Tag: science

Scientists: Enceladus’ tiger stripes come from underground ocean

9:58 am

The uncertainty of science: Using a new computer model, scientists now think they have shown how on the Saturn moon Enceladus pressure from an underground ocean can push through cracks to produce geysers on the surface.

Rudolph and his colleagues ran a physics-based model to map the conditions that could allow the cracks from the surface to reach the ocean and cause the eruptions. The model accounts for cycles of warming and cooling that last on the scale of a hundred million years, associated with changes in Enceladus’ orbit around Saturn. During each cycle, the ice shell undergoes a period of thinning and a period of thickening. The thickening happens through freezing at the base of the ice shell, which grows downward like the ice on a lake, Rudolph said.

The pressure exerted by this downward-expanding ice on the ocean below is one possible mechanism researchers have proposed to explain Enceladus’ geysers. As the outer ice shell cools and thickens, pressure increases on the ocean underneath because ice has more volume than water. The increasing pressure also generates stress in the ice, which could become pathways for fluid to reach the surface 20-30 kilometers away.

You can read the paper here.

Be warned: This is only a model. Moreover, its conclusions suggest that this mechanism will not work on Jupiter’s moon Europa, which has many planet-wide crack-like features that suggest (as yet unconfirmed) a bubbling up from below.

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Sharpest radio image ever taken of newly discovered space object

9:11 am

The first known Odd Radio Circle (ORC)
Click for full image.

The uncertainty of science: Astronomers, using the MeerKat radio telescope in South Africa, have taken the best radio image yet of a newly discovered type of astronomical object, dubbed whimsically as an odd radio circle (ORC).

The photo to the right is that image. While it is reminiscent of the many planetary nebulae seen in visible light that astronomers have been studying since the 1800s, this weird shape is only seen in radio frequencies, and it is much much larger.

Odd radio circles are so named because they’re large, circular objects which are bright around the edges at radio wavelengths, but which can’t be seen with optical, infrared or X-ray telescopes – and at this stage, astronomers don’t really know what they are.

And they’re massive – about a million light years across, making them sixteen times larger than our own galaxy. But despite their gargantuan size, the objects are difficult to spot, hiding in plain sight.

Planetary nebulae are generally the size of solar systems.

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The journey so far of China’s Zhurong Mars rover

11:07 am

Zhurong's journey on Mars, as seen by MRO
Click for full image.

Elevation map and wider overview
Click for full image.

Cool image time! The science team for the high resolution camera on Mars Reconnaissance Orbiter (MRO) today released a new orbital photo that shows the entire journey on Mars of China’s Zhurong rover, since it landed in May 2021. That image, reduced to post here, is to the right. From the caption, written by Alfred McEwen of the Lunar & Planetary Laboratory in Arizona:

This HiRISE image, acquired on 11 March 2022, shows how far the rover has traveled in the 10 months since it landed.

In fact, its exact path can be traced from the wheel tracks left on the surface. It has traveled south for roughly 1.5 kilometers (about 1 mile). This cutout highlights the rover and the rover’s path (with contrast enhanced to better reveal the tracks).

The white curves that the rover has apparently been inspecting as it moved south are called megaripples, mid-size sand dunes from three to six feet in height that are generally found to be inactive, though not always. From a recent report about Zhurong’s findings:

“The examples Zhurong has visited appear very bright-toned in satellite images taken from orbit, and the team thinks that this is because the megaripples are covered with a layer of very fine dust,” says Matt Balme at the Open University, UK, who wasn’t involved in the analysis. “This means these features are probably currently inactive, as any present-day windblown sand would tend to remove the dust.”

That report used data from the rover’s first sixty days on Mars, after it had passed its first megaripple and had just reached the parachute and backshell. It does not include any later data in the past eight months, as Zhurong rolled past another nine megaripples and several small craters.

It also doesn’t include any data obtained as the rover skirted the wide apron that surrounds the large depression in the lower left. That depression looks like a crater at first glance, but because it appears to be on top of a mound it could instead by an old pitted cone. There are a lot of these cones in this region of the northern lowland plains of Mars, and planetary scientists really want to know whether they were formed from erupting ice, lava, or mud.

