Tag: science

Due to thruster problem, the Mercury orbiter BepiColombo will arrive at Mercury almost one year late

9:05 am

The joint ESA and JAXA Mercury mission BepiColombo will now reach its destination eleven months late because its ion electric thrusters are producing less thrust than expected.

The spacecraft is actually made up of two orbiters, one built by the European Space Agency (ESA) and the second built by Japan’s space agency JAXA. During launch and the journey to Mercury each is attached to a third spacecraft called the Mercury Transfer Module (MTM), which has the large electric ion thrusters used for making the mid-course corrections prior to and after each fly-by of the Earth (once), Venus (twice), and Mercury (six) before finally entering orbit around Mercury. It has already completed the Earth, Venus and three Mercury fly-bys.

In April 2024 engineers discovered that during a mid-course correction on April 26st the MTM’s thrusters failed to produce the desired thrust.

Engineers identified unexpected electric currents between MTM’s solar array and the unit responsible for extracting power and distributing it to the rest of the spacecraft. Onboard data imply that this is resulting in less power available for electric propulsion. ESA’s BepiColombo Mission Manager, Santa Martinez explains: “Following months of investigations, we have concluded that MTM’s electric thrusters will remain operating below the minimum thrust required for an insertion into orbit around Mercury in December 2025.”

In order not to lose the mission entirely, the science team has come up with a new trajectory that will have it fly past Mercury on its fourth fly-by on September 4, 2024 only 103 miles above the surface, 22 miles closer than originally planned. This will give it a larger slingshot speed boost to help make up for the under-powered thrusters. It will then make its planned fifth and sixth Mercury fly-bys in December ’24 and January ’25, the adjusted route having it arrive in Mercury orbit eleven months later than planned, in November 2026.

This new plan however means that the pictures taken this week during the Mercury fly-by will provide some nice high resolution details, far better than those produced by the earlier fly-bys.

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A cliff of ice on Mars

12:56 pm

A cliff of ice on Mars
Click for original image.

Cool image time! The picture to the right, cropped to post here, was taken on April 10, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the southern nose of a large plateau located in the deep south of Mars, at 63 degrees south latitude. This cliff is only about 20-25 feet high, but within that small distance orbital imagery as revealed what appears to be an underground layer of ice. When this photo was released in late June, it came with a short caption, which noted:

On these steep scarps, ice can still be seen on the south facing walls of the scarp towards the end of the Southern Hemisphere’s winter.

Note the white sections on that cliff wall, both inside and outside the color strip. The surrounding orange suggests dust and sand. This photo suggests that during the dark winter underground ice leaches out on these slopes, and is then sublimated away when the Sun returns in the spring. Since the south-facing walls remain in shadow the longest, the ice there lasts the longest, leaving behind these patches we see now.

It is also possible that this is not water ice and there is no underground ice layer. Instead, this might be the last leftover of the dry ice mantle that falls as snow and covers all of the Martian high latitudes during the winter, and then sublimates away come spring.
» Read more

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First New Glenn launch, set for October 13, 2024, only has an 8-day launch window

9:16 am

According to an article from Aviation Week today, in order for Blue Origin’s New Glenn rocket to get its payload of two Mars orbiters on their way to Mars it must launch within a very short window lasting only eight days, beginning on the present launch date of October 13, 2024.

The Oct. 13-21 launch window is an ambitious goal. The aft and mid modules of New Glenn’s reusable first stage were recently attached, clearing the path for installation of the vehicle’s seven methane-fueled BE-4 engines, CEO Dave Limp noted in an Aug. 23 update on the X social media site.

A static hot-fire at New Glenn’s Florida launch complex is planned prior to launch. The company did not release the status of the New Glenn upper stage, which is to be powered by a pair of BE-3U engines fueled by liquid oxygen and liquid hydrogen. A hot-fire of the second stage is also pending.

This launch will be the first ever for New Glenn. To get ready for that tight launch window it appears a great deal of work must be done in the next six weeks, some of which Blue Origin engineers will be doing for the very first time.

If there are any issues and that launch window is missed, the two NASA Escapade orbiters, built by Rocket Lab, will face a two-year delay until the next window to get to Mars re-opens. At that point New Glenn will likely do this launch with a dummy payload, since it needs to get off the ground in order to fulfill other launch contracts, including a 27-launch contract with Amazon for its Kuiper satellite constellation.

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Changing Martian slope streaks

12:27 pm

Changing slope streaks on Mars
Click here, here, and here for original images.

Overview map

Time for some cool images from Mars taken over a dozen years! The three pictures above were taken, from left to right, in 2012, 2020, and 2024 and show the same exact Martian terrain. The first two pictures were photographed by the lower resolution context camera on Mars Reconnaissance Orbiter (MRO). The rightmost picture was taken on May 20, 2024 by MRO’s high resolution camera.

