Tag: science

More hiking possibilities on Mars!

2:21 pm

More hiking possibilities on Mars
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on September 27, 2023 by the high resolution camera on Mars Reconniassance Orbiter (MRO). Dubbed a “terrain sample” by the science team, this picture was likely chosen not as part of any specific research project but to fill a gap in the camera schedule so as to maintain that camera’s proper temperature.

When the team needs to do this they try to pick interesting targets. In this case the location is the region of many many parallel north-south fissures that extend for more than 800 miles south of the giant but relative flat shield volcano Alba Mons. These fissures are grabens, cracks formed when underground pressure pushed the ground up and caused it to spread and crack.

What attracted me to this picture is the ridgeline. It struck me as a wonderful place to hike. I have even indicated in red the likely route any trail-maker would pick to go from the valley below up onto the ridge, and then along its knifelike edge to the south. The height of the cliff down to the east valley averages about six hundred feet, guaranteeing beautiful scenery the entire length.
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A galaxy with a tail of star-forming clusters

10:34 am

A galaxy with a tail of newborn stars
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Cool image time! The picture to the right, reduced and sharpened to post here, was taken by the Hubble Space Telescope as part of a survey of twelve different galaxies that have long tails. In this case, the galaxy is named Arp-Madore 1054-325, and the tail that trails off in the upper left is caused by the gravity of the nearby neighboring galaxy, which I think is the patch of stars just below it. Within it are many star clusters where new stars are forming. From the caption:

A team of astronomers used a combination of new observations and archival data to get ages and masses of tidal tail star clusters. They found that these clusters are very young — only 10 million years old. And they seem to be forming at the same rate along tails stretching for thousands of light-years. “It’s a surprise to see lots of the young objects in the tails. It tells us a lot about cluster formation efficiency,” said lead author Michael Rodruck of Randolph-Macon College in Ashland, Virginia.

Before the mergers, the galaxies were rich in dusty clouds of molecular hydrogen that may have simply remained inert. But the clouds got jostled and bumped into each other during the encounters. This compressed the hydrogen to the point where it precipitated a firestorm of star birth.

In some ways this galaxy portends one possible future of the Milky Way, after it collides with the nearby Andromeda galaxy in the far future.

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Scientists: We think the Saturn moon Mimas may have a young underground ocean

8:45 am

The uncertainty of science: Using computer modeling based on orbital data obtained from the orbiter Cassini, scientist now believe the Saturn moon Mimas may have a young underground ocean.

[I]n 2014, a team that included Lainey and that was led by Radwan Tajeddine, an astronomer then at the Paris Observatory, analysed images taken by NASA’s Cassini spacecraft, which explored Saturn and its moons between 2004 and 2017. By studying how the 400-kilometre-wide Mimas wobbled in its orbit around Saturn, the researchers concluded that it had either a buried ocean or a rugby-ball-shaped core. As more scientists studied how an ocean could have formed and evolved, it became harder to explain the geology of Mimas without invoking an ocean.

In the 2024 study, Lainey and his colleagues seem to have nailed the case. They went further than they had in 2014, by analysing not just the orbit’s wobble but also how Mimas’s rotation around Saturn changed over time. The team combined Cassini observations with simulations of Mimas’s interior and its orbit to conclude that there must be an ocean 20–30 kilometres below Mimas’s surface.

The journal Nature published the paper, and the link above goes to an article in Nature describing the results, with a headline “The Solar System has a new ocean — it’s buried in a small Saturn moon.” This is very poor journalism, but very typical these days from Nature. Nowadays that journal routinely pushes the results it publishes with great certainty, even if the data is quite uncertain.

And these results are quite uncertain. They are based on computer simulations using orbital data only. No data from Mimas itself is involved. While that orbital data and computer models might suggest an underground ocean that is very young, that is the best it does, “suggest.” Without question this conclusion is very intriguing, but it should not be treated as a discovery, only a theory that still needs confirmation with much better data.

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A small Martian volcano?

12:35 pm

A small Martian volcano?
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on December 21, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled it a “fresh crater”, but that description I think is misleading, as it implies a recent impact.

The crater does not look like a fresh impact crater to me. Such things on Mars usually appear very dark, as the impact dredges up dark material. This crater is not dark. More significant is the crater itself. The small 300-foot-wide inner crater, surrounded by a circular plateau and all sitting inside the larger 1,200-foot-wide crater is completely unique compared to any impact crater I have ever seen. Impacts in soft material, such as ice-impregnated ground, can cause concentric ripple rings, but they don’t look like this.