The Chinese have so far not released any data on what they have found in these later travels. We shall have to wait for further published papers.

The wider elevation overview map to the right, first published on August 24, 2021 and cropped and annotated to post here, shows Zhurong’s future potential geological targets to the south. The cone to the southwest as well as the nearest scarp to the south are probably the rover’s primary goals.

Though the released results have hinted that the geology here was shaped by both wind and water, direct evidence for water has not been found, or revealed by the Chinese. Zhurong has a radar sensor that could detect evidence of near surface underground ice, if it was there. As far as I know at this point, no results from that instrument have as yet been published.

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Pushback: Pilots sue CDC over Biden mask requirement on planes

12:02 pm

How the CDC determines its mask policies
How the CDC determines its mask policies

Don’t comply: Ten pilots from three different American airlines — American, Southwest, and JetBlue — have now sued the CDC over the Biden administrations mask mandate requiring everyone to wear masks on airplanes.

A group of commercial airline pilots filed a lawsuit against the Centers for Disease Control and Prevention (CDC) in an attempt to lift the federal transportation mask mandate.

In court paperwork, the 10 commercial airline pilots – who work for American JetBlue and Southwest – argued that the CDC issued an order “Requirement for Persons to Wear Masks While on Conveyances & at Transportation Hubs” on Feb. 1, 2020 “without providing public notice or soliciting comment.”

The pilots are asking the court to “vacate worldwide the FTMM (federal transportation mask mandate)” calling the move an “illegal and unconstitutional exercise of executive authority.”

Biden’s edict was first imposed on February 1, 2021, shortly after he took power. It has been extended several times since, the most recent extension keeping it in force through April 18, 2022. At no time, however, has any data been put forth by the CDC demonstrating that the required masks accomplish anything, while we already have decades of data showing that the masks are useless against viruses like the Wuhan flu.

This new lawsuit is the eighteenth filed against the mandate, though it is the first filed by those who work on the planes.

The pilots claim above that the CDC did not follow federal law when it imposed the mandate is almost certainly correct. » Read more

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Alignment of segments in Webb’s primary mirror completed

3:06 pm

Alignment image
Click for full image.

Astronomers and engineers have now successfully completed the alignment of the eighteen segments in the primary mirror of the James Webb Space Telescope.

On March 11, the Webb team completed the stage of alignment known as “fine phasing.” At this key stage in the commissioning of Webb’s Optical Telescope Element, every optical parameter that has been checked and tested is performing at, or above, expectations. The team also found no critical issues and no measurable contamination or blockages to Webb’s optical path. The observatory is able to successfully gather light from distant objects and deliver it to its instruments without issue.

The picture to the right shows that alignment, focused on a single star. As noted in the caption:

While the purpose of this image was to focus on the bright star at the center for alignment evaluation, Webb’s optics and NIRCam are so sensitive that the galaxies and stars seen in the background show up.

After many years delay and an ungodly budget overrun, thank goodness Webb appears to be working better than expected.

It will still be several months before actual science observations begin. Further more precise alignment adjustments need to be done for all its instruments and mirrors.

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Solar scientist Eugene Parker passes away at 94

2:53 pm

R.I.P. Solar scientist Eugene Parker, whose research revolutionized solar science in the 20th century and for which the Parker Solar Probe was named, has passed away at the age 94.

As a young professor at the University of Chicago in the mid-1950s, Parker developed a mathematical theory that predicted the solar wind, the constant outflow of solar material from the Sun. Throughout his career, Parker revolutionized the field time and again, advancing ideas that addressed the fundamental questions about the workings of our Sun and stars throughout the universe.

Parker belonged to the past generations of scientists who followed the principles of the Enlightenment and believed that science was fundamentally the search for truth. He understood he could always be wrong, which brought a certain muscular strength to any ideas he proposed. He could not be lazy in any way, or his work would fail. Instead, it shone, and made what little we know of the Sun today possible.

Sadly, such men are one-by-one going from us. I wonder if the new generations will understand his mindset.

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Recent avalanche on Mars

12:06 pm

Close-up comparison of slump
Click for full image.

Wide view comparison of slump
For full images go here and here.

