Tag: science

Another tourist site for future Starship passengers on Mars

12:16 pm

Another tourist site for future Starship passengers on Mars
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 11, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows the northwest quadrant of a 7-mile-wide crater whose western rim was smashed by the later impact that created a smaller 2.8-mile-wide crater.

What makes this location interesting is what fills both craters, and how that material appears to flow through a gap in the smaller crater. The color strip suggests the peaks of the rim and small knobs are dust-covered, while the flat materials below are either “coarser-grained materials” that might also have elements of frost or ice within them. The science team thinks ice is involved, having labeled this picture “Ice Flow Features between Craters.”
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Host galaxies for two quasars in early universe detected for the first time

10:06 am

Quasar and host galaxy
One of the quasars, with its light subtracted on the right,
revealing the host galaxy. Click for original image.

The uncertainty of science: Using data from both the infrared Webb Space Telescope and the Subaru optical telescope in Hawaii, astronomers have observed for the first time the host galaxies of two quasars that formed less than a billion years after the Big Bang.

Just a few months after JWST started regular operations, the team observed two quasars, HSC J2236+0032 and HSC J2255+0251, at redshifts 6.40 and 6.34 when the universe was approximately 860 million years old, both of which were discovered using Subaru Telescope’s deep survey program. The relatively low luminosities of these quasars made them prime targets for measuring the properties of their host galaxies.

The images of the two quasars were taken at infrared wavelengths of 3.56 and 1.50 microns with JWST’s NIRCam instrument, and the host galaxies became apparent after carefully modeling and subtracting glare from the accreting black holes. The stellar signature of the host galaxy was also seen in a spectrum taken by JWST’s NIRSPEC for J2236+0032, further supporting the detection of the host galaxy.

Photometric analyses found that these two quasar host galaxies are massive, measuring 130 and 34 billion times the mass of the Sun, respectively. Measuring the speed of the turbulent gas in the vicinity of the quasars from the NIRSPEC spectra suggests the black holes that power them are also massive, measuring 1.4 and 0.2 billion times the mass of the Sun. The ratio of the black hole to host galaxy mass is similar to those of galaxies in the more recent past, suggesting that the relationship between black holes and their hosts was already in place 860 million years after the Big Bang. [emphasis mine]

Normally, quasars are so bright the host galaxy is obscured. Computer modeling that subtracted the quasar’s light produced the host galaxy image on the right.

The highlighted sentence raises intriguing questions again about the Big Bang. Webb is once again finding evidence that the early universe quickly became like today’s universe, much faster than expected by cosmologists.

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Spring near the Martian north pole

12:28 pm

Spring near the Martian north pole
Click for original image.

Overview map

Cool image time! The picture above, rotated, reduced, and brightened slightly to post here, was taken on April 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It cuts a swath across an eleven-mile-wide crater only about 500 miles from the edge of Mars’ north pole ice cap.

The overview map to the right marks its location, as indicated by the white dot on the right edge of the map. The inset shows the soft and likely icy nature of the surface in which this impact occurred. The crater resulted in a secondary outside ripple, that quickly hardened after impact.

The image was taken during spring, shortly after the sun’s light hit this crater. The cracks in the ice indicate long term sublimation that is slowly reducing the amount of water ice inside the crater. Like mud cracks in the desert after a puddle has evaporated, the ice here is cracking to produce polygon fractures.

It is also very likely that everything here is coated with a thin mantle of clear dry ice, deposited as snow from the atmosphere in the winter and then sublimating away with the coming of spring. That spring dry ice sublimation is likely ongoing, and this picture is probably an attempt by scientists to detect that process.

Why the surface colors shift from aquablue to orange might have to do with that sublimation process, or it might be revealing areas covered with dust (orange). That the northern parts of the strip is blue and the southern parts orange suggests the former. Or not. I don’t have enough information to answer this question with any confidence.

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Zhurong data shows very weak magnetic field at landing site

10:17 am

Using data accumulated by Zhurong while it was still rovering on Mars, Chinese scientists have determined that the weak Martian magnetic field at Utopia Basin where the rover landed was very weak, much weaker than expected.

Results from NASA’s Mars’ lander InSight, which landed about 2,000 km southeast of Zhurong, have revealed that the crustal magnetic field at InSight’s landing site was an order stronger than that inferred from orbital measurement. Measurements from Zhurong, however, revealed the opposite result, with the average intensity an order less than that inferred from orbit.

The weak field suggests that the crust under Utopia Basin was never magnetized, or was demagnetized by some large later impact.

