Tag: science

Citizen scientist project discovers 16 active asteroids

10:39 am

A project that has enlisted approximately 8,300 ordinary citizens to review more than 430,000 photos taken by a telescope in Chile has discovered sixteen asteroids that produce comae and tails like comets.

Identifying and tracking active asteroids whose activity specifically appears to be due to the sublimation of ice – known as main-belt comets – is a particular interest of the project team, as it is an essential part of understanding the abundance and distribution of volatile material like ice in the Solar System.

…The project, utilizing publicly available Dark Energy Camera (DECam) data from the Victor M. Blanco telescope in Chile, involved the examination of more than 430,000 images of known minor planets by 8,300 volunteers, where images identified by citizen scientists as being likely to contain active asteroids were then passed on to the science team for confirmation and additional analysis.

You can read the research paper here. If you want to participate, the Active Asteroids project is still on-going, and can be accessed here.

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Cracking terraces in Valles Marineris

3:27 pm

Overview map

Cracking terraces in Valles Marineris
Click for original image.

Inset

Today’s cool image returns us to the truly spectacular terrain found on the floor of West Candor Chasma, one of the giant side canyons that form Valles Marineris, the biggest canyon in the solar system, many times larger than the Grand Canyon on Earth.

The picture to the right, cropped, reduced, and sharpened to post here, was taken on January 5, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). On the overview map above its location is indicated by the red dot in the inset. The two green dots mark previous cool images from August 2022 and February 2024.

All three images show the same wild alternating dark and light terracing, suggesting many sedimentary layers like those seen in our Grand Canyon, but enhanced by the different erosion processes of the thin Martian atmosphere and its one-third Earth gravity.

The second image to the right zooms in on the area indicated by the rectangle. What makes this area doubly interesting are the cracks that appear to cut through the terraces. In the north-south crack it also appears that the terraces are now offset on each side of the crack.

Apparently, some event, likely an earthquake that occurred after the terraces formed, caused the ground to rip apart, with the earth shifting sideways on either side. Though the seismometer on the InSight lander detected no major quakes in this region, this image suggests they have occurred here, sometime in the past.

To give you a sense of scale, the canyon’s nearby rim to the west is about 14,000 higher, making that canyon wall two to three times taller than the walls of the Grand Canyon.

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A relatively dim star is expected to become one of the brightest in the sky later this year

9:49 am

As it has done twice before at intervals of 80 years, a relatively dim star is expected to go nova later this year, becoming for a short time one of the brightest stars in the sky.

Located in the Northern Crown constellation, T Coronae Borealis (T CrB) is a pretty average looking star, most of the time. With a brightness of about magnitude +10, it’s right on the limits of what you could see with a pair of binoculars, and even if you do go looking there’s not much to see.

At least, that’s the case for about 79 out of 80 years. But on that 80th year, the star suddenly brightens drastically up to around magnitude +2, which puts it on par with the north star Polaris. That makes it one of the brightest stars in the night sky, easily visible with the naked eye even when washed out by city lights. This once-in-a-lifetime outburst last occurred in 1946, and before that 1866.

And lucky for stargazers, T CrB seems to be about two years ahead of schedule, with astronomers predicting it will flare up again between March and September 2024. It’ll appear as a bright ‘new’ star for a few days with the naked eye, and a little over a week with binoculars, before it settles down again for another few decades. Astronomers noticed last year that T CrB had started to dim, which data from 1945 showed preceded the last brightening event.

The star is actually a binary, made up of a white dwarf and a red giant. The white dwarf is pulling material from the red giant, and as that new material piles up, it eventually gathers enough mass to go critical and produce a thermonuclear explosion. The result is a nova, a smaller version of a supernova that unlike supernovae occurs repeatedly.

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ESA: Euclid vision cleared after being fogged by ground ice, after launch

9:13 am

The European Space Agency (ESA) today announced that engineers have successfully “de-iced” the optics of its new Euclid space telescope that developed after it was launched in July 2023.

It was always expected that water could gradually build up and contaminate Euclid’s vision, as it is very difficult to build and launch a spacecraft from Earth without some of the water in our planet’s atmosphere creeping into it. For this reason, there was an ‘outgassing campaign’ shortly after launch where the telescope was warmed up by onboard heaters and also partially exposed to the Sun, sublimating most of the water molecules present at launch on or very near Euclid’s surfaces. A considerable fraction, however, has survived, by being absorbed in the multi-layer insulation, and is now being slowly released in the vacuum of space.