Instead, this crater more resembles the caldera of a volcano, where subsequent eruptions can produce overlapping depressions at the volcano peak. (See for example this picture of Olympus Mons.)

Moreover, the crater sits on top of a peak approximately 300 feet high. While impacts in ice-impregnated ground on Mars can produce splash aprons as seen here, the crater usually sits at about the same elevation as the surrounding terrain, not at the top of a peak. This peak suggests the apron was forned not by a splash but repeated flows coming down from the top.
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Computer problem on Voyager-1 remains unsolved

9:54 am

Engineers remain baffled over a computer issue that has prevented the receipt of any data since November 2023 from Voyager-1, floating some 15 billion miles away just outside the solar system in interstellar space.

In November, the data packages transmitted by Voyager 1 manifested a repeating pattern of ones and zeros as if it were stuck, according to NASA. Dodd said engineers at JPL have spent the better part of three months trying to diagnose the cause of the problem. She said the engineering team is “99.9 percent sure” the problem originated in the FDS [Flight Data Subsystem], which appears to be having trouble “frame syncing” data.

So far, the ground team believes the most likely explanation for the problem is a bit of corrupted memory in the FDS. However, because of the computer hangup, engineers lack detailed data from Voyager 1 that might lead them to the root of the issue. “It’s likely somewhere in the FDS memory,” Dodd said. “A bit got flipped or corrupted. But without the telemetry, we can’t see where that FDS memory corruption is.”

Since November the only signal received from Voyager-1 is a carrier signal that simply tells engineers the spacecraft is alive. Though the effort continues to try to fix the spacecraft, the odds of bringing it back to life are becoming slim, especially because its power supply will run out in 2026 at the very latest. Even if they manage to fix the issue now, the spacecraft has only a short time left regardless.

Considering the computers on this spacecraft, as well as its twin Voyager-2, have been operating continuously for almost a half century since their launch in 1977, their failure now is nothing to be ashamed of. The engineers that built both did well, to put it mildly.

As for Voyager-1’s future, even dead it will fly on into interstellar space, eventually getting within 1.5 light years of a star in the constellation Camelopardalis.

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Curiosity’s damaged wheels continue to appear stable despite the rough Martian terrain

12:27 pm

A new look at Curiosity's worst wheel
To see the original images, go here and here.

The rover Curiosity on Mars has for more than two years been traveling across a very rocky and rough terrain as it climbs higher and higher on Mount Sharp inside Gale Crater. Since the rover’s wheels experienced far more damage than expected early in its mission, when it was on the floor of the crater where the terrain was not as severe, engineers have adopted a whole range of techniques to try to reduce any further damage.

First, they increased the safety margins on the software that guides Curiosity. It picks its way very carefully through the rocks, and stops immediately if it finds itself crossing terrain that is too rough.

Second, the science team does a photo survey of the wheels after every kilometer of travel. The two pictures to the right compare the damage on the rover’s most damaged wheel, with an image from the previous survey on top and the most recent image, taken yesterday, on the bottom. I have numbered the same treads, called grousers, in the two images to make it easier to compare them.

As you can see, it does not appear as if the damage has increased in the 210 sols or seven months of travel since the last survey. This wheel looks bad, but it is the worst wheel on the rover, and the strategies that the engineering team adopted years ago to reduce further damage continue to work, even as Curiosity traverses some very rough ground.

The software requires the rover to travel shorter distances in each drive when the ground is this rough, but the consequence is that it will last much longer, and thus have a better chance of reaching higher elevations on Mount Sharp.

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Perseverance snaps its first picture of grounded Ingenuity

10:25 am

Overview map
Click for interactive map.

Ingenuity on dune, as seen by Perseverance on February 4, 2024
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Perseverance on February 4, 2024 finally moved into a position where it was close enough to take its first picture of the now grounded Ingenuity helicopter. That picture, cropped, reduced, and enhanced to post here, is to the right, taken by the rover’s left high resolution camera. You can see Ingenuity sitting on the slope of a dune near the upper right.

The overview map above provides the context. The green dot marks Ingenuity’s final resting spot. The blue dot marks Perseverance’s present location, with the yellow lines indicating approximately the area covered by the photo.