Meanwhile, no word on Zhurong itself, which either remains in hibernation or has died due to lack of power caused by the dusty Martian winter.

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Surprise! The cost for the Mars Sample Return mission is ballooning!

10:11 am

According to NASA, the cost for the Mars Sample Return mission could possibly rise to as high as $8 to $9 billion, more than double the $3.8 billion to $4.4 billion estimated by a 2020 review.

NASA itself has recently become very silent about the project’s expected cost.

NASA officials have been careful not to give any estimates of costs for MSR in recent presentations, stating that it will wait until a formal confirmation review for the program, scheduled for the fall, before providing an official cost and schedule baseline. That will come after a series of preliminary design reviews and a review by a second independent board led by Orlando Figueroa, a former director of NASA’s Mars exploration program.

Those earlier numbers were never realistic, based on NASA’s recent track record. The cost of its big projects — Webb, SLS, Orion, Roman Telescope — always grows exponentially, once the project gets going.

This cost increase however is a serious political problem for NASA and this sample return mission, as the House is demanding major real cuts in the budgets of almost all federal agencies. While I expect NASA to survive these cuts without great harm, a program that shows out-of-control budget growth might become a target by the House, which is likely why NASA scheduled its review of the sample return mission to occur in the fall, after the House approves its next budget. Better to announce bad news as late as possible.

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China conducts parachute tests for returning asteroid sample to Earth

9:53 am

China has successfully conducted tests of the parachute design that will be used by the sample return capsule of its Tianwen-2 mission to grab samples from the near Earth asteroid dubbed 469219 Kamoʻoalewa.

The mission will launch on a Long March 3B rocket in 2025, and rendezvous with the asteroid in 2025. After getting its samples and releasing the sample return capsule, the plan is to then send Tianwen-2 to Comet 311P/PANSTARRS, arriving in the 2030s.

The probe uses fanlike solar panels, apparently copied from those used by NASA’s Lucy asteroid probe. China also has copied the touch-and-go sample grab methods used by OSIRIS-REx and Hayabusa-2, but it will also try its own original idea, to anchor to the asteroid and use drills in the probe’s landing legs.

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A northern lowland ice sheet on Mars?

9:39 am

A northern lowland ice sheet on Mars?
Click for original image.

Cool image time. The picture to the right, cropped to post here, was taken on March 14, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Dubbed simply a “terrain sample,” this image was likely taken not as part of any specific research project, but to fill a gap in the camera’s schedule in order to maintain its temperature by taking regular images. When the camera team needs to do this, they try to find interesting locations not previously photographed. Sometimes the photos turn out somewhat boring. Most of the time however they capture something very intriguing.

In this case, the intriguing feature of this picture is its stippled surface that seems to overlay a relatively flat surface underneath, with some faint covered craters visible. On top are several more recent craters that suggest either the impact landed in very soft material, thus producing little ejecta and no crater rims or the craters are not craters but sinks, places where the ground is subsiding due to some underground process.
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Webb makes first detection of one particular carbon molecule

8:42 am

The uncertainty of science: Using the Webb Space Telescope, astronomers have made the first detection of methyl cation (pronounced cat-eye-on) (CH3+) in space, located in a baby solar system the star-forming region of the Orion nebula about 1,350 light years away.

While the star in d203-506 is a small red dwarf, the system is bombarded by strong ultraviolet (UV) light from nearby hot, young, massive stars. Scientists believe that most planet-forming disks go through a period of such intense UV radiation, since stars tend to form in groups that often include massive, UV-producing stars.

Typically, UV radiation is expected to destroy complex organic molecules, in which case the discovery of CH3+ might seem to be a surprise. However, the team predicts that UV radiation might actually provide the necessary source of energy for CH3+ to form in the first place. Once formed, it then promotes additional chemical reactions to build more complex carbon molecules.

Broadly, the team notes that the molecules they see in d203-506 are quite different from typical protoplanetary disks. In particular, they could not detect any signs of water. [emphasis mine]

In the next day or so we shall likely see a number of stories in the mainstream press shouting some variation of “Webb finds key element of life!” Webb has done no such thing. It has found a carbon molecule not seen previously, which simply provides scientists another small data point in trying to understand the development of complex solar systems.

The highlighted sentences make clear the uncertainty in this field and the general shallow amount of knowledge. For example, why carbon molecules but no water, which is made up of hydrogen and oxygen, both ubiquitous throughout the universe and found in large amounts in star-forming regions?

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Determining whether a Martian crater is impact or volcanic

12:02 pm

Determining whether a Martian crater is impact or volcanic
Click for original image.