After a huge amount of research – including lab studies into how minuscule layers of ice on mirror surfaces scatter and reflect light – and months of calibrations in space, the team determined that several layers of water molecules are likely frozen onto mirrors in Euclid’s optics. Likely just a few to few tens of nanometres thick – equivalent to the width of a strand of DNA – it’s a remarkable testament to the mission’s sensitivity that it is detecting such tiny amounts of ice.

While Euclid’s observations and science continue, teams have come up with a plan to understand where the ice is in the optical system and mitigate its impact now and in the future, if it continues to accumulate.

It appears this new process has worked, according to a short update at the link.

Normally spacecraft are vented both on the ground during thermal testing, as well as when they reach orbit. It appears some of these normal procedures were either insufficient for Euclid’s needs, or threatened its optics if done as usual. This press release suggests that Euclid required very targeted venting processes that would not harm its sensitive optics, and that the procedures have worked.

I must admit I am suspicious of these claims. During development and after launch Euclid has had a number of problems. First, back in 2017 the NASA instrument on the telescope had to be completely rebuilt when it was found to be defective. Second, after launch engineers discovered unexpected light leaks on the mirror that now limit where it can look. Third, the telescope required a software patch to fix its pointing system, which was confusing cosmic rays for guide stars, causing it to shift positions randomly.

I can’t help wondering if this icing on the mirrors was also due, not to actual planning as suggested by ESA’s press release, but to poor ground testing and engineering that missed what is a common problem on spacecraft and thus required a post-launch improvised fix. I admit I might be wrong, but I still wonder.

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China launches communications orbiter towards the Moon

8:19 pm

Using its Long March 8 rocket lifting off from its coastal Wenchang spaceport, China today launched its second Quequiao communications satellite to the Moon, designed to relay data from its landers on the far side back to Earth.

The Queqiao 2, or Magpie Bridge 2, satellite was lifted atop a Long March 8 carrier rocket that blasted off at 8:31 am from a coastal launch pad at the Wenchang Space Launch Center in China’s southernmost island province of Hainan.

After a 24-minute flight, the satellite was released from the rocket and then entered into a lunar transfer trajectory. At the same time, the solar wings and communication antennas smoothly unfolded.

This satellite is in preparation for the May launch of China’s Chang’e-6 lunar mission to grab samples from the Moon’s far side and bring them back to Earth. In the meantime it will test its capabilities by relaying data from the Chang’e-4 lander and its Yutu-2 rover, still in operation on the far side after landing there in January 2018.

The leaders in the 2024 launch race:

27 SpaceX
11 China
3 Russia
3 Rocket Lab

American private enterprise still leads the rest of the world combined in successful launches 31 to 20, while SpaceX leads the entire world, including American companies, 27 to 24.

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Gehrels Swift space telescope now in safe mode

9:33 am

The Gehrels Swift space telescope, used to get real time observations of gamma ray bursts and other high energy deep space events, is presently in safe mode due to the failure of one of its three gyroscopes.

On March 15, NASA’s Neil Gehrels Swift Observatory entered into safe mode, temporarily suspending science operations due to degrading performance from one of its three gyroscopes (gyros), which are used to point the observatory for making observations. The rest of the spacecraft remains in good health.

Swift is designed to successfully operate without one of its gyros if necessary; however, a software update is required. The team is working on the flight software update that would permit the spacecraft to continue science operations using its two remaining gyros.

The telescope has been operating in orbit for nearly twenty years, far longer than originally planned. Its observations were crucial in discovering that gamma ray bursts occur at vast distances and involve either the core collapse of a star or the merger of two neutron stars.

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India’s Vikram lander disturbed the lunar surface the least of all landers

9:29 am

According to an analysis of images taking before and after landing, engineers have concluded that India’s Vikram lander disturbed the lunar surface the least of all landers, due to its use of multiple smaller landing engines.

Presenting the new findings at LPSC on Monday, [ISRO scientist Suresh K] attributed the intriguingly short dust plume to the lack of a central engine on the spacecraft, which resulted in a lower engine thrust during descent. Starting its “rough braking phase” at an orbit of 18.6 miles (30 kilometers) above the lunar surface, when the spacecraft reached 0.4 miles (0.8 kilometers) above its targeted landing area, it switched off two of its four 800-newton engines such that two diagonal engines remained operational all the way until touchdown. The mission used the “least powerful engine till date,” [Suresh] K said. “We’ve observed very less disturbance on the surface.”

