Tag: science

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.

8 comments

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.

0 comments

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.

0 comments

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.

4 comments

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.

1 comment

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

1 comment

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.

1 comment

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

0 comments

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

2 comments

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.

3 comments

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.

2 comments

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.

11 comments
1 … 66 67 68 69 70 … 729