Craters.”
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Spring near the Martian north pole

Spring near the Martian north pole
Click for original image.

Overview map

Cool image time! The picture above, rotated, reduced, and brightened slightly to post here, was taken on April 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It cuts a swath across an eleven-mile-wide crater only about 500 miles from the edge of Mars’ north pole ice cap.

The overview map to the right marks its location, as indicated by the white dot on the right edge of the map. The inset shows the soft and likely icy nature of the surface in which this impact occurred. The crater resulted in a secondary outside ripple, that quickly hardened after impact.

The image was taken during spring, shortly after the sun’s light hit this crater. The cracks in the ice indicate long term sublimation that is slowly reducing the amount of water ice inside the crater. Like mud cracks in the desert after a puddle has evaporated, the ice here is cracking to produce polygon fractures.

It is also very likely that everything here is coated with a thin mantle of clear dry ice, deposited as snow from the atmosphere in the winter and then sublimating away with the coming of spring. That spring dry ice sublimation is likely ongoing, and this picture is probably an attempt by scientists to detect that process.

Why the surface colors shift from aquablue to orange might have to do with that sublimation process, or it might be revealing areas covered with dust (orange). That the northern parts of the strip is blue and the southern parts orange suggests the former. Or not. I don’t have enough information to answer this question with any confidence.

Zhurong data shows very weak magnetic field at landing site

Using data accumulated by Zhurong while it was still rovering on Mars, Chinese scientists have determined that the weak Martian magnetic field at Utopia Basin where the rover landed was very weak, much weaker than expected.

Results from NASA’s Mars’ lander InSight, which landed about 2,000 km southeast of Zhurong, have revealed that the crustal magnetic field at InSight’s landing site was an order stronger than that inferred from orbital measurement. Measurements from Zhurong, however, revealed the opposite result, with the average intensity an order less than that inferred from orbit.

The weak field suggests that the crust under Utopia Basin was never magnetized, or was demagnetized by some large later impact.

Meanwhile, no word on Zhurong itself, which either remains in hibernation or has died due to lack of power caused by the dusty Martian winter.

China conducts parachute tests for returning asteroid sample to Earth

China has successfully conducted tests of the parachute design that will be used by the sample return capsule of its Tianwen-2 mission to grab samples from the near Earth asteroid dubbed 469219 Kamoʻoalewa.

The mission will launch on a Long March 3B rocket in 2025, and rendezvous with the asteroid in 2025. After getting its samples and releasing the sample return capsule, the plan is to then send Tianwen-2 to Comet 311P/PANSTARRS, arriving in the 2030s.

The probe uses fanlike solar panels, apparently copied from those used by NASA’s Lucy asteroid probe. China also has copied the touch-and-go sample grab methods used by OSIRIS-REx and Hayabusa-2, but it will also try its own original idea, to anchor to the asteroid and use drills in the probe’s landing legs.

A northern lowland ice sheet on Mars?

A northern lowland ice sheet on Mars?
Click for original image.

Cool image time. The picture to the right, cropped to post here, was taken on March 14, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Dubbed simply a “terrain sample,” this image was likely taken not as part of any specific research project, but to fill a gap in the camera’s schedule in order to maintain its temperature by taking regular images. When the camera team needs to do this, they try to find interesting locations not previously photographed. Sometimes the photos turn out somewhat boring. Most of the time however they capture something very intriguing.

In this case, the intriguing feature of this picture is its stippled surface that seems to overlay a relatively flat surface underneath, with some faint covered craters visible. On top are several more recent craters that suggest either the impact landed in very soft material, thus producing little ejecta and no crater rims or the craters are not craters but sinks, places where the ground is subsiding due to some underground process.
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Webb makes first detection of one particular carbon molecule

The uncertainty of science: Using the Webb Space Telescope, astronomers have made the first detection of methyl cation (pronounced cat-eye-on) (CH3+) in space, located in a baby solar system the star-forming region of the Orion nebula about 1,350 light years away.

While the star in d203-506 is a small red dwarf, the system is bombarded by strong ultraviolet (UV) light from nearby hot, young, massive stars. Scientists believe that most planet-forming disks go through a period of such intense UV radiation, since stars tend to form in groups that often include massive, UV-producing stars.

Typically, UV radiation is expected to destroy complex organic molecules, in which case the discovery of CH3+ might seem to be a surprise. However, the team predicts that UV radiation might actually provide the necessary source of energy for CH3+ to form in the first place. Once formed, it then promotes additional chemical reactions to build more complex carbon molecules.