You can read their paper here [pdf].

Finding ways to reduce the dust kicked up during landings will be critical for the early missions to the Moon, before landing pads can be constructed. This research suggests that when Starship lands, it should use only its outer engines, and gimbal them sideways, in order to reduce the dust thrown up around it.

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Scientists: DART impact of Dimorphos changed its orbit and reshaped the asteroid

9:18 am

Dimorphos shape change
Click for original graphic.

According to a new study, the DART impact of Dimorphos in September 2022 not only shortened its orbit around the larger asteroid Didymos, it reshaped the asteroid itself, warping its widest point sideways from its equator.

You can read the paper here.

More important, the scientists found that the changes evolved over time.

Over the following weeks, the asteroid’s orbital period continued to shorten as Dimorphos lost more rocky material to space, finally settling at 11 hours, 22 minutes, and 3 seconds per orbit – 33 minutes and 15 seconds less time than before impact. This calculation is accurate to within 1 ½ seconds, Naidu said. Dimorphos now has a mean orbital distance from Didymos of about 3,780 feet (1,152 meters) – about 120 feet (37 meters) closer than before impact.

Similarly, the reshaping of the asteroid into its present shape took time. As the scientists noted in their conclusion, “it takes time for a binary system to settle after a kinetic impact event.”

Because of Dimorphus’s rubble pile nature, its shape and orbit should continue to evolve over the coming decades, as more of the ejecta from the impact slowly falls back onto its surface and the asteroid surface adjusts over time. This in turn should also effect the orbit, though by only very tiny amounts.

I continue to wonder if the entire solar orbit of this asteroid binary system was impacted at all by these changes. Any changes would likely be tiny, but it is important to know to see if such an impact can actually do such a thing. To find out will take several more years, as ground telescopes continue to track the asteroid.

In October 2024 the European probe Hera will launch on a mission to this asteroid binary, with its arrival expected in December 2026. At that time we will get a much better look at both asteroids and how the impact affected them.

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The vast Martian plains of lava

3:49 pm

The vast Martian lava fields
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on January 31, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled “Lava Embaying Highlands Ridge”, it shows an alcove along a ridgeline that appears filled with material, in this case solid lava.

If you look closely at the ridgeline, you can see several dark streaks on its southern slopes. These streaks could be one of two unique Martian features that remain unexplained. They could be slope streaks, which occur randomly through the year and fade with time, or recurring slope lineae, which occur seasonally at the same locations. In either case, though the streaks look like avalanches, they don’t change the topography, have no debris piles at their base, and even sometimes flow uphill for short lengths. Though there are a number of theories for their formation, many involving dust, none has been accepted as confirmed.

This location and its lava however are the stars of this picture, for a number of reasons, all revealed by the overview map below.
» Read more

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Mapping the layered geology of Mars

12:16 pm

Mapping the layers on Mars
Click for original image.

Today’s cool image is an update of a previous cool image from July 2021. Then, I posted a captioned high resolution Mars Reconnaissance Orbiter (MRO) photo of the many terraced layers within a 13-mile-wide crater dubbed Jiji and located in Arabia Terra, the largest transition zone between the Red Planet’s northern lowland plains and the southern cratered highlands. At that time the caption noted that research was on-going to see if the same layers could be identified in two other nearby craters, Banes and Sera, and thus use that data to extrapolate the long term geological history of this region on Mars.

Today’s cool image to the right, rotated, cropped, reduced, and enhanced to post here, was taken on January 4, 2024 as part of this research, and shows the layers in 18-mile-wide Sera crater, located only about ten miles to the east of Jiji crater. The highest mesa near the bottom of the picture is about twenty feet high on its southern side, but about 140 feet high to the north. The difference is because the crater floor under the mesa is sloping downward to its lowest point to the north.
» Read more

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Betelgeuse dimming again

10:00 am

Betelqeuse
An optical image of Betelgeuse taken in 2017 by a ground-based
telescope, showing its not unusual aspherical shape.
Click for original image.

It appears that the red giant star Betelgeuse is once again dimming, as it did in 2019-2020.

Betelgeuse, located in Orion’s right shoulder, ordinarily shines at magnitude +0.4, a close match to neighboring Procyon in Canis Minor. But since late January it’s lost some of its luster — at least a third of a magnitude’s worth. That may not sound like much especially given the star’s variable nature, but the red supergiant star is currently the faintest it’s been in the past two years.