The white dot on the overview map to the right marks the location, in the middle of the vast lava flood plains found between Mars’ giant volcanos and north of the Medusae Fossae Formation, the largest volcanic ash deposit on Mars. The 1,200-foot-high mesa pictured above, its peak indicated by the red dot, is part of a group of such mesas that either represent the peaks of a mountain range now mostly buried by lava, or volcanic vents pushed up when those eruptions were occurring more than a billion years ago.

The focus of these pictures however is not volcanism, but the numerous slope streaks seen on the mesa slopes. Note how the 2012 earliest streaks are still visible in 2024, but have faded. Note also how there appears to have been no new streaks since 2020.

Slope streaks are a geological feature unique to Mars that at the moment remain unexplained. At first glance they appear to be a landslide of some kind, but years of orbital study has shown they do not change the topography at all, they never have debris piles at their base, and the streaks even sometimes actually flow up and over small rises in the slopes. They occur randomly throughout the year, and as seen above, over time fade.

Recent research has suggested their formation is related to dust avalanches triggered by dust storms, conclusions that are strengthened by the fact that slope streaks are generally found on dusty slopes, which in this case makes sense as the location is in the dry Martian tropics. That these dust avalanches do not change the topography at all, merely staining it, while sometimes actually flowing up and over rises, illustrates how Mars’ one-third gravity and thin, cold atmosphere makes things happen that are impossible on Earth.

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NASA leans toward launching Europa Clipper as scheduled, despite transistor issue

9:26 am

Though the final decision will be made in early September, NASA revealed today in a short post that management is leaning towards launching the multi-billion Europa Clipper mission as scheduled on October 10, 2024, despite a very recently discovered transistor issue where the transistors were not properly hardened in construction for the harsh radiation environment surrounding Jupiter.

The next major milestone for Clipper is Key Decision Point E on Monday, Sept. 9, in which the agency will decide whether the project is ready to proceed to launch and mission operations. NASA will provide more information at a mission overview and media briefing targeted for that same week.

The Europa Clipper mission team recently conducted extensive testing and analysis of transistors that help control the flow of electricity on the spacecraft. Analysis of the results suggests the transistors can support the baseline mission. [emphasis mine]

The highlighted sentence suggests NASA officials have weighed the option between launching on time with a limited ability to do science once at Jupiter versus delaying the launch years to fix the transistors, and are now favoring the former option. The cost of delay would be high and long, and NASA officials might believe the bad press for that option would be much greater than a mission that only achieves its bare minimum results. For example, to admit publicly that NASA installed transistors that were not space-hardened when that necessity has been known about since the 1960s would be as embarrassing to the agency as it was for Boeing when it discovered it had installed flammable tape in its Starliner capsule. NASA management might be leaning to letting a flawed multi-billion dollar project launch, knowing its capabilities are quite limited, in order to avoid that embarrassment.

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Evidence of Martian near-surface ice in an unusual location

11:48 am

Evidence of Martian near-surface ice in an unusual location
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 27, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled merely as a terrain sample, it was likely taken not as part of any specific research request, but to fill a gap in the camera’s picture-taking schedule so as to maintain its proper temperature.

The picture however shows features that help confirm earlier research into the near-surface ice believed to permeate Mars’ middle latitudes. The knobby flat terrain both inside and outside of the crater resembles what scientists have labeled “brain terrain”, an as-yet unexplained geological feature unique to Mars and usually associated with near-surface ice and the glacial features found above 30 degrees latitude.

This 1.4-mile-wide unnamed crater is located at 40 degrees north latitude, so expecting near-surface ice or glacial features here is not unreasonable. The location however is different for other reasons, that make this data more intriguing.
» Read more

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Webb finds six exoplanets, all flying in interstellar space without a star

11:11 am

Astronomers using the Webb Space Telescope have discovered six different planets ranging in mass 5 to 10 times that of Jupiter, all unattached to any star or solar system.

The most intriguing of the starless objects is also the lightest, having an estimated mass of five Jupiters (about 1,600 Earths). The presence of a dusty disk means the object almost certainly formed like a star, as space dust generally spins around a central object in the early stages of star formation, said Langeveld, a postdoctoral researcher in Jayawardhana’s group.

All of these starless planets likely formed like this one, coalescing like a star does but unlike a star never having enough mass to ignite.

The astronomers are next going to attempt to detect the atmosphere’s of these rogue exoplanets, though it is not clear exactly how they will do this unless one of the exoplanets just happened to transit across a more distant star, something that simply does not happen very often.