Broadly, the team notes that the molecules they see in d203-506 are quite different from typical protoplanetary disks. In particular, they could not detect any signs of water. [emphasis mine]

In the next day or so we shall likely see a number of stories in the mainstream press shouting some variation of “Webb finds key element of life!” Webb has done no such thing. It has found a carbon molecule not seen previously, which simply provides scientists another small data point in trying to understand the development of complex solar systems.

The highlighted sentences make clear the uncertainty in this field and the general shallow amount of knowledge. For example, why carbon molecules but no water, which is made up of hydrogen and oxygen, both ubiquitous throughout the universe and found in large amounts in star-forming regions?

Determining whether a Martian crater is impact or volcanic

Determining whether a Martian crater is impact or volcanic
Click for original image.

Overview map

Cool image time! The picture above, rotated, cropped, reduced, and sharpened to post here, was taken on March 22, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The camera team labeled this “Crater rim and ejecta,” which subtly reveals the picture’s scientific purpose.

The white dot on the overview map to the right indicates the location of this 15-mile-wide unnamed crater, about 150 miles northwest of where the rover Opportunity landed and traveled south to the rim of Endeavour Crater. It also shows in the inset that the crater appears to sit in the center of an upraised mound, suggesting it was formed not by impact but by volcanic processes.

This picture however says otherwise. The many small mounds and mesas to the south of the crater rim are not what one would expect on the apron of a volcano. Instead, they suggest this crater is an impact, with those mounds the eroded ejecta from that impact, now also partly buried by dust. This hypothesis is strengthened by the data from Opportunity, which found a great deal of impact ejecta during its travels, possibly from the very event that created this crater.

A spectacular Martian glacier

Overview map

A spectacular Martian glacier
Click for original image.

Mars appears to be a planet filled with past surface flows, none of which are active today but all of which came from widely different geological processes. Yesterday’s Martian cool image showed the hardened remains of a lava flow on Mars. Today’s cool image shows us what might one of the best examples of the kind of glacial evidence orbital images have been finding throughout the mid-latitudes of Mars.

The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 27, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The red dot in the inset on the overview map above indicates its location on Mars, in the chaos region dubbed Protonilus Mensae that forms the central part of the 2,000-mile-long Martian region in the north mid-latitudes I dub glacier country. In this region almost every high resolution image shows evidence of glaciers, all protected by a thin layer of dust and debris so they do not sublimate away.

This particular glacier fills a canyon carved into the southern cliff of a mile-high mesa five miles by ten miles in size, and drops dramatically almost 4,700 feet in about four miles. In fact, it so epitomizes what glaciers look like that the camera team for MRO’s high resolution camera used a 2020 image to give a quick lesson on how to spot a glacier on Mars.

This 2023 picture was likely taken as part of a long term monitoring program. Though planetary scientists presently do not think the glaciers on Mars are active and moving, this assumption is not yet confirmed. Taking repeated pictures of this same glacier over time will eventually answer this question.

More direct images released of exoplanet 87.5 light years away

Keck images of exoplanet over time

The Keck Observatory in Hawaii has now released its own image of the exoplanet AF Leporis b, following up the images produced by the Very Large Telescope (VLT) released in February.

The direct images Franson’s team captured revealed that AF Lep b is about three times the mass of Jupiter and orbits AF Leporis, a young Sun-like star about 87.5 light-years away. They took a series of deep images of the planet starting in December 2021; two other teams also captured images of the same planet since then.

What make the Keck observations most interesting is that they captured over time the motion of the exoplanet as it orbited its star. The two images to the right show this motion.

The paper, available here, was published today in Astrophysical Journal Letters. This particular star also has a debris disk surrounding it, suggesting it is a young solar system still in the process of forming. From the paper’s conclusion:

AF Lep joins other young planet hosts with debris disks such as β Pic, HR 8799, HD 206893, and HD 95086, reinforcing indications of a higher frequency of long-period planets orbiting stars hosting debris disks.

A lava flow on a Martian lava plain

A lava flow on a Martian lava plain
Click for original image.

While much of surface of the Martian equatorial regions is comprised of volcanic flood lava, the place where it is most obvious and evident is on the flanks of the three giant volcanoes of the Tharsis Bulge. Here, lava did not simple spout from surface vents to flood low-lying large areas, filling those depressions quickly almost like water. Instead it issued from vents on the slopes of those mountains, or from their calderas at their peaks, and flowed downhill almost like tsunamis of magma.

The picture to the right, rotated, cropped, reduced, and sharpened to post here, is a great example. Taken on March 11, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), it shows the foot of one such flow, frozen in place as it oozed down hill from the Arsia Mons, about 300 miles away to the northwest.
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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.
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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.
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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.
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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.
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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.
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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.
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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?
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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.

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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.
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