Betelgeuse is less like a stable star and more like a gasbag in weightlessness, its shape bouncing in and out as convection bubbles from within push their way to the surface. In some cases, as in 2019-2020, a burst of a bubble releases dust and material, which scientists believe acted to block the star’s light at that time. The dimming now could be for the same reason. Or it could be because the star’s brightness is fundamentally variable. For years it reliably pulsed every 400 days, though that variation pattern now seems to have vanished since 2020.

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Engineers report progress in restoring proper communications with Voyager-1

9:51 am

According to a NASA update yesterday, software engineers for the Voyager-1 spacecraft now beyond the edge of the solar system have managed to decipher the garbled data the spacecraft’s computers have been sending back to Earth since November 2023, and are in the process of analyzing that data with the hope of restoring full understandable communications.

The source of the issue appears to be with one of three onboard computers, the flight data subsystem (FDS), which is responsible for packaging the science and engineering data before it’s sent to Earth by the telemetry modulation unit.

On March 3, the Voyager mission team saw activity from one section of the FDS that differed from the rest of the computer’s unreadable data stream. The new signal was still not in the format used by Voyager 1 when the FDS is working properly, so the team wasn’t initially sure what to make of it. But an engineer with the agency’s Deep Space Network, which operates the radio antennas that communicate with both Voyagers and other spacecraft traveling to the Moon and beyond, was able to decode the new signal and found that it contains a readout of the entire FDS memory.

This new readable data was the result of a command sent two days before, suggesting that engineers are on the right track. Because Voyager-1 is so far away, 15 billion miles, it takes 22.5 hours for any command to be sent to the spacecraft, and another 22.5 hours for ground controllers to get a response. This long lag time has slowed the effort to fix the problem, but this new success suggests that a full recovery is possible.

That recovery is going to be relatively short-lived, no matter what. The nuclear-powered power sources for both Voyager spacecraft, flying since 1977, are expected to finally run out of power sometime in 2026, after almost a half century of operation. Moreover, the computers on both Voyagers are the longest continuously running computers in history.

The engineering achievement of both is astonishing.

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Scientists: Mars’ mysterious slope streaks and seasonal recurring lineae are caused by dust

1:08 pm

Massive flow on Mars
A typical Martian slope streak.

On Mars there are two mysterious features that are somewhat similar but entirely unique to the Red Planet, and for years have baffled planetary geologists as to their origins.

One feature is called slope streaks, which appear randomly year-round as either dark or bright streaks on slopes. They resemble avalanches, except that they do not change the topography, have no debris piles at their base, and sometimes travel along that topography, sometimes even going uphill for short distances. Over time these streaks then fade.

The other feature is called recurring slope lineae, because though they look like slope streaks, they are not random but appear seasonally at the same places each year. Lineae are also always dark.

Scientists have proposed many theories to explain both, with most theories involving some form of water process, either the seepage of brine from below or water vapor causing the Martian surface dust to flow, like droplets on a car windshield. None of these theories has been confirmed, or entirely accepted.

Two studies at this week’s 55th annual Lunar and Planetary Science Conference in Texas have both concluded that water is not a factor in the formation of either phenomenon. Instead, both papers propose a much simpler explanation: Wind and blowing dust interact to cause small dust avalanches.
» Read more

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Lucy’s first encounter with an asteroid produced surprises

12:39 pm

Dinkinesh, with Salam

At the 55th annual Lunar and Planetary Science Conference presently being held in Texas, the science team for the Lucy asteroid mission presented their first papers outlining what they learned during the spacecraft’s first asteroid encounter, flying past the main belt asteroid Dinkinesh on November 1, 2023.

To the right is the the best image taken at closest approach, at about 270 miles distance, annotated to include the analysis of Dinkinesh’s shape by scientists. As noted in the summary paper [pdf], the asteroid is about a half mile in diameter, and appears to have an equatorial ridge, similar to the ridges found on the near-Earth rubble-pile asteroids Bennu or Ryugu. Dinkinesh is not a rubble pile, however. Though boulder-strewn, it appears more solid, and even has what the scientists call a longitudinal trough, as indicated in the picture.

The ridge overlays the trough implying that it is the younger of the two structures. However, there is as yet no information to better constrain their relative ages, and thus they could potentially have formed in the same event. Indeed, Dinkinesh’s ridge and trough are likely the result of mass failure and the reaccretion of material, and may both be linked to the formation of Selam.