Whether the rover is now close enough to get good imagery for a final engineering test of Ingenuity — where its rotors will be rotated and shifted slowly to determine the extent of the propeller damage — is not clear. Perseverance could move much closer, but its science team might not want to cross these dunes out of fear the rover would get stuck. They might move forward a few more feet, to the top of the south bank of Neretva Vallis, before doing that test.

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Juno completes its closest approach of the Jupiter moon Io

9:53 am

Io on February 3, 2024
Click for full image.

The Jupiter orbiter Juno successfully completed its 58th close fly-by of the gas giant, during which it also made its closest approach to the volcanic moon Io, zipping past at a distance of 932 miles. The image of Io to the right, cropped and reduced to post here, was taken at that closest Io approach, and shows a mountain on the horizon as well as a large shield volcano in the center (the dark splotch), with a major lava flow to the south. The picture was processed by citizen scientist Brian Swift.

Another image, processed by Björn Jónsson, shows the differences at one volcano dubbed Loki between the December 30, 2023 and the February 3, 2024 flybys. It appears that the brightness of the apron of lava that surrounds the volcano changes significantly depending on the lighting and the angle of view. In December it was almost black. In February it was greyish silver, almost shiny.

Another image, processed by Andrea Luck, captured faint eruption plumes on Io’s edge, caused by an ongoing eruption just beyond the horizon.

Juno still has four more flybys of Io coming up, but none will be as close as the February 3rd approach.

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Asteroid that landed near Berlin found and identified

3:07 pm

The meteorite that crashed near Berlin late last month, only hours after being spotted in space, has now been found and identified.

“We only spotted the meteorites after a Polish team of meteorite hunters had identified the first find and could show us what to look for,” said Jenniskens. “After that, our first finds were made quickly by Freie Universität students Dominik Dieter and Cara Weihe.”

The meteorites are fragments of the small asteroid 2024 BX1, first spotted with a telescope at Konkoly Observatory in Hungary by astronomer Dr. Krisztián Sárneczky, tracked and then predicted to impact Earth’s atmosphere by NASA’s Scout and ESA’s Meerkat Asteroid Guard impact hazard assessment systems, with Davide Farnocchia of JPL/Caltech providing frequent trajectory updates, and finally causing a bright fireball that was seen and filmed. This was Jenniskens’ fourth guided recovery of such a small asteroid impact, following a 2008 impact in Sudan, a 2018 impact in Botswana, and a 2023 impact in France.

Today, Jenniskens’ collaborators at the Museum für Naturkunde officially announced that the first examinations of one of these pieces with an electron beam microprobe prove the typical mineralogy and chemical composition of an achondrite of the aubrite type.

Aubrite meteorites are rare and hard to find, so this discovery is important.

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The failure of the COVID jab and the people who pushed it

2:42 pm

Sudden collapse
One of many sudden public collapses.
Click for full video.

I think it is time to do an update on the recent research outlining the disaster that the mRNA COVID jab has brought to humans worldwide. The news has generally been bad, though sadly none of it has been a surprise to anyone paying attention since 2021 and 2022.

Note to that no where in any of my reporting do I ever call these shots “vaccines.” In the past, when you got a vaccine it protected you from the targeted disease. The jab does not do that. It is not even clear that it reduces your chances of catching the disease, with significant evidence actually suggesting it increases your chances.

We begin with a study published in August 2023 that found that the jab appeared to damage the immune system of children.

Kids who got Pfizer’s mRNA Covid jabs had a weakened immune response to other viruses and bacteria, Australian researchers reported in a study published last week. The diminished response appeared within weeks after the second Pfizer dose, the authors found. Blood taken from the children produced fewer crucial signaling molecules when stimulated with several common potential bacteria and viruses.

Over time, the immune response to bacteria returned to normal. But the diminished response to viruses lasted at least six months, for as long as the researchers collected data.

This study was small, involving only 29 kids, but the data was “troubling” to all researchers involved, and demanded further research.

Then in September a study of health care workers found that getting the jab actually made them sicker.
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A spot where the surface of Mars cracked

1:22 pm

The spot where Mars cracked
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on September 14, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small section of the Cerberus Fossae cracks, a parallel series of cracks that stretch more than 700 miles across the volcanic plains of Mars.