Cool image time! Today the science team for the high resolution camera on Mars Reconnaissance Orbiter (MRO) released images showing a very recent avalanche, or slumping, on the interior slopes of what looks like a small three-mile-wide crater inside the easternmost reaches of the giant canyon Valles Marineris.

The comparison above, reduced and rotated to post here, is their close-up showing the change, which occurred sometime between March 2021 and February 2022. The wider comparison on the right, cropped, reduced, and annotated by me, shows a wider view to help place this slumping in the context of the crater.

Calling this an avalanche is not really accurate, as it isn’t really the fall of boulders and rocks, but the quick slumping downward of an entire section of what looks like dust or sand. As Alfred McEwen of the Lunar & Planetary Laboratory in Arizona writes in the caption:
» Read more

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NASA extends Ingenuity’s mission through September ’22

9:31 am

Overview map
Click for interactive map.

NASA yesterday officially extended Ingenuity’s flight operations on Mars at least through September 2022, outlining in detail the helicopter’s hoped-for flight targets.

The map to the right shows the helicopter’s present location with the green dot, with its two possible future routes proceeding from this location indicated by dashed lines. The red dot indicates Perseverance’s present location, with its planned route from this spot indicated by the dashed lines.

Scheduled for no earlier than March 19, Ingenuity’s next flight will be a complex journey, about 1,150 feet (350 meters) in length, that includes a sharp bend in its course to avoid a large hill. After that, the team will determine whether two or three more flights will be required to complete the crossing of northwest Séítah.

Once Ingenuity crosses the rough terrain and reaches the delta, it will then be used to do more route scouting for the rover.

Upon reaching the delta, Ingenuity’s first orders will be to help determine which of two dry river channels Perseverance should take when it’s time to climb to the top of the delta. Along with routing assistance, data provided by the helicopter will help the Perseverance team assess potential science targets. Ingenuity may even be called upon to image geologic features too far afield (or outside of the rover’s traversable zone), or perhaps scout landing zones and caching sites for the Mars Sample Return program.

This ambitious plan exists because both the helicopter and its engineering team have far exceeded expectations. At the moment, there is no obvious reason why Ingenuity cannot continue to operate for years, an expectation that no one predicted.

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Mark Vande Hei sets new record for longest American space flight

10:03 am

Mark Vande Hei today set a new record for the longest American space flight, exceeding the 340 days flown by Scott Kelly on ISS in 2012-2013.

Since Vande Hei is scheduled to return to Earth on March 30th, his total record flight time should end up being 355 days, just short of a full year.

Vande Hei arrived at the space station aboard a Russian Soyuz spacecraft on April 9, 2021, knowing at the time that he would be there for at least for the five to six months that is typical today for expedition crew members. His mission was extended by NASA in September to allow for a Russian movie crew to visit the orbiting complex and, more importantly, protect against a crew rotation schedule that could leave the station without any Americans on board.

Vande Hei’s record will be the fifth longest, behind four other Russians on Mir. Musa Manarov and Vladimir Titov were the first to complete a year long flight in 1987-1988. Valery Polyakov holds the record for the longest flight, 437 days in 1994-1995. Sergei Avdeyev’s flight of 381 days on Mir in 1998-1999 is the second longest.

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Mesa in the Martian northern lowlands

3:21 pm

Mesa in the dry northern lowlands
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken on February 2, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and shows a mesa sticking up on the relatively flat and featureless northern lowland plains in Utopia Planitia, the second largest impact basin on Mars.

The full image shows three such mesas. Though pictures taken in the northern lowlands of Utopia tend to show evidence of buried ice or glaciers, the impression I get from this picture is one of dryness. If there is any ice here, it is below ground. And even that seems unlikely. The surface surrounding nearby craters does not have that squishy and slushy look that is seen in the north when an impact occurred on near surface ice. Instead, the ground looks solid.

The overview map below reinforces this impression.
» Read more

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Supernova discovered in Cartwheel galaxy

8:54 am

Cartwheel Galaxy, before and after supernova
Click for full image.

Cool image time! In reviewing a December 2021 image of the Cartwheel Galaxy taken by the New Technology Telescope in Chile, astronomers noticed something that was not there in earlier images, a new supernovae.

The photo above, reduced to post here, compares a 2014 image, taken by the Very Large Telescope, with the 2021 photo. In the lower left of the new image is a bright object not in the previous photo.