That flyby had produced one major surprise, the existence of a smaller satellite asteroid orbiting Dinkinesh, now dubbed Selam. It is shown in the lower left, as it appeared from behind the main asteroid as Lucy flew past. A later picture however revealed an even greater surprise.
» Read more

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There likely is little or no ice in the Moon’s permanently shadowed craters

11:47 am

Shadowcam-LRO mosaic
The floor of Shackleton Crater showing no obvious ice deposits,
as seen by Shadowcam. The black cross marks the south pole.
Click for original image.

This week the 55th annual Lunar and Planetary Science Conference is being held in Texas. The conference was originally established in connection with the Apollo missions to allow scientists to release their Moon research results. It quickly morphed into an annual event covering research from the entire planetary research community.

I have reviewed the abstracts for this year’s meeting, and culled what I think are the most significant new results from the conference, which I will report on in the next few posts.

We begin however with possibly the most important result from the conference, given by the science team for the ShadowCam instrument on South Korea’s Danuri lunar orbiter. That low-light camera was designed to take high resolution pictures of the permanently-shadowed craters of the Moon, to see if there was any visible or obvious ice hidden there. Though the science team presented a number of papers, the summary paper [pdf] by the instrument’s principal investigator, Mark Robinson of Arizona State University, gave the bottom line:

The data so far is finding very little evidence of water ice in these dark regions.
» Read more

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A Martian tadpole

3:01 pm

Overview map

A Martian tadpole
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on December 28, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The white dot on the overview map above marks the location, with the rectangle in the inset marking the area covered by the picture. The science team labels this “inverted features,” a more vague way to describe the feature geologists dub “inverted channels.” The flow of a river or glacier acts to harden and increase the density of the channel bed. Later, the water or ice disappears, leaving just the canyon.

Even later, erosion begins to wear away the surrounding terrain. Because the canyon floor is now harder than that surrounding terrain, that floor is more resistent to erosion, and eventually becomes ridge following the exact same path as the long gone river or glacier.

This is what we have here, with this inverted channel, which is about five miles long, once draining into the deeper eroded valley to the south.

The location is at 38 degrees north latitude and inside the 2,000-mile-long mid-latitude region I dub glacier country, because almost every image shows evidence of glaciers or ice flows on the surface. This picture however is a rare exception. The features in this picture instead appear to be bedrock, something that is rarely seen in the canyons and craters in glacier country. It is beyond my pay grade however to explain why this spot lacks such features. Or it could be the near surface ice here looks so much like bedrock I am misinterpreting the picture.

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Sunspot update: The Sun continues what appears will be a weak maximum

10:30 am

As I have done each month since 2011, I am now posting an annotated version of NOAA’s monthly graph, tracking the solar sunspot activity on the Earth-facing hemisphere of the Sun. The NOAA updated graph was posted at the start of March, covering activity through the end of February, so this report is a little later than normal.

That graph is below. In February sunspot activity remained essentially steady, only slightly higher than the activity from the month before. Those numbers also hovered at about the same level seen since August 2023.
» Read more

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The strange surface of the perennial dry ice cap at Mars’ south pole

4:40 pm

The strange surface of Mars' dry ice cap
Click for original image.

Cool image time! The picture to the right, cropped to post here, was taken on January 24, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a region about 180 miles from the south pole of Mars.

This terrain is intriguing because is the pattern of ridges that cover it entirely. I have simply cropped the original image to show these ridges in highest resolution. The full image shows them covering a region much larger than this.

What are we looking at? Because it is near the pole, it is likely that the black splotches are caused by carbon dioxide gas breaking through the winter mantle of dry ice that covers the poles during the winter months and then sublimates away, from the bottom, each spring. As the dry ice turns to CO2 gas that gas is trapped, until it can find a weak spot in the overlying mantle. When the pressure builds enough, the mantle breaks, the gas escapes, and as it does so it deposits the dark dust around the breakage. That dust fades as the mantle disappears.

Sounds good, eh? Not so fast.
» Read more

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Hubble and Webb confirm decade-long conflict in universe’s expansion rate

8:58 am

The uncertainty of science: New data from both the Hubble and Webb space telescopes has confirmed Hubble’s previous measurement of the rate of the Hubble constant, the rate in which the universe is expanding. The problem is that these numbers still differ significantly from the expansion rate determined by the observations of the cosmic microwave background by the Planck space telescope.