These cracks formed when the ground spread apart, creating a void in which the surface collapsed. You can see this process illustrated quite clearly by the crater in the lower right, as indicated by the arrow. The crater had existed prior to the crack. When the ground split and collapsed, only the northeast quadrant of the crater was destroyed.

These cracks might also have been the source of Mars’ most recent large volcanic event, as shown by the overview map below.
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Curiosity looks ahead at very rough terrain higher on Mount Sharp

10:00 am

Panorama on Sol 4086, February 3, 2024
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The rough terrain higher on Mount Sharp
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Cool image time! The picture to the right, reduced and enhanced to post here, was taken on February 3, 2024 by the high resolution camera on the Mars rover Curiosity. The area it covers is indicated by the rectangle on the panorama above, which has been cropped, reduced, and enhanced to post here. That panorama was created from 46 photos taken by the rover’s right navigation camera on that same day.

Those rough small peaks are higher on Mount Sharp, though far below its summit. The summit itself is not visible, and in fact has never been visible to Curiosity since it landed on Mars in August 2012. The peak is about 26 miles to the south and about 16,000 feet higher up, with much of the mountain in the way.

These small, rough peaks are in an area that the rover will likely never go, as shown in the overview map below.
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Sunspot update: The Sun in January acted like solar maximum is here

11:11 am

In my monthly sunspot update at the start of January, I asked in the headline “Are we now in the next solar maximum?”

The Sun’s sunspot activity in January since then has apparently answered that question. NOAA this week posted its monthly update of its graph showing solar sunspot activity on the Sun’s Earth-facing hemisphere, and as I do every month since 2011, I have posted that graph below, with annotations to provide a larger context.
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One last engineering test planned for Ingenuity

9:23 am

Engineers plan to do one last engineering test with Ingenuity, slowly rotate its propellers while collecting imagery, likely from both the helicopter and Perseverance.

Teddy Tzanetos, Ingenuity Project Manager, said that NASA and JPL still aren’t sure what caused the damage to Ingenuity’s blades; it remains unclear whether the helicopter’s power dipped during landing, causing unwanted ground contact, or if it accidentally struck the ground to cause a “brownout.”

Tzanetos added that NASA and the Jet Propulsion Laboratory (JPL) will slowly rotate the helicopter’s blades and “wiggle” them, or adjust their angle, while collecting video in order to allow the team to determine the extent of Ingenuity’s damage. However, Tzanetos said that no matter what such imaging will show, the dual-rotor drone has flown its last flight and will soon end its mission.

This test will likely not occur until Perseverance gets into a position where it can film the test also. The helicopter’s cameras look downward, so all it will be able to photograph is the shadow of those blades as they move. Perseverance can look directly at it, and if it gets into a position slightly higher than Ingenuity it can get a good viewing angle down at the blades.

At the moment the rover is about a thousand feet to the east, though steadily working its way towards it.

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A soft but dim spiral

10:51 am

A soft but dim spiral
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope as part of a survey of nearby galaxies in which supernovae had previously been detected.

This softly luminous galaxy — lying in the constellation Hercules, about 110 million light-years from Earth — seems outshone by the sparkling foreground stars that surround it. The type II supernova which took place in this galaxy in 2019, while no longer visible in this image, definitely outshone the galaxy at the time!

What amazes me about this somewhat dim spiral galaxy is its beautiful structure, its two spiral arms coiling outward in perfect symmetry. And yet, we are looking at a object that is almost entirely empty space, hundreds of thousands of light years across. Somehow the almost infinitesimal force of gravity at those distances is still able to shape the arms, and the spirals.

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Another exoplanet found in habitable zone

9:55 am

Astronomers using both space- and ground-based telescopes have confirmed the existence of another rocky exoplanet inside the habitable zone of its star.

The star is a red dwarf 137 light years away. The exoplanet, dubbed TOI-175 b, is estimated to be larger than Earth, with a diameter 1.5 times that of our home planet. It orbits its star every nineteen days. Even more intriguing, the data suggests this star has a second exoplanet even better positioned in the habitable zone that would be the smallest habitable-zone exoplanet so far found, about the size of Earth.

The second planet however is not yet confirmed.

This discovery is no longer very unique. In the past few years astronomers have discovered a plethora of Earth-sized exoplanets, many in the habitable zone.

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Japan and India team up for unmanned lunar lander mission

9:42 am

Japan and India are now partnering to put a lander/rover on the Moon in 2025, dubbed LUPEX.