This event, called SN2021afdx, is a type II supernova, which occurs when a massive star reaches the end of its evolution. Supernovae can cause a star to shine brighter than its entire host galaxy and can be visible to observers for months, or even years — a blink of an eye on astronomical timescales. Supernovae are one of the reasons astronomers say we are all made of stardust: they sprinkle the surrounding space with heavy elements forged by the progenitor star, which may end up being part of later generations of stars, the planets around them and life that may exist in those planets.

Cartwheel is about 500 million light years away, and because of its bright outer ring is one one of the more unusual nearby galaxies.

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Ingenuity completes 21st flight on Mars

3:54 pm

Overview map
Click for interactive map.

According to a tweet today from JPL, the Mars helicopter Ingenuity has successfully completed its 21st flight on Mars, traveling 1,214 feet in two minutes and nine seconds at an average speed of 12.6 feet per second.

The red dot on the map to the right shows Perseverance’s location as of today. The green dot indicates Ingenuity’s position before the 21st flight. Since neither the Perseverance nor the helicopter teams have posted any updates describing the 21st flight, it is difficult to indicate a precise location for its landing site. All we know is that the helicopter is supposed to fly to the northwest, cutting across the rougher region while the rover follows the tan dotted line around that rough region, with both targeting the delta to the northwest.

As a guess, I have placed a black dot about 1,200 feet to the northwest.

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More thumbprints on Mars!

1:22 pm

Thumbprints on Mars
Click for full image.

Cool image time! Among the many strange and unexplained geological features that scientists have identified on Mars, the thumbprint feature is one of the most intriguing. The photo to the right, cropped and reduced to post here, is a fine example, and was taken on September 10, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The thumbprints are the lighter splotches, and are generally found near curved ridges located mostly in Martian lowlands. All appear to have crater-like features in them, though these craters are not impact craters, but likely (though not confirmed) caused by some form of underground eruption, be it mud, ice, lava or something else. Though scientists do not yet really understand the process that formed the thumbprints, the data strongly suggests that they formed in connection with glacial events. From this 2003 paper [pdf]:

TT [thumbprint terrain] as well as the associated trough systems were formed by a glacial mechanism. [Elevation] data show that the trough systems consistently lie topographically above the TT; this implies that if they were they formed by the same glacier, the troughs must have formed before the glacier retreated and formed the TT.

The splash apron around the crater near the bottom of the photo supports the glacial theory, implying the presence here of underground ice.

Scientists have also theorized wind processes and cinder cones as explanations for these features.

These particular thumbprints are located, as shown in the overview map below, in the same general area as a previous cool image of thumbprints, from April 2019.
» Read more

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Monitoring one glacier flowing off a mesa in Mars’ glacier country

1:28 pm

Vicous glacial flow on Mars
Click for full image.

Today’s cool image takes us back to the mesa in Mars’ glacier country that first clued me in on the prevalence of ice in the Martian mid-latitudes. The photo to the right, rotated, cropped, and reduced to post here, was taken on November 13, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a viscous flow coming down from a hollow on that mesa’s southern wall.

The new image has likely been taken to see if anything has changed since the previous image was taken in 2014. Based on the resolution published at the MRO website, nothing seems to have changed, though with more sophisticated software higher resolution versions of the images are available that might show some changes.

In my first post about Mars’ glacier country in December 2019, this flow was one of four that I featured coming off this same 30-mile wide mesa, as shown by the first overview map below.
» Read more

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Fractured terrain on Mars

1:39 pm

Fractures on Mars
Click for full image.

Today’s cool image, which at first glance does not seem so puzzling, actually falls into my “What the heck?” category of baffling Martian geology. The picture to the right, cropped and reduced to post here, was taken on January 15, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled “Avernus Cavi fractures”, it shows what resembles the well-documented chaos terrain seen in many places on Mars, where erosion over eons along fault lines creates mesas with random criss-crossing canyons.

The problem is that this location is practically on the Martian equator, and chaos terrain tends to be found in the mid-latitude bands where there are many glaciers, suggesting the cyclical waxing and waning of those glaciers is what causes the erosion. Here at the Martian equator the terrain is very dry. No glaciers.