Hubble and Webb come up with a rate of expansion 73 km/s/Mpc, while Planck found an expansion rate of 67 km/s/Mpc. Though this difference appears small, the scientists in both groups claim their margin of error is much smaller than that difference, which means both can’t be right.

You can read the paper for these new results here.

The bottom line mystery remains: The data is clearly telling us one of two things: 1) the many assumptions that go into these numbers might be incorrect, explaining the difference, or 2) there is something fundamentally wrong about the Big Bang theory that cosmologists have been promoting for more than a half century as the only explanation for the formation of the universe.

The solution could also be a combination of both. Our data and our theories are wrong.

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The really really strange landscape of Cydonia on Mars

12:21 pm

Some really strange terrain on Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on January 3, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows what the camera team describes merely as “landforms.”

In truth, these features, as well as almost everything in the surrounding terrain beyond the edge of this picture, are possibly the weirdest geological features on Mars. The two mounds, no more than fifteen feet high at the most, resemble pimples. The rough ground to the north actually appears to be some flow that worked its way around the mounds, as indicated by the arrows. The crack to the southeast of the two mounds appears to be an extension of a fault line that cuts through the center of the larger mound, suggesting the mound is some form of eruption belching out of that fissure.

That the latitude is 42 degrees north, these weird features all suggest some form of ice-based volcanic activity, because the ground here is probably impregnated with ice.

As for the bridge connecting the two mounds, who knows what caused it?
» Read more

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Is this really a spiral galaxy?

10:16 am

Is this really a spiral galaxy?

The uncertainty of science: The picture to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope and released on March 4, 2024 by the PR department of the European Space Agency (ESA) as part of its Hubble Picture of the Week program. It shows what the press release claims is a spiral galaxy about 55 million light years away, seen edge on.

In this image NGC 4423 appears to have quite an irregular, tubular form, so it might be surprising to find out that it is in fact a spiral galaxy. Knowing this, we can make out the denser central bulge of the galaxy, and the less crowded surrounding disc (the part that comprises the spiral arms).

If NGC 4423 were viewed face-on it would resemble the shape that we most associate with spiral galaxies: the spectacular curving arms sweeping out from a bright centre, interspersed with dimmer, darker, less populated regions. But when observing the skies we are constrained by the relative alignments between Earth and the objects that we are observing: we cannot simply reposition Earth so that we can get a better face-on view of NGC 4423!

This picture provides a great example of the amount of assumptions that are often contained in astronomical observations. Though the data strongly suggests this is spiral, we must remember this is merely an educated guess, based on that central bulge and the dust lanes visible along the galaxy’s profile. There is actually no guarantee that this is so. As the press release also notes, astronomers are constrained by our viewpoint, and cannot change that viewpoint to get a better view to confirm this guess. For all we know, a face on veiw of this flat galaxy would reveal it has no spiral arms, but instead is mottled and chaotic, a rare type that does exist.

Astronomers do the best they can, but it is important that they (and we) always recognize the limitations.

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Another helicopter mission under development for Mars?

3:17 pm

Another helicopter mission for Mars?
Click for original image.

Today’s cool image to the right, cropped to post here, is probably on its own one of the more boring cool images I have posted over the years, a generally featureless plain with some ripple dunes within a few low hollows.

What makes this picture cool however is the label for the image: “Sample Landing and Traverse Hazards at Possible Helicopter Landing Site.” The picture was taken on January 23, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), with the obvious goal of seeing whether this location can serve as a landing site for a helicopter mission to Mars.

The site is relatively uninteresting because the first goal is to find a safe place to land, but to do so near a location where there is rough geology which only a helicopter can explore. And it appears, from the overview map below, that is exactly what this location is.
» Read more

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Scientists: Europa produces oxygen on its surface, but less than expected

10:18 am

Graphic of Europa
Click for original image.

The uncertainty of science: Scientists using data from a 2022 flyby of the Jupiter moon Europa by the orbiter Juno have determined that the moon produces about 1,000 tons of oxygen every 24 hours on its surface, a large amount but less than most predictions based on previous indirect observations.

The paper’s authors estimate the amount of oxygen produced to be around 26 pounds every second (12 kilograms per second). Previous estimates range from a few pounds to over 2,000 pounds per second (over 1,000 kilograms per second). Scientists believe that some of the oxygen produced in this manner could work its way into the moon’s subsurface ocean as a possible source of metabolic energy.