Set tentatively for 2025, LUPEX will be launched on JAXA’s H3 launcher, with a 350-kg rover developed by the Japanese agency. ISRO is developing the lander. The instruments will be on the lander and the rover. Initial feasibility studies and the lander’s configuration have been completed. The rover will sample the soil with a driller and the samples will be analysed using equipment on the rover,

Unlike the previously successful lunar landers from both countries (India’s Chandrayaan-3 and Japan’s SLIM), LUPEX is being designed to survive the 14-day-long lunar night, with a mission that is aiming to last three to six months.

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Have these Martian dunes changed in sixteen years?

1:57 pm

Comparing two MRO images taken 16 years apart
Click here and here for the original images.

Overview map

Cool image time! The two pictures above, both rotated, cropped, reduced, and enhanced to match and to post here, were taken by the high resolution camera on Mars Reconnaissance Orbiter (MRO) sixteen years apart. The first, on the left, was taken on February 23, 2007, while the second, on the right, was taken on November 1, 2023.

What drew me to both images was the label for the second: “Dune Change in Arabia Region Crater.” To find out if this image had revealed any changes in the dunes I went back and found the earliest MRO picture of this location, and sized and enhanced the dunes in both to match.

Do you see any changes? I don’t. However, that really means nothing. These are not the highest resolution versions that MRO obtains, and a very careful comparison of those best images might detect more subtle changes than our eyes can perceive in the versions above. Also, there might be brightness changes that require careful software analysis.

The white dot on the overview map to the right marks the location, in Arabia Terra, the largest transition region on Mars between the northern lowland plains and the southern cratered highlands. The inset shows the half filled crater in which these dunes sit. The grayed area on the floor of the crater marks the entire dune field, extending eastward to the crater rim from this one spot, indicated by the black dot.

It is likely that the dust is blown into this crater and gets trapped there. Whether the dunes move or change is not clear, though if they do the changes are small, even after almost two decades. Instead, the two pictures suggest these dunes have hardened into a form of sandstone, that can be eroded over time by the wind, but only very very slowly.

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Scientists: No obvious ice in the permanently-shadowed interior of Shackleton Crater

10:59 am

Shadowcam-LRO mosaic
Click for original image.

Using the low-light image produced by the American Shadowcam instrument on South Korea’s lunar orbiter Danuri, scientists now belief that there are no thick obvious deposits of water ice in in the permanently-shadowed interior of Shackleton Crater at the Moon’s south pole.

The image to the right combines pictures taken by Lunar Reconnaissance Orbiter (LRO) of the region around Shackleton with pictures produced by Shadowcam of its permanently-shadowed interior. From their paper’s conclusion:

The trailing (right) side of Shackleton’s interior is warmer owing to the secondary illumination asymmetry and floor topography. Illumination at the floor of Shackleton is patchy and possibly indicates a similar patchy (50 m scale) temperature distribution, which could mean a spatially irregular concentration of cold-trapped volatiles at the subsurface or mixed with regolith.

According to our Shackleton crater interior mapping from ShadowCam images, there is no observed evidence of thick ice deposits or surface ice that could be easily recognized by any relative brightness features observed in multiple illumination geometries. However, this analysis did not include the estimation of reflectance, nor did it involve reviewing all of the images of Shackleton in this preliminary study. Our hypothesis, in the context of water frost detections in Shackleton, is that if ice or frost is present in Shackleton’s interior, then the concentrations are either below the threshold that results in an observable signature in ShadowCam images, or might be mixed with the regolith at the detected areas. At other places where surface temperatures are below 110K, water frost could be hidden in subsurface layers.

The paper’s main purpose was to identify the dim lighting sources within the crater, all of which come from light bouncing off other surfaces. In the process the scientists obtained a better understanding of the surface itself.

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China’s Chang’e-7 lunar mission will target the rim of Shackleton Crater

9:15 am

The Moon's south pole, with landers

China’s Chang’e-7 lunar mission, which will include an orbiter, lander, rover, and “mini-flying” probe, will land in 2026 on the rim of Shackleton Crater, one of the same candidate landing zones for NASA’s manned Artemis program.