Moreover, note the higher mesa near the top center. Its flat top suggests that once this terrain was covered with an even higher layer of material, almost all of which was stripped away evenly everywhere, except where that mesa sits. As an amateur geologist I can’t think of any sequence of events that would do such a thing. I suspect professionals might have problems themselves.

Then there are the small parallel ridges. They suggest dunes, especially inside the depressions where sand and dust can get trapped. On the mesa tops however these ridges are more mysterious. Why for example are they aligned with the small ridge in some hollows, but not others? They in many ways remind me of the ridges in this earlier “What the heck?” cool image, also right on the equator.

The overview map below provides some help, though not much.
» Read more

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The layered Martian history exposed in Valles Marineris

12:28 pm

Overview map

The layers in Valles Marineris
Click for full image.

Cool image time! Like the Grand Canyon in the United States, Mars’ largest canyon, Valles Marineris, appears to have been carved out of a layered terrain, thus exposing those many layers in the walls of the canyon.

Valles Marineris, however, is much much larger than the Grand Canyon. You could fit dozens of Grand Canyons inside it and hardly fill it. Yet, its walls have the same layered look, suggesting that in Mars’ long geological history, first came many events that laid down new layers time after time, followed by a long period when the laying ceased and other events carved out the canyon to its almost 30,000 foot depth (which by the way is also about six times deeper than the Grand Canyon).

Today’s cool image to the right, cropped and reduced to post here, was taken on September 5, 2021 and shows a terraced terrain on the floor of Candor Chasma, one small side canyon of Valles Marineris that is still much larger than the Grand Canyon. The black dot in the overview map above indicates its location. I roughly estimate the elevation difference between the high and low spots in the picture is about 3,000 feet, a difference that while two-thirds that of the depth of the Grand Canyon is almost unnoticeable within the depths of Valles Marineris.

This layering is probably the canyon’s most important geological feature. See these previous cool images here and here for other examples. When geologists finally arrive on Mars and can begin dating these layers in detail they will likely reveal the planet’s entire geological history, going back five to six billion years.

Most of the layers are probably volcanic flood lava laid down by repeated eruptions from the giant volcanoes to the west. In between and within however will be deposits from the Martian atmosphere, telling us its composition and thickness. All told, the layers of Valles Marineris will likely unlock almost all of the most basic secrets of Martian geology.

We merely have to go there to find out.

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Martian crater overwhelmed by glacier?

1:32 pm

Martian crater overwhelmed by glacier?
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on January 28, 2022 by the high resolution camera on Mars Reconnaissance Orbiter. It shows what the science team labels a “modified crater.”

What I see is an old crater almost completely covered by glacial material. That material however is also very old, as there are numerous small craters on its surface, enough that it must have been here for a long time. Its cracked surface also suggests this glacier is very old.

Thus, while we might have ice here, buried by a thin layer of dust and debris to prevent it from sublimating away, it must be very old ice. The many climate cycles caused by the extreme swings in Mars’ rotational tilt, from 11 to 60 degrees, have apparently not caused this ice to ebb and flow very much.

Might it therefore not be ice, but hardened lava?

The location, as shown by the overview map below, provides some context, but only makes this mystery more puzzling.
» Read more

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Sunspot update: The Sun rages on

10:54 am

Time for my monthly sunspot cycle update, where I take NOAA’s monthly graph showing the long term trends in the Sun’s sunspot activity, and annotate it with additional data to provide some context.

The trend of sunspot activity exceeding the predictions continued in February. While the increase in activity from January still left it less than the activity in December, the total number of sunspots is still far above the number predicted by NOAA’s panel of solar scientists in 2020, with the rise towards a solar maximum also much steeper and far faster than predicted.
» Read more

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Germany turns off its instrument on the Spektr-RG orbiting X-ray telescope

8:59 am

As part of Germany’s decision to break off all scientific cooperation with Russia in response to Russia’s Ukraine invasion, the Max Plank Institute has turned off its instrument on the Spektr-RG orbiting X-ray telescope.

Meanwhile, Roscosmos’ head, Dmitry Rogozin revealed he will demand compensation from Europe for its sanctions, including this shut down on Spektr-RG.