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A real whirlpool in space

9:52 am

A real whirlpool in space
Click for original image.
Cool image time! The picture above, cropped to post here, was taken by the Hubble Space Telescope as part of a survey of nearby galaxies that have what astronomers call an Active Galactic Nuclei (AGN), because the supermassive black hole at the center is devouring nearby material at a great rate and thus producing high energy emissions as it does so.

Many active galaxies are known to astronomers at vast distances from Earth, thanks to the great brightness of their nuclei highlighting them next to other, dimmer galaxies. At 128 million light-years from Earth, UGC 3478 is positively neighbourly to us. The data used to make this image comes from a Hubble survey of nearby powerful AGNs found in relatively high-energy X-rays, like this one, which it is hoped can help astronomers to understand how the galaxies interact with the supermassive black holes at their hearts.

The bottom line is that this spiral galaxy literally is a whirlpool, the entire galaxy spiralling down into that massive black hole in its center. One cannot help wondering why such galaxies don’t end up eventually getting completely swallowed by that black hole.

Or maybe they do, and we don’t see such things because all that is left is a supermassive black hole that emits no light or energy at all, a dark silent ghost traveling between the galaxies unseen and undetectable.

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First high resolution images released from Juice’s fly-by of the Earth & Moon

9:34 am

Juice's high resolution view of the Moon
Click for original image.

The Italian science team that runs the high resolution camera on the asteroid probe Juice have now released that camera’s first images, taken to test its operation during the spacecraft’s close fly-by of both the Moon and then the Earth a week ago.

The picture to the right, cropped, reduced, and sharpened to post here, shows the Moon’s surface during that close fly-by, which got within 435 miles. The camera is dubbed Janus, and was developed by Italy and operated by the Italian National Institute for Astrophysics.

JANUS will study global, regional and local features and processes on the moons, as well as map the clouds of Jupiter. It will have a resolution up to 2.4 m per pixel on Ganymede and about 10 km per pixel at Jupiter.

The main aim of JANUS’s observations during the lunar-Earth flyby was to evaluate how well the instrument is performing, not to make scientific measurements. For this reason, JANUS took images with various camera settings and time intervals – a bit like if you’re going out to test a DSLR camera for the first time. In some cases, researchers intentionally ‘blurred’ the images so that they can test out resolution recovery algorithms. In other cases, they partially saturated the image to study the effects induced on the unsaturated areas.

As can be seen by the sample image above, the test images appear to have demonstrated that Janus will function as planned when Juice arrives in orbit around Jupiter in 2031 in order to study that gas giant’s upper atmosphere as well as its larger icy moons, Ganymede, Calisto, and Europa.

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Finding beauty on Mars in all the strange places

12:08 pm

Overview map

Beauty on Mars
Click for original image.

Cool image time! The picture to the right, cropped to post here, was taken on May 23, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The white dot in the inset of the overview map above indicates the location on Mars, smack dab in the middle of the 2,000-mile-long mid-latitude strip that I call glacier country, because practically every close-up image of this region shows glacial features.

This picture is no exception. The arrows in the inset show the downhill grade, falling about 1,700 feet across the entire inset. That grade is a reflection of the transition that takes place in this glacier country from the cratered southern highlands to the northern lowland plains.

I decided to crop the image at full resolution — showing only a tiny portion — because to my eye these curving linear grooves, produced naturally as Mars’ climate cycles cause glaciers to shrink and then grow repeatedly so that each cycle lays down a new line while squeezing the previous lines, are almost like a work of art. This might be nothing more than a glacier on an alien planet, but nature has caused it to form a very beautiful picture.

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Chinese scientists find method to extract water from Chang’e-5 lunar samples

12:04 pm

Proposed concept for extracting water from lunar regoilth
Proposed concept for extracting water from
lunar regoilth

Chinese scientists have found that by heating Chang’e-5 lunar samples to 1,700 degrees Fahrenheit it is possible to extract a significant amount of water. From the paper’s abstract:

FeO and Fe2O3 are lunar minerals containing Fe oxides. Hydrogen (H) retained in lunar minerals from the solar wind can be used to produce water. The results of this study reveal that 51–76 mg of H2O can be generated from 1 g of LR [lunar regolith] after melting at temperatures above 1200 K. This amount is ∼10,000 times the naturally occurring hydroxyl (OH) and H2O on the Moon. … Our findings suggest that the hydrogen retained in LR is a significant resource for obtaining H2O on the Moon, which are helpful for establishing scientific research station on the Moon.

A video in Chinese (hat tip BtB’s stringer Jay) that describes this research can be found here. (If any of my readers understands Chinese and can provide a translation of this video’s narration, I would be very grateful.) It includes an artist’s rendering (screen capture to the right) showing how such a system on the Moon could work to extract water from the soil. Sunlight would be focused by a lensed mirror into a glass-domed container, heating the ground. The water would evaporate, condense on the glass and be sucked into a tube that would transfer it to a water tank.