You can read the paper here. The graphic shows the basic process, as presently theorized. What remains unknown is how or even if that oxygen is transported downward to the theorized underground ocean of liquid water. That the amount created is on the very low end of previous estimates suggests that there will be less free oxygen to support life in that ocean than expected.

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SLIM put back to sleep for second lunar night

3:51 pm

Engineers at Japan’s space agency JAXA have put their SLIM lunar lander back to sleep on February 29, 2024 with the hope it might survive its second night on Moon.

“Although the probability of failure will increase due to repeated severe temperature cycles, SLIM plans to try operation again the next time the sun shines (in late March),” the update from JAXA read, automatically translated from Japanese to English by Google.

Like Intuitive Machines Odysseus lunar lander, SLIM’s overall mission was a success, as it proved it could land automatically within a very small target zone and do so softly enough that it could send back data to Earth. The failures and problems experienced by SLIM, such as having a nozzle fall off causing it land sideways are simply fixes that can be instituted on future missions.

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Ingenuity’s final resting place on Mars

9:27 am

Panorama showing Ingenuity in Jezero Crater
Click for original image.

Overview map
Click for interactive map.

Time for one last cool image of Ingenuity. The picture above, cropped, reduced, and annotated to post here, was created from a mosaic of 67 images taken on February 21, 2024 by the high resolution camera on the Mars rover Perseverance. The white rectangle marks the approximate area covered by the image below, a mosaic of seven pictures taken on February 24, 2024 by Perseverance’s Remote Microscopic Imager camera, normally used to take very close images of nearby rocks but repurposed here to provide a close up of Ingenuity about 1,365 feet away, inside Neretva Vallis. Ingenuity is on the right, and the speck on the left is the section of the rotor blade that broke off and was apparently flung about 49 feet away.

On the overview map to the right, the blue dot marks Perseverance’s position, the green dot Ingenuity’s, and the yellow lines mark the approximate area covered by the panorama above. The red dotted line is Perseverance’s planned route in the coming months.

Close-up of Ingenuity and broken rotor blade
Click for original image.

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Astronomers discover new moons around Neptune and Uranus

8:50 am

Using a observations over several years from a number of ground-based telescopes, astronomers have now identified two new moons around Neptune and one new moon circling Uranus.

The new Uranian member brings the ice giant planet’s total moon count to 28. At only 8 kilometers, it is probably the smallest of Uranus’ moons. It takes 680 days to orbit the planet. Provisionally named S/2023 U1, the new moon will eventually be named after a character from a Shakespeare play, in keeping with the naming conventions for outer Uranian satellites.

…The brighter Neptune moon now has a provisional designation S/2002 N5, is about 23 kilometers in size, and takes almost 9 years to orbit the ice giant. The fainter Neptune moon has a provisional designation S/2021 N1 and is about 14 kilometers with an orbit of almost 27 years. They will both receive permanent names based on the 50 Nereid sea goddesses in Greek mythology.

The two new Neptune moons raises its moon total now to sixteen. The orbits of all three are tilted and eccentric and far from the planets, strongly suggested they are capture asteroids, not objects formed at the same time as the planet.

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A Martian cliff of ash, flushed by wind

1:13 pm

A Martian cliff of ash flushed by wind
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on December 27, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Described merely as an “exposed scarp” by the science team, this cliff edge is actually much more.

First some basic details. The elevation drop from the plateau down to the base of this cliff is about a thousand feet. The material that forms this plateau, scarp, and its base is all volcanic ash. The thicker sections of ash has caused its lower levels to compress, harden into a kind of sandstone. Near the surface however it is more friable, and like sandstone can break apart somewhat more easily.

The prevailing winds at this site are generally blowing to the south, but beginning to turn to the east, which explains the northwest to southeast orientation of the features.

The best analogy I can come up with to explain the erosion of this scarp is as follows: Imagine a deposit of dry mud a few inches thick on pavement. Take a leaf blower and blow at it hard, always in one direction. Eventually the outer edge will break up and blow away, leaving a sharp edge, that will also retreat with time as the wind continues to blow.

Here the winds are eroding that cliff, causing periodic avalanches which dissolve into sand that then blows away, leaving no debris pile at the base of the cliff. The ridges indicate harder material, that breaks away last, which is why there are some ridgelines extending outward from the scarp in line with these ridges. At the same time, these ridges of harder ash still break up with time, as some are cut off suddenly at the cliff edge.
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Final images from Odysseus, lying on its side

9:23 am

One of three pictures downloaded after landing
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In a press conference yesterday, NASA and the private company Intuitive Machines released three pictures taken by the Odysseus lunar lander after it came down a bit too fast, skidded on the ground so that one leg broke, and then tilted over.