The map to the right shows the lander’s approximate landing site, on the illuminated rim of thirteen-mile-wide Shackleton Crater at the Moon’s south pole. The candidate landing zone for NASA is also on this rim, but the location might not be precisely the same. From the abstract of the published paper [pdf] outlining the project’s science goals:

The lander will land on Shackleton crater’s illuminated rim near the lunar south pole, along with the rover and mini-flying probe. The relay satellite (named Queqiao-2) will be launched in February 2024 as an independent mission to support relay communication for ongoing scientific exploration of Chang’E-4 (CE-4), the upcoming Chang’E-6 (CE-6) in 2024, and subsequent lunar missions.

Though the abstract states the target is Shackleton’s rim, the paper is less specific, showing a map with a much wider “candidate landing region”. It is unclear if China as yet has the ability to land with the pinpoint accuracy necessary to hit the rim as stated. The paper is also devoid of any technical details about the lander, rover, or its mini-flyer. It lists the science instruments and their science goals, but describes nothing more specific. For example, will the flyer bounce or use small rockets to lift off? Or will it simply be released prior to landing with no capability of taking off again?

The big story here is the race to get to Shackleton first. NASA presently hopes its first Artemis manned mission to land on the Moon, Artemis-3, will arrive in September 2026, with its stated goal landing at or near the south pole. That schedule is certainly tentative, based on NASA’s recent track record. China is now targeting that same year, but its recent track record for its lunar program has been far more reliable.

The Outer Space Treaty forbids both countries from claiming any territory, but possession is always nine-tenths of reality. Expect China to touch down first, and hold what it touches.

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A plateau of friable rock on Mars

2:11 pm

A plateau of friable rock on Mars
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on September 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labels this “Friable Outcrops in Aeolis Dorsa.” What we are looking at is the northeasternmost tip of a 30-mile long plateau that marks the northern edge of Mars southern cratered highlands. For most of its length the top of that plateau is relatively smooth, broken by some vague surface features and a few scattered craters (suggesting it is relatively young). However, as you approach the plateau’s edges and especially that northeastern tip the surface begins to break up into the rough terrain shown to the right. It appears that the prevailing winds from the north are scouring the soft topsoil here and causing it to wear away, leaving behind those innumerable small ridges, almost all of which are oriented from north-to-south.

But why is the topsoil here soft and so easily scoured?
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The dark matter in the Milky Way is not behaving as its supposed to

8:56 am

The uncertainty of science: Scientists using precise data of the motions of the outer stars of the Milky Way from the Gaia orbiting telescope have found they do not rotate the galaxy’s center as fast as expected, based on the theory of the existence of dark matter.

Dark matter was proposed to explain why in other galaxies the speed of rotation of outer stars does not appear to decline with distance (as seen for example with the planets in our solar system) but remains the same, no matter how far out you go. That extra speed suggests there must be unseen matter pulling on the stars.

[N]ew results that combine Gaia measurements with those from APOGEE (Apache Point Observatory Galactic Evolution Experiment), performed on a ground-based telescope in New Mexico, USA, and which measures the physical properties of stars to better judge their distance, have indeed measured the Milky Way’s rotation curve for stars out farther than ever before, to about 100,000 light years. “What we were really surprised to see was that this curve remained flat, flat, flat out to a certain distance, and then it started tanking,” says Lina Necib, who is an assistant professor of physics at MIT, said in a statement. “This means the outer stars are rotating a little slower than expected, which is a very surprising result.”

…The decline in orbital velocity at these distances implies that there is less dark matter in the center of our galaxy than expected. The research team describe the galaxy’s halo of dark matter as having been “cored,” somewhat like an apple. The crew also says there’s not enough gravity from what dark matter there seems to exist there, to reach all the way out to 100,000 light years and keep stars moving at the same velocity.

The rotation data of other galaxies, while somewhat robust, also includes a number of assumptions might be fooling us into thinking that the speeds are higher than expected. The more precise data gathered nearby, in the Milky Way, is now suggesting those assumptions and that distant data must be questioned.

Or to put it more bluntly, dark matter remains an ad hoc solution to a mystery that astronomers really don’t understand, or have sufficient data to explain. It might very well be a wild goose chase that has made them miss the real answer, whatever that might be.

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The internal structure of 19 galaxies, as seen in the infrared by Webb

9:48 am

The internal structure of 19 galaxies, as seen by Webb
Click for original image.

Scientists using the Webb Space Telescope today released false color infrared images of nineteen different spiral galaxies, each showing the complex internal structure that traces of spiral arms, but not always.