Europe’s sanctions cause real losses to Russia’s space corporation Roscosmos. The corporation will estimate them and demand a compensation from partners in Europe, Roscosmos’s press-service told TASS on Tuesday. “They have caused harm to the Spektr-RG laboratory’s research program by turning off one of the two telescopes. Their sanctions cause real losses to us. The damage will be estimated and a bill presented to the European side,” Roscosmos said.

It now appears that all the European cooperation with Russia in space is likely dead, at least until Russia gets out of the Ukraine.

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The Democrats now prove there never was any science behind their mandates

12:21 pm

Most of all beware this boy.’
As noted by the Spirit of Christmas Present in Dickens’
The Christmas Carol, ‘This boy is ignorance, this girl is want.
Beware them both, but most of all beware this boy.’

Only months and years after most Republican Party governors and politicians had lifted or halted all mandates requiring masks or COVID shots or social distancing, in the past week Democrats in numerous places have suddenly decided that masks and COVID shots and social distancing have suddenly become unnecessary or ineffective, and have canceled almost all their government-edicts mandating such things.

Simultaneously, the CDC late last week finally loosened its mask recommendations, no longer demanding that Americans wear masks indoors or in many other circumstances.

What none of these announcements mentioned was any evidence of any new scientific results to justify the new recommendations or the loosening of mandates. These changes were based — not on new scientific results — but on the fear-based opinions of politicians and health bureaucrats who for the past two years have consistently based their edicts and mandates solely on emotions and politics, not scientific evidence, and were repeatedly wrong every single time.

That they happened to be correct now is not because they are basing their actions on any new”science”, but like a broken clock, even idiots can stumble on the truth once in awhile, by accident.

In this case however their stumbling is not entirely by accident. » Read more

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Scientists: Yutu-2 spots tiny glass globules similar to those found by Apollo astronauts

9:45 am

According to a paper just published Chinese scientists running the Yutu-2 rover on the far side of the Moon have spotted several tiny glass globules similar to those found by Apollo astronauts.

Xiao and his team believe the small spheres, which are between 0.59 and 0.79 inches (1.5 to 2.5 centimeters) across, were probably formed by relatively recent meteor impacts. Specifically, the researchers believe that the globules formed from anorthosite, a volcanically-formed rock rich in the mineral feldspar, after a high-energy impact melted the rock and reformed into spheres.

In appearance these Yutu-2 globules appear translucent, unlike the Apollo globules which were either dark or opaque. Since the rover did not do spectroscopy on these objects before moving on, however, their actual make-up is unknown, with the speculations by the researchers above merely that, speculations, though reasonable.

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Chandra’s camera remains in safe mode

12:12 pm

Though engineers have improvised a work-around that has allowed most of instruments on the Chandra X-Ray observatory to resume science operations, the power supply problem in the telescope’s high resolution camera (HRC) that occurred on February 9th remains unresolved, leaving that camera in safe mode.

The Chandra science instrument and engineering teams continue to analyze the cause of the HRC power supply issue, as well as potential approaches to enable the HRC again. The spacecraft is otherwise healthy and operating normally.

Chandra has been flying now for more than two decades, well past its original mission. For it to begin to have these problems is not surprising, though it will be a great tragedy if it fails just as the James Webb Space Telescope is about to go operational. Ideally astronomers want data from both, as well as Hubble, to cover a wide swath of the electromagnetic spectrum, from the optical to the infrared to X-rays.

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Ingenuity’s 20th flight a success

7:59 pm

According to a tweet released tonight by JPL, the 20th flight of Ingenuity on Mars was a success, lasting 130 seconds and traveling about 1,283 feet.

The tweet includes a short video showing the helicopter taking off and then landing, at the same spot, which I am sure is not of this flight but from a previous test that simply went up and down. The flight just completed took off and headed mostly to the north, slightly west, and landed in a different spot entirely.

Expect more information to follow.

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Scientists: Martian topography in one region suggests the past existence of lakes and river networks, but not a large single ocean

3:53 pm

Based on a just published paper, scientists using orbital topography data and imagery have concluded that more than three billion years ago on Mars ancient rivers in the transition zone between the southern cratered highlands and the northern lowland plains fed into numerous lakes in the lowlands, not a single large ocean as some scientists posit.