The first images from the lunar surface are now available and showcase the orientation of the lander along with a view of the South Pole region on the Moon. Intuitive Machines believes the two actions captured in one of their images enabled Odysseus to gently lean into the lunar surface, preserving the ability to return scientific data.

The best picture, reduced and annotated to post here, is to the right. The spacecraft is tilted about 30 degrees from the vertical. Another picture showed the broken leg on the lander’s other side. The “two actions” mentioned in the NASA quote above refer to the issues that caused the broken leg: the limited ground data the lander used to land, and its larger than expected lateral speed.

The spacecraft is expected to be shut down by today because of lack of power and the advent of the long lunar night. Company officials remain hopeful it will come back to life when the sun rises in several weeks.

Officials from both NASA and Intuitive Machines have correctly noted that this was an engineering test mission, so even these failures make it a success in that the company can use them to improve the next lander. Nonetheless, it would have been nice if things had worked better on this first flight, especially because the problem that led to all the breakdowns, the failure to turn the lander’s range finding system back on after installation on the rocket, was an incredibly stupid human error that should not have happened at all.

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National Science Foundation decides to fund only one giant telescope

8:56 am

The National Science Foundation (NSF) has decided that its astronomy program does not have sufficient funds for building both the Thirty Meter Telescope (TMT) in Hawaii and the Giant Magellan Telescope (GMT) in Chile, and will decide in May which one it will choose.

The GMT and TMT—both backed by consortia of universities, philanthropic foundations, and international partners—set out to build their next generation instruments in the early 2000s. But this privately funded approach, which during the 20th century produced the twin 10-meter Keck telescopes in Hawaii and the two 6.5-meter Magellan telescopes in Chile, stumbled when it came to multibillion-dollar projects. Although design work and mirror casting forged ahead, both projects failed to amass enough funding to complete construction. (A dispute with Native Hawaiians over the Hawaii site has also slowed the TMT.)

I predict that this decision puts the final nail in TMT’s coffin. That telescope was on schedule in 2015 — when construction was set to begin — to be already operational now, well ahead of GMT. The opposition in Hawaii by a minority of leftist protestors, who also had the backing of the state government (run entirely by the Democratic Party), blocked that construction even as the building of GMT’s mirrors proceeded.

Almost a decade later, while TMT sits in limbo, unbuilt, GMT is nearing completion, with its last mirror presently being fabricated and construction at its site now more than half done. It is expected to be finished by 2028, and is almost certainly going to get that NSF funding.

As I noted however in July 2023,

Not that any of this really matters. In the near term, ground-based astronomy on Earth is going to become increasingly impractical and insufficient, first because of the difficulties of making good observations though the atmosphere and the tens of thousands of satellites expected in the coming decades, and second because new space-based astronomy is going to make it all obsolete. All it will take will be to launch one 8-meter telescope on Starship and [GMT] will become the equivalent of a buggy whip.

The great tragedy of TMT is that the astronomers themselves at the project were not willing to fight that tiny minority of protesters, whose protests were based on the essentials of critical race theory that makes whites the devils and all other minorities saints. As academics trained in these insane ideas, the astronomy community accepted this bigoted premise, and out of guilt allowed those protesters to rule.

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Inspector General: Mars Sample Return mission in big trouble

4:25 pm

The present plan for Mars Sample Return

Though the audit published today [pdf] by NASA’s inspector general of the NASA/ESA Mars Sample Return mission partnership tries to couch its language positively, the conclusion one reaches by reading the report is that the project is a mess and will almost certainly not fly when scheduled in 2029, and might even get delayed so much that the Perseverance rover on Mars — an essential component of the mission plan — might no longer be operational at that time.

First the budget wildly out of control.

The trajectory of the MSR Program’s life-cycle cost estimate, which has grown from $2.5 to $3 billion in July 2020, to $6.2 billion at KDP-B in September 2022, to an unofficial estimate of $7.4 billion as of June 2023 raises questions about the affordability of the Program.

In addition, the audit noted that this is not the end, and that based on another independent review the budget could balloon to $8 to $11 billion before all is said and done. (I will predict that as presently designed, that budget will likely reach $15 billion.)
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