This design is of course very simple and preliminary. According to Jay, “They need to heat the soil to 1000℃ (1832°F) to get the iron oxide in the lunar soil to split, the oxygen combines with hydrogen to make water and iron (melting point of iron is about 1500℃). You will need a nuclear reactor to produce that much power for an inductive furnace to get that hot. Doing the calculation, it would take about 245kw to heat up a metric ton of dirt in one hour to a 1000℃ degrees. It could be done slower over 24 hours at 10kw.”

Despite the technical difficulties getting such equipment operational on the Moon, that this research suggests water can be produced practically anywhere on the lunar surface is signficant. It suggests that even if no easily accessible water ice is found in the permanently shadowed craters at the poles, lunar bases still have viable options for obtaining water, and they don’t have even be at the poles.

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The massive scale of Mars’ biggest canyon

12:24 pm

Overview map

The south rim of Valles Marineris
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on May 24, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Labeled merely a “terrain sample” by the camera team, it was likely taken not as part of any particular research project, but to fill a gap in the picture-taking schedule in order to maintain the camera’s proper temperature.

When the camera team needs to do this, they try to pick interesting targets within the required timeframe. Sometimes they succeed, sometimes not. In today’s example, they succeeded quite well. As shown by the overview map above, this picture captures (as indicated by the rectangle) the top of the southern rim of Valles Marineris, the biggest canyon on Mars and quite possibly the biggest in the entire solar system.

For scale, the drop from the rim to the low point in this picture is about 9,000 feet. That’s a 1,000 feet more than the drop from the north rim of the Grand Canyon to the canyon bottom at the Colorado River. In Valles Marineris however our descent has barely begun. To get to the bottom of the southern canyon here you still need to drop 15,000 more feet, for a total descent of 24,000 feet, an elevation change similar to most of the mountains in the Himalayas.

Nor are you yet at the bottom. If you climb over the ridge of 18,000-foot-high mountains that bisect Valles Marineris at this point, you can drop down even further, to a depth 31,000 feet below the southern rim.

Mount Everest is just over 29,000 feet high, which means if placed inside Valles Marineris is peak would still sit 2,000 feet below the rim.

The photo itself highlights part of the erosion process that formed Valles Marineris. This is the dry tropics, so no water was involved in shaping this terrain for many eons. Instead, what appear to be flows within the hollows is alluvial fill, material that over time breaks off and rolls downhill, filling the slopes below. Erosion will grind this material into smaller particles, so given enough time it flows almost like sand.

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Pragyan data confirms theory that the Moon’s surface was once largely covered with molten lava oceans

10:03 am


Vikram as seen by Lunar Reconnaissance Orbiter.
Click for interactive map. To see the original
image, go here.

Data from India’s Pragyan lunar rover that landed in the high southern latitudes of the Moon in August 2023 has now confirmed the theory that the Moon’s surface was once largely covered with molten lava oceans.

Santosh Vadawale, an X-ray astronomer at the Physical Research Laboratory in Ahmedabad, India, and his colleagues analysed radiation data collected by the APXS [one of Pragyan’s instruments], and used this information to identify the elements in the regolith and their relative abundances, which, in turn, revealed the soil’s mineral composition. The team found that all 23 samples comprised mainly ferroan anorthosite, a mineral that is common on the Moon. The results were reported in Nature today.

“It’s sort of what we expected to be there based on orbital data, but the ground truth is always really good to get,” says Lindy Elkins-Tanton, a planetary scientist at Arizona State University in Tempe.

Previous landers obtained similar results. However, the Chandrayaan-3 samples are the first from the subpolar region: previous landers visited equatorial and mid-latitude zones. Together, this suggests that the composition of the regolith is uniform across the Moon’s surface.

These results are no surprise, but they confirm the global nature of the Moon’s early molten history. More important, they demonstrate that India now has the capability to send landers and rovers to other planets that are also capable of doing real research.

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The North Star has spots!

9:38 am

The spoted surface of Polaris
Click for original image.

Astronomers using an array of six ground-based telescopes have obtained best new data of Polaris, the North Star, including the first rough image of its surface, and discovered sunspots on its surface.

You can read the paper here [pdf]. The image to the right, taken from figure 4 of the paper, shows the surface as seen by the telescopes over two nights in April 2021. Polaris is what astronomers call a Cepheid variable star, which changes brightness on a very precise schedule as its diameter grows and shrinks. In the case of Polaris, that variation is four days long. The star’s brightness itself varies only slightly, and over the decades has even at times appeared to cease its variations.

As the true brightness of Cepheids is very predictable based on their pulse rate, these stars are one of the main tools astronomers use to determine distances to other galaxies. Knowing more about them thus has great importance to cosmological research.