From their abstract:

The northern third of Mars contains an extensive topographic basin, but there is conflicting evidence to whether it was once occupied by an ocean-sized body of water billions of years ago. At the margins of this basin are the remnants of deltas, which formed into water, but the size and nature of this water body (or water bodies) is unclear, and detailed investigations of different regions of the basin margins are necessary.

In this study, we use high-resolution image and topographic datasets from satellites orbiting Mars to investigate a series of water-formed landforms in the Memnonia Sulci region, set along the boundary of Mars’s northern basin. These landforms likely formed billions of years ago, providing evidence for ancient rivers and lakes in this region. The geologic evolution of these rivers and lakes was complicated, likely influenced by water-level fluctuations, changes in sediment availability, and impact cratering. Our topographic analysis of these rivers and lakes suggests that they terminated in a series of ancient lake basins at the boundary of Mars’s northern basin, rather than supplying a larger, ocean-sized body of water. [emphasis mine]

Overview map

The Memnonia Sulci region is in the cratered highlands just south of the Medusae Fossae Formation, the largest volcanic ash deposit on Mars. The region of study in it is marked by the blue dot in the overview map to the right.

The study does not preclude the possible existence of a northern ocean on Mars, but it says that at least in this region at the equator, it did not exist. Instead, the various river valleys drained into separate smaller and relatively short-lived lakes.

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Curiosity images the Martian version of a cave formation

10:00 am

An helictite on Mars?
Click for full image.

Cool image time! The photo to the right, cropped and reduced to post here, was taken today by Curiosity’s Mars Hand Lens Imager (MAHLI), a camera designed to get close high resolution images of very small features on the surface.

The Curiosity image site does not provide a scale, but MAHLI, located at the end of the rover’s robot arm, is capable of resolutions as small as 14 microns per pixel. Since a micron is one thousandth of a millimeter, and the original image was 1584 by 1184 pixels in size, that means the entire image is likely only slightly larger than 18 to 25 millimeters across, or slightly less than an inch.

This feature, which closely resembles a cave helictite, is thus about a quarter inch in size. Helictites, which in caves often resemble wildly growing roots, are nonetheless made of calcite, not organic material. They grow wildly because the water is being pushed out from their center is under pressure, so that as it drips away from the formation it leaves its calcite deposits randomly, causing the formation to grow randomly.

MAHLI also took what looks to be an infrared or heat image of the formation, which appears to show that the tips of the branches are at a different temperature, I think cooler, than the rest of the formation.

While seeping water causes helictites on Earth, what formed this thing on Mars is beyond my guess. It sure looks cool however.

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Ingenuity update: Dust storm caused issues; 20th flight upcoming

9:43 am

Overview map
Click for interactive map.

According to the Ingenuity engineering team in an update today, the Mars helicopter is getting ready for its 20th flight, scheduled for no earlier than today, even as the team successfully dealt with dust that settled on the helicopter’s various parts prior to flight 19.

The dust storm did, however, leave the Ingenuity team with two additional challenges to deal with: a dirty navigation camera window and dust in the swashplate assemblies.

Comparing navigation camera images taken before and after the dust storm revealed that the storm deposited debris on the ground-facing navigation camera window, specifically around the periphery of the camera’s field of view. Debris on the navigation camera window is problematic because Ingenuity’s visual navigation software may confuse the debris with the actual ground features that it tries to track during flight, which can cause navigation errors. Fortunately, Ingenuity’s software provides a tool for dealing with this issue: The team can provide an updated image mask file that tells the visual navigation software to ignore certain regions of the image. The operations team made use of this feature and performed an image mask update late last month.

The dust storm also deposited dust and sand in Ingenuity’s swashplate assemblies. On Mars as well as on Earth, a helicopter’s swashplates are very important because they control the pitch (angle from horizontal) of the rotor blades, which is essential for stable and controlled flight. Ingenuity’s swashplate issue was first detected when the rotorcraft reported a failure during its first automated swashplate actuator self-test since the dust storm on Jan. 28, 2022 (Sol 335 of the Perseverance mission). Data revealed that all six swashplate servo actuators were experiencing unusual levels of unusual levels of resistance while moving the swashplates over their range of motion.