A compliation of those infrared images is to the right, reduced and sharpened to post here.

[Webb]’s NIRCam (Near-Infrared Camera) captured millions of stars in these images, which sparkle in blue tones. Some stars are spread throughout the spiral arms, but others are clumped tightly together in star clusters.

The telescope’s MIRI (Mid-Infrared Instrument) data highlights glowing dust, showing us where it exists behind, around, and between stars. It also spotlights stars that have not yet fully formed – they are still encased in the gas and dust that feed their growth, like bright red seeds at the tips of dusty peaks. “These are where we can find the newest, most massive stars in the galaxies,” said Erik Rosolowsky, a professor of physics at the University of Alberta in Edmonton, Canada.

The data suggests, not unexpectedly, that the central parts of each galaxy are older, formed first, with starbirth occurring later in the outer regions. A lot of further analysis however will be required to understand all the patterns exhibited in these images and their larger significance in connection with galaxy formation.

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The future of astronomy, as seen by PBS News in 1991

6:01 pm

An evening pause: Today is the 75th anniversary of the moment astonomers took the lens cap off the Hale Telescope at Palomar, what astronomers call “first light.” In honor of this anniversary, tonight’s evening pause is a somewhat well-done news piece produced by PBS in 1991, describing the state of ground-based astronomy at that time, which was actually another key moment in the history of astronomy. After decades of no advancement following the Hale telescope, the field was about to burst out with a whole new set of telescopes exceeding it significantly, based on new technologies. We today have become accustomed to those new telescopes, but in 1991 they were still incomplete or on the drawing board.

This was also after the launch of Hubble but before it was fixed, so this moment was also a somewhat dark time for astronomy in general. Watching this news piece gives you a sense of history, as seen by those living at that time. It also lets you see some good examples of the standard tropes of reporters as well as some astronomers. They always say this new telescope (whatever and whenever it is) is going to allow us to discover the entire history of the universe, even though it never can, and never will.

Hat tip Mike Nelson.

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Lunar Reconnaissance Orbiter photographs SLIM on the Moon

1:16 pm

LRO images showing before and after SLIM's landing
Click for blink animation.

Scientists using Lunar Reconnaissance Orbiter (LRO) were able on January 24, 2024 to obtain a photograph of the SLIM landing site on the Moon, and produce a before and after blink animation showing the lander on the ground.

The two pictures to the right, before and after, were taken from that animation. The bright speck in the after image is SLIM, sitting upside down on the surface. The faint streak of light material going from right to left lower in the photo comes from the fresh ejecta material thrown out from the nearby 1,425-foot-wide Shioli Crater to the west.

This picture confirms once again that SLIM achieved its main goal, landing precisely within a tiny landing zone only 300 feet across.

The landing occurred in the morning on the Moon, so the Sun was in the east. Because SLIM got flipped upside down just before touchdown, its one solar panel ended up facing west, where no sunlight could touch it. Based on the shadows in this picture, east is to the left, and west to the right. The solar panel is sitting in the shadow on SLIM’s right side.

In about a week the Sun will begin setting to the west, illuminating that panel. Engineers in Japan hope that at that time the panel will begin to recharge the spacecraft’s batteries, and it will then begin to operate again, if only a short while before the Sun sets and the very cold and hostile lunar night begins. There is little expectation of SLIM surviving that long two-week lunar night, even if it gets its batteries fully charged.

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Ingenuity’s final resting site on Mars

1:00 pm

Overview map
Click for interactive map.

Ingenuity's damaged propeller
Click for orignal image.

The photo to the right was downloaded from Ingenuity today, and looks downward at the ground below the helicopter, showing the shadow of one of its propellers, with the damage at its tip indicated by the arrow.

It is this damage that forced NASA management to retire the helicopter yesterday. With the tip of one of Ingenuity’s two propellers damaged, the helicopter simply can no longer fly reliably, or at all.

The green dot on the map above shows Ingenuity’s final resting spot. The blue dot shows Perseverance’s present position. Perseverance will surely at some point approach Ingenuity closely to get better pictures of the damage to help engineers better figure out what happened and why. For example, did the propellor simply break during flight? And if so, why?

I freely admit that my optimistic speculations last week were wrong, that Ingenuity was merely having communications issues with Perseverance. I also suspect the Ingenuity engineers were hoping the same thing, and were far more disappointed than I to discover otherwise.