The orbital motion showed that Polaris has a mass five times larger than that of the Sun. The images of Polaris showed that it has a diameter 46 times the size of the Sun.

The biggest surprise was the appearance of Polaris in close-up images. The CHARA observations provided the first glimpse of what the surface of a Cepheid variable looks like. “The CHARA images revealed large bright and dark spots on the surface of Polaris that changed over time,” said Gail Schaefer, director of the CHARA Array. The presence of spots and the rotation of the star might be linked to a 120-day variation in measured velocity.

The researchers plan to take regular images again of Polaris to better track the changes to its surface.

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Juice completes Earth fly-by, heads for Venus fly-by

9:07 am

Earth as seen by Juice
Earth as seen by Juice during fly-by.
Click for original image.

The European probe Juice yesterday successfully completed a close fly-by of the Earth and was thus successfully slingshoted on its way to its next fly-by, of Venus, on its way to Jupiter.

This fly-by was actually a double event. First Juice zipped past the Moon the day before, coming within 435 miles. Then, only one day later it passed the Earth at a distance of 4,230 miles, thus completing the first dual fly-by of the both the Earth and the Moon.

The flyby of the Moon increased Juice’s speed by 0.9 km/s relative to the Sun, guiding Juice towards Earth. The flyby of Earth reduced Juice’s speed by 4.8 km/s relative to the Sun, guiding Juice onto a new trajectory towards Venus. Overall, the lunar-Earth flyby deflected Juice by an angle of 100° compared to its pre-flyby path.

The inherently risky flyby required ultra-precise, real-time navigation, but is saving the mission around 100–150 kg of fuel. In the month before the flyby, spacecraft operators gave Juice slight nudges to put it on exactly the right approach trajectory. Then they tracked Juice 24/7 between 17–22 August.

The Venus fly-by will occur in August 2025, followed by additional Earth flys in September 2026 and January 2029. The spacecraft will finally arrive in Jupiter orbit in July 2031, where it is designed to study the large icy moons (Europa, Gandymede, and Calisto) of that gas giant.

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What the heck caused these cones to align on Mars?

2:48 pm

Another
Click for original image.

Time for another “What the heck?” cool image! The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 23, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels as “longitudinally aligned cones”.

To my eye the cones visibile in this picture seem more aligned latitudinally, to the east-west, instead of longitudinally, north-south, but the larger view in the inset on the overview map below shows that on a larger scale, the cones do appear aligned in a north-south direction.

Either way, this is one of those photos from Mars orbit that leaves me entirely baffled. The cones and the flow feature that cuts across the middle of the image might be either volcanic or glacial, but it is beyond my pay grade to explain what caused this patch of aligned cones.
» Read more

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Juice completes fly-by of Moon

9:58 am

Juice's view of the Moon
Click for original image.

Europe’s Juice probe to Jupiter yesterday successfully completed its close fly-by of the Moon, shifting its path as it prepares for a close fly-by of the Earth today.

The picture to the right, cropped, reduced, and sharpened to post here, was taken during yesterday’s flyby. At its closest approach Juice was only 435 miles above the lunar surface. It will pass the Earth today at a distance of 4,230 miles.

If the Earth fly-by today is successful, Juice will then do flybys of Venus in August 2025, Earth in September 2026, and Earth again in January 2029, arriving in Jupiter orbit in July 2031, where it is designed to study the large icy moons (Europa, Gandymede, and Calisto) of that gas giant.

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Mining Mars

12:08 pm

Mining Mars
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 22, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The picture’s focus of study is the bright strip running diagonally across the center, which the scientists label as a “linear feature exposure of infrared-bright material.”

This bright strip with all the swirls of alternating light and dark terrain is a fissure about 80 feet deep. What is interesting is that the parallel bright features to the north and south are actually ridges, not depressions, even though there appears to be some resemblance between them all. (Note that the patches of very thin parallel lines are likely ripple dunes sitting on top of the topography.)

So, what created this fissure? And why is its inner surface so strange? As is usually the case, a wider look provides some clues.
» Read more

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Martian gullies flowing down to a Martian river of ice

11:30 am

Gullies on cliff wall
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on May 16, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The scientists label this as “gullies previously identified in the walls of Harmakhis Vallis.” The gullies are obvious, the series of erosion features on the cliff wall. The cliff itself drops about 2,800 feet from the rim to the floor, and also appears to have internal horizontal layers that the gullies cut through.

What causes the gullies? Planetary scientists have a number of theories, none of which appear to explain the gullies everywhere on the Martian surface. They all appear in the mid-latitudes, where the most glaciers on Mars are found, and appear to be related to ice or frost freeze-thaw processes, with some gullies actually very ancient and formed when the planet’s rotational tilt was significantly different.
» Read more

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New data continues to refine the margin of error for the Hubble constant

9:45 am

The uncertainty of science: New data using the Webb Space Telescope’s spectroscopic capabilities has provided a more refined measure of the expansion rate of the universe, dubbed the Hubble constant.