The engineers subsequently tested a procedure, planned before launch, for cleaning the swashplates, and found that it worked.

The data from that activity showed a significant improvement – a reduction in servo loading, so the team followed it up with seven back-to-back servo wiggles on Sol 341. Remarkably, by the end of that activity, Ingenuity’s servo loads appeared nearly identical to nominal loads seen prior to the dust storm.

After dealing with both dust issues, flight 19 proceeded successfully, as planned.

The overview map above shows the present location of Perseverance as the red dot, the present location of Ingenuity by the green dot, and the approximate landing site for the helicopter’s 20th flight by the black dot. The tan dotted line shows Perseverance’s planned route.

Perseverance itself has been traveling fast since Ingenuity’s last flight on February 9th, almost completely retracing its steps to return almost to its landing site.

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Dry barren ground in Martian northern lowlands?

3:38 pm

Dry barren ground in the Martian northern lowlands?
Click for full image.

Today’s cool image is intriguing because of what appears to not be there, rather than what is there. The photo to the right, cropped and reduced to post here, was taken on November 3, 2021 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

At first glance it appears to show a very dry, barren surface. At its base are many parallel grooves running from the southwest to the northeast. On top of these grooves are several more recent crater impacts, as well as several patches of higher bedrock that appears to have been hard enough to resist whatever erosion process caused the groves.

Yet, based on the overview map below, the location of this photo should not be dry and barren, but instead home to a near-surface ice sheet covering everything.
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Curiosity’s coming travels across the rocky Greenheugh Pediment

10:31 am

Curiosity's view west on February 21, 2022 (Sol 3393)
Click for full resolution panorama. Original images can be found here, here, and here.

Overview map
Click for interactive map.

Curiosity, having successfully climbed up and out of Gordon Notch, was able to aim its navigation cameras forward yesterday and get its first views from this position across the very rocky Greenheugh Pediment to its next major goal, Gediz Vallis Ridge. The panorama above, taken by the rover’s right navigation camera, shows this view. The ridge is about 1,500 feet away, at its closest point. The rim of Gale Crater, barely visible in the haze, is about 20-30 miles away.

The overview map to the right indicates the area covered in this panorama by the yellow lines. The red dotted line indicates Curiosity’s planned future route.

Curiosity’s first view of the pediment was made in March 2020, from a point on its northern border, just beyond the top edge of the map. The panorama taken then showed what appeared to be a very treacherous and rough surface, possibly too rough for Curiosity to traverse.

According to the science team’s most recent update from before the holiday weekend, the plan had been to spend February 19-20 studying the ground, then drive a short distance yesterday to get a better view ahead.

This will give us a good vantage point to look into the valley ahead and try to scope out our future route. … We chose to drive about 10m total, in order to get the rover oriented at a good heading and parked in a good spot. We expect a similarly beautiful view from our post-drive imaging.

That view is the panorama above. Though still very rough, the ground ahead appears far more traversable than the surface seen in 2020.

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Have astronomers found an exoplanet with raining metal and gems?

9:33 am

The uncertainty of science: Using data from the Hubble Space Telescope, astronomers think they have detected on a hot Jupiter exoplanet 880 light years away the formation of clouds and rain made up metals and gems.

The exoplanet is tidally locked so that one side always faces its star, which also means the temperature difference between the two hemispheres is gigantic, 5,400 degrees Fahrenheit on the dayside and about 2,600 degrees on the nightside.

Previous Hubble data showed signs of metals including iron, magnesium, chromium and vanadium existing as gasses on the planet’s dayside. But in this study, the researchers have found that on the planet’s nightside, it gets cold enough for these metals to condense into clouds.

And, just as the strong winds pull water vapor and atoms around the planet to break apart and recombine, metal clouds will blow to the planet’s dayside and evaporate, condense back on the nightside and so on.

But metal clouds aren’t the only strange phenomenon these researchers spotted on this hot Jupiter. They also found evidence of possible rain in the form of liquid gems.

While tantalizing and alien, these results have many uncertainties. What the data suggests might not be the reality. To find out more, the astronomers hope to use the James Webb Space Telescope to do more infrared observations, once it becomes operational.

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