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Lucy’s upcoming travels leading to its exploration of the Trojan asteroids

10:16 am

Lucy's future route through the solar system
Click for original image.

The Lucy engineering team today issued an update, outlining the spacecraft’s upcoming fly-bys in 2024 that will carry it to its next asteroid rendezvouses, first with an asteroid in the main belt, and then with four Trojan asteroids orbiting in Jupiter’s orbit but 60 degress ahead.

The map to the right shows this route. The solid red/white line indicates Lucy’s travels in 2024.

In late January, Lucy will begin the series of two deep space maneuvers. On January 31, the spacecraft will briefly operate its main engines for the first time in space. After analyzing the spacecraft’s performance during that brief burn, the team will command the spacecraft to carry out a larger maneuver, nominally on February 3. Combined, these two maneuvers are designed to change the velocity of the spacecraft by around 2,000 mph (approximately 900 meters per second) and will consume roughly half of the spacecraft’s onboard fuel.

That first brief burn will not only test the engines, it will also tell engineers whether one of Lucy’s solar panels — still not fully deployed and latched properly — will not be disturbed by it. If not, they will proceed with the second burn.

After this it will zip past the Earth, which will slingshot it out to Jupiter orbit, passing one main belt asteroid along the way.

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Ingenuity’s mission on Mars is over

3:55 pm

Ingenuity takes off!
Ingenuity takes off on its first flight, April 19, 2021.
For full images go here and here.

NASA today announced that Ingenuity’s mission on Mars has now ended due to damage sustained to one of its propellers during its 72nd flight.

While the helicopter remains upright and in communication with ground controllers, imagery of its Jan. 18 flight sent to Earth this week indicates one or more of its rotor blades sustained damage during landing, and it is no longer capable of flight.

Ingenuity’s engineering mission was designed initially to simply prove that air-powered flight in Mars’ thin atmosphere was possible by a test program of four flights over 30 days. It worked so well that it just kept going and going. During its almost three years of operation on Mars, the helicopter completed 72 flights, for a total air time of about 128 minuntes. It flew a total of about eleven miles, reaching a maximum speed of over 22 miles per hour and a top altitude of about 79 feet. On its 69th flight it traveled a record 2,315 feet, almost a half mile.

All future Mars missions have been changed forever by the success of Ingenuity and its designers and engineers. For example, there are already hints of a helicopter mission to Mars’ giant canyon Valles Marineris. In addition, NASA redesigned its Mars Sample Return Mission to include helicopters based on what it learned from Ingenuity.

More important, Ingenuity suggests that when settlers finally colonize the red planet, it is very possible that air travel will start out more important than ground transport. In fact, long distance roads might never be built, for any number of reasons, because air travel will be available from the beginning.

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All climate models continue to be wrong, overstating warming to significant degrees

12:24 pm

Climate models versus data
Click for full resolution graph.

According to a new analysis comparing actual satellite observations of the climate since 1979 with all the climate models used by the IPCC and global warming activitists, it appears that every single climate model continues to overstate significantly their predictions of warming, with that error increasing with time. From the paper’s abstract:

Warming of the global climate system over the past half-century has averaged 43 percent less than that produced by computerized climate models used to promote changes in energy policy. In the United States during summer, the observed warming is much weaker than that produced by all 36 climate models surveyed here.

While the cause of this relatively benign warming could theoretically be entirely due to humanity’s production of carbon dioxide from fossil-fuel burning, this claim cannot be demonstrated through science. At least some of the measured warming could be natural. Contrary to media reports and environmental organizations’ press releases, global warming offers no justification for carbon-based regulation.

The research was done by Roy Spencer of the University of Alabama, who has also been the principal investigator on one climate satellite. The graph to the right, chart 2 of his paper, shows the error of every single climate model, with some models so wrong they are essentially useless to predict anything.

What is significant about this research is not that these models are wrong, it is that they are all wrong in the same direction. If the climate science community was approaching this work honestly with an effort to be unbiased, we should should expect some models to predict too little warming, and others too much. That all predict too much warming suggests that every single one of these models is tainted by politics and confirmation bias. The people who write the models want global warming to occur (almost certainly for political reasons), and so their models always lean in that direction.

What is even more disturbing is that Spencer’s work shows that the difference between the models and observations is growing, as indicated by chart 3 from his paper, below.
» Read more

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