According to previous research, that rate could be anywhere from 67.4 to 73.2 kilometers per second per megaparsecs, depending on whether you rely on data from the Planck orbiter or that of the Hubble Space Telescope. Though this difference appears reasonable considering the uncertainties and assumptions that go into research that determines both numbers, astronomers have been unhappy with the difference. The numbers should match and they don’t.

Now new data from Webb suggests this difference really is nothing more than the margin of error caused by the many uncertainties and assumptions involved. That new Webb data measured the Hubble constant using three different methods, all similar to that used by Hubble, and came up with 67.85, 67.96, and 72.04, all in the middle of the previous two numbers from Hubble and Planck.

In other words, all the data is beginning to fall within this margin of error.

Astronomers are without doubt still going to argue about this, but it does appear that the research is beginning to coalesce around an approximate number. More important, in terms of cosmology these results confirm the theory that the expansion of the universe is accelerating (dubbed “dark energy” simply because it needs a name), since they confirm the method used to measure that expansion rate in the very distant universe.

Keep your minds open however. There remain many questions and uncertainties with all these conclusions. Nothing is settled, nor will it be likely for decades if not centuries.

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Was the Chicxulub bolide 65 million years ago an asteroid from beyond Jupiter?

9:21 am

According to a new study, the Chicxulub bolide that impacted the Yucatan 65 million years ago and is thought to have been a major cause of the extinction of the dinosaurs was likely a carbonaceous-type asteroid from beyond Jupiter.

The researchers attempted to pinpoint the nature of that bolide by analyzing the isotope samples from the thin layer of materials found worldwide that corresponds to the impact (dubbed the K-Pg boundary) as well number of different impact samples from different layers.

To address these questions, Mario Fischer-Gödde and colleagues evaluated ruthenium (Ru) isotopes in samples taken from the K-Pg boundary. For comparison, they also analyzed samples from five other asteroid impacts from the last 541 million years, samples from ancient Archaean-age (3.5 – 3.2 billion-years-old) impact-related spherule layers, and samples from two carbonaceous meteorites.

Ficher-Gödde et al. found that the Ru isotope signatures in samples from the K-Pg boundary were uniform and closely matched those of carbonaceous chondrites (CCs), not Earth or other meteorite types, suggesting that the Chicxulub impactor likely came from a C-type asteroid that formed in the outer Solar System. They also rule out a comet as the impactor. Ancient Archean samples also suggest impactors with a CC-like composition, indicating a similar outer Solar System origin and perhaps representing material that impacted during Earth’s final stages of accretion. In contrast, other impact sites from different periods showed Ru isotope compositions consistent with S-type (salicaceous) asteroids from the inner Solar System.

My headline poses this result as a question because these results are unconfirmed, and based on a very small sample of data. Nonetheless, this research not only gives us a better idea of the nature of the Chicxulub impactor, it does the same for a number of other important past impacts. That data in turn will help theorists refine their theories describing the early formation history of the solar system.

Sidebar: As always, there are numerous stories today in the mainstream press going ga-ga over this paper and declaring with certainty the utter truth of its conclusions. This of course is junk reporting, as there is no utter truth here, only some educated speculation based on some new data.

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Astronomers discover a nearby star moving so fast it could even escape the Milky Way

10:20 am

Astronomers, both professional and amateur, have discovered a nearby star only 400 light years away that is moving so fast, 1.3 million miles per hour (almost three times faster than the Sun), it might very well escape the Milky Way and fly into intergalactic space in the far future.

The star, named CWISE J124909+362116.0 (or “J1249+36” for short), was first spotted by some of the over 80,000 citizen science volunteers participating in the Backyard Worlds: Planet 9 project, who comb through enormous reams of data collected over the past 14 years by NASA’s Wide-field Infrared Survey Explorer (WISE) mission. This project capitalizes on the keen ability of humans, who are evolutionarily programmed to look for patterns and spot anomalies in a way that is unmatched by computer technology. Volunteers tag moving objects in data files and when enough volunteers tag the same object, astronomers investigate.

J1249+36 immediately stood out because it was moving at about .1 percent the speed of light.

The star itself is either a very low mass red dwarf, or possibly a brown dwarf that never quite had enough mass to ignite as a star.

You can read the research paper here [pdf]. The researchers posit two possible explanations for the star’s speed. Either it was once part of a binary and thrown out when its white dwarf companion exploded as a supernova, or was once located in a densely packed globular cluster, where the interaction with other stars or even black holes could have flung it away.

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The future route of Perseverance out of Jezero Crater

10:01 am

Perseverance's future route
Click for original image.

The science team for the Mars rover Perseverance today outlined the planned route they intend to follow to bring the rover out of Jezero Crater.

The map to the right shows that route in red, with the rover presently at the upper right. Though Perseverance presently sits inside Neretva Vallis, which is the channel that cuts through the rim of the crater through which poured the delta material the rover has been sampling since landing, the route out of the crater will instead head south and west, crossing over the rim.

NASA’s Perseverance Mars rover will soon begin a monthslong ascent up the western rim of Jezero Crater that is likely to include some of the steepest and most challenging terrain the rover has encountered to date. Scheduled to start the week of Aug. 19, the climb will mark the kickoff of the mission’s new science campaign — its fifth since the rover landed in the crater on Feb. 18, 2021.

…Two of the priority regions the science team wants to study at the top of the crater are nicknamed “Pico Turquino” and “Witch Hazel Hill.” Imagery from NASA’s Mars orbiters indicates that Pico Turquino contains ancient fractures that may have been caused by hydrothermal activity in the distant past.
Rover looking back at the “Bright Angel” area

Orbital views of Witch Hazel show layered materials that likely date from a time when Mars had a very different climate than today. Those views have revealed light-toned bedrock similar to what was found at “Bright Angel,” the area where Perseverance recently discovered and sampled the “Cheyava Falls” rock, which exhibits chemical signatures and structures that could possibly have been formed by life billions of years ago when the area contained running water.

For Perseverance’s recent travels, go here.

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Webb data suggests the possibility of ice and hydrated minerals on surface of Psyche

9:33 am

Using the Webb Space Telescope, astronomers have detected evidence of hydrated minerals and even possibly a very tiny amount of water ice on the surface of the metal asteroid Psyche.

The Webb data point to hydroxyl and perhaps water on Psyche’s surface. The hydrated minerals could result from external sources, including impactors. If the hydration is native or endogenous, then Psyche may have a different evolutionary history than current models suggest. “Asteroids are leftovers from the planetary formation process, so their compositions vary depending on where they formed in the solar nebula,” said SwRI’s Dr. Anicia Arredondo, another co-author. “Hydration that is endogenous could suggest that Psyche is not the remnant core of a protoplanet. Instead, it could suggest that Psyche originated beyond the ‘snow line,’ the minimum distance from the Sun where protoplanetary disc temperatures are low enough for volatile compounds to condense into solids, before migrating to the outer main belt.”

However, the paper found the variability in the strength of the hydration features across the observations implies a heterogeneous distribution of hydrated minerals. This variability suggests a complex surface history that could be explained by impacts from carbonaceous chondrite asteroids thought to be very hydrated.

You can read the research paper here [pdf]. The actual amount of water possible is at most 39 parts per million and is also an order of magnitude lower than that found on the Moon, which strongly suggests that it comes from outside sources, such as impacts from other asteroids, not from the inherent geological history of Psyche itself.

The uncertainties of this research, which are large, which should be resolved when the probe Psyche, launched last year, reaches the asteroid Psyche in August 2029.

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Intuitive Machines wants to land VIPER rover on Moon

9:04 am

VIPER's planned route on the Moon
VIPER’s now canceled planned route at the Moon’s south pole

The lunar lander startup Intuitive Machines has now revealed it is putting together an industry partnership to bid on flying NASA’s VIPER lunar rover on its own largest lander, still under development.

In an Aug. 13 earnings call about its second quarter financial results, Intuitive Machines executives said they were planning to respond to a request for information (RFI) that NASA issued Aug. 9 seeking input from companies and organizations interested in taking over the Volatiles Investigating Polar Exploration Rover (VIPER) mission that the agency said in July it would cancel.

Steve Altemus, chief executive of Intuitive Machines, said on the call that his company, which also responded to an earlier call for “expressions of interest” from NASA regarding VIPER, is working with other companies, universities and international partners on responding to NASA’s RFI. He did not identify any of those prospective partners.

…NASA, in its RFI, said that prospective partners would be responsible for the costs of any final testing and other work on the rover itself, as well as delivering it to the lunar surface and operating it once there. NASA, in its July 17 announcement that it would cancel VIPER, said the agency would save at least $84 million by halting work now on the rover, now complete and undergoing environmental testing.

Whether this company can raise the capital to finish this mission, now that NASA has said it cannot, remains unclear. That it is trying, and NASA is not, illustrates however why NASA should get out of the business of building anything and just buy it from the private sector. NASA’s attempt to build VIPER went 3Xs over budget and is considerably behind schedule. Now the private sector see profits in finishing the job, which will in turn save the agency considerable money. Imagine if NASA had done this from the beginning. The savings would have been even greater, and VIPER might right now be even closer to launch.

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Buried peaks in a sea of Martian sand

12:46 pm

Buried peaks in a sea of sand
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Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 13, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the MRO science team labels as “streamlined features”, though that doesn’t seem to me to be the best description.

Granted, the prevailing winds, from the northeast to the southwest, appear to pushing the sand dune fields to the southwest. The dark line — created recently by a dust devil — indicates the wind direction. The mesas, from 100 to 200 feet high, do not however appear very streamlined. Instead, they simply look like they are poking up through this sea of sand and dunes, with the wind able over time to successfully push that sand uphill a hundred-plus feet into the saddle between the mesas.

The overview map below provides some context and possibly an explanation, though not a very conclusive one.
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More bad journalism, this time about a hypothesized “underground ocean” on Mars

10:14 am

How today's journalists analyze potential stories
How today’s journalists analyze potential stories

Today’s example of modern bad journalism from our dismal mainstream press concerns a paper published yesterday in the journal of the National Academy of Sciences describing the possibility of liquid water in the Martian “mid-crust,” based on InSight seismological data and computer modeling.

I read the paper yesterday and decided that there really wasn’t much there. While the data suggests a lot of liquid water might be saturated within the fractured rocks of this deep underground crustal layer six to twelve miles down, the paper was based on many assumptions and had many uncertainties. It is also not confirmed by other researchers, and remains nothing more than educated speculation at this point.

Not surprisingly, our ignorant mainstream press today has immediately declared the discovery of a vast underground ocean on Mars, ready for the taking and possibly harboring life!
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The strange carbon dioxide ice cap of Mars’ south pole

12:33 pm

The strange carbon dioxide cap of Mars
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Cool image time! The picture to the right, cropped to post here, was taken on July 1, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The image is labeled simply as a “terrain sample,” which usually means it was taken not as part of any specific research project but to fill a gap in the picture-taking schedule in order to maintain the camera’s proper temperate. When the camera team needs to do this, they try to picture interesting features availabe at that time slot. Sometimes the image is boring. Sometimes it is surprisingly interesting.

In this case the picture is the latter, and certainly quite alien. The curly parallel dark lines appear to be grooves, and seem to have ripple dunes within them, as if the only dust here got trapped in those low spots. It is also possible that the dunes are frozen and ancient, and are only being revealed as the top layer in each groove goes away.

What could possibly explain what we are looking at? The overview map below gives only a clue.
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A galaxy with a ring

9:34 am

A galaxy with a ring
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Cool image time! The photo to the right, cropped, reduced, and sharpened to post here, was taken by the Hubble Space Telescope, and appears part of a long term survey of nearby ringed galaxies. From the caption:

MCG+07-07-072 has quite an unusual shape, for a spiral galaxy, with thin arms emerging from the ends of its barred core to draw a near-circle around its disc. It is classified, using a common extension of the basic Hubble scheme, as an SBc(r) galaxy: the c denotes that its two spiral arms are loosely wound, each only performing a half-turn around the galaxy, and the (r) is for the ring-like structure they create. Rings in galaxies come in quite a few forms, from merely uncommon, to rare and astrophysically important!

Lenticular galaxies are a type that sit between elliptical and spiral galaxies. They feature a large disc, unlike an elliptical galaxy, but lack any spiral arms. Lenticular means lens-shaped, and these galaxies often feature ring-like shapes in their discs. Meanwhile, the classification of “ring galaxy” is reserved for peculiar galaxies with a round ring of gas and star formation, much like spiral arms look, but completely disconnected from the galactic nucleus – or even without any visible nucleus! They’re thought to be formed in galactic collisions.

This galaxy is about 320 million light years away, and is also known as Abell 426. Though astronomers think that these various shapes of galaxies, from barred to lenticular to ringed, are formed from a variety of galactic collusions and interactions with each galaxy’s nucleus, that remains nothing more than an educated guess. The complexity of galaxy evolution, involving billions of years and millions of stars, is barely in its infancy, and requires a lot of assumptions because our observations only involves a mere nanosecond in that grand history.

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Are these Martian terraced mesas or pits?

2:52 pm

Are these Martian pits or mesas?
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Cool image time! The picture to the right, cropped, reduced, and enhanced to post here, was taken on July 2, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). I have purposely enhanced the contrast to bring out the strangely shaped and terraced features.

What I cannot figure out from any data available to me is whether these terraced features are mesas rising up, or pits descending down. The resolution in the global mosiac of Mars created both from MRO’s context camera and its elevation data is simply not good enough. It suggests these are pits, but the sunlight is coming from the west, which based on the shadows suggest these could be pits or mesas.

In fact, the dark lines that appear to distinguish the terraces might not be shadows at all, but simply darker material that contrasts with the lighter material on each side.
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