Overview map

Cool image time! The picture above, rotated, cropped, reduced, and sharpened to post here, was taken on March 22, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The camera team labeled this “Crater rim and ejecta,” which subtly reveals the picture’s scientific purpose.

The white dot on the overview map to the right indicates the location of this 15-mile-wide unnamed crater, about 150 miles northwest of where the rover Opportunity landed and traveled south to the rim of Endeavour Crater. It also shows in the inset that the crater appears to sit in the center of an upraised mound, suggesting it was formed not by impact but by volcanic processes.

This picture however says otherwise. The many small mounds and mesas to the south of the crater rim are not what one would expect on the apron of a volcano. Instead, they suggest this crater is an impact, with those mounds the eroded ejecta from that impact, now also partly buried by dust. This hypothesis is strengthened by the data from Opportunity, which found a great deal of impact ejecta during its travels, possibly from the very event that created this crater.

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A spectacular Martian glacier

11:24 am

Overview map

A spectacular Martian glacier
Click for original image.

Mars appears to be a planet filled with past surface flows, none of which are active today but all of which came from widely different geological processes. Yesterday’s Martian cool image showed the hardened remains of a lava flow on Mars. Today’s cool image shows us what might one of the best examples of the kind of glacial evidence orbital images have been finding throughout the mid-latitudes of Mars.

The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 27, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The red dot in the inset on the overview map above indicates its location on Mars, in the chaos region dubbed Protonilus Mensae that forms the central part of the 2,000-mile-long Martian region in the north mid-latitudes I dub glacier country. In this region almost every high resolution image shows evidence of glaciers, all protected by a thin layer of dust and debris so they do not sublimate away.

This particular glacier fills a canyon carved into the southern cliff of a mile-high mesa five miles by ten miles in size, and drops dramatically almost 4,700 feet in about four miles. In fact, it so epitomizes what glaciers look like that the camera team for MRO’s high resolution camera used a 2020 image to give a quick lesson on how to spot a glacier on Mars.

This 2023 picture was likely taken as part of a long term monitoring program. Though planetary scientists presently do not think the glaciers on Mars are active and moving, this assumption is not yet confirmed. Taking repeated pictures of this same glacier over time will eventually answer this question.

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More direct images released of exoplanet 87.5 light years away

9:56 am

Keck images of exoplanet over time

The Keck Observatory in Hawaii has now released its own image of the exoplanet AF Leporis b, following up the images produced by the Very Large Telescope (VLT) released in February.

The direct images Franson’s team captured revealed that AF Lep b is about three times the mass of Jupiter and orbits AF Leporis, a young Sun-like star about 87.5 light-years away. They took a series of deep images of the planet starting in December 2021; two other teams also captured images of the same planet since then.

What make the Keck observations most interesting is that they captured over time the motion of the exoplanet as it orbited its star. The two images to the right show this motion.

The paper, available here, was published today in Astrophysical Journal Letters. This particular star also has a debris disk surrounding it, suggesting it is a young solar system still in the process of forming. From the paper’s conclusion:

AF Lep joins other young planet hosts with debris disks such as β Pic, HR 8799, HD 206893, and HD 95086, reinforcing indications of a higher frequency of long-period planets orbiting stars hosting debris disks.

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Greta Thunberg: All humanity is now extinct on Earth, because we didn’t do anything about global warming

12:40 pm

Greta Thunberg speaks!
Greta Thunberg speaks!

How dare you! On June 21, 2018, Greta Thunberg informed us — as shown in her tweet to the right — that we only had five years left to stop using fossil fuels, and if we didn’t “climate change will wipe out all of humanity.”

I am hardly the only person to note this example of global warming fraudulence. Numerous reporters have also gleefully noted it, with this essay today at American Thinker by Andrea Widburg probably the most damning, not so much for noting the ignorant rantings of this uneducated high school drop-out whom the left made their icon of knowledge and top global warming expert, but for the list she provides of the endless number of other failed doomsday predictions by global warming activists and politicians.

That list was compiled in 2019, and thus it did not yet include Thunberg’s absurd prediction. Nor did it include the endless string of additional false doomsday predictions that this crowd has continued to issue in the years since, all of which I guarantee without any uncertainty will all fail, just as their hundreds of past doomsday predictions have failed.

You see, the point of those predictions was not to educate, but to instill fear, so as to then justify a power grab by the government. As Widburg concludes:
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A lava flow on a Martian lava plain

12:04 pm

A lava flow on a Martian lava plain
Click for original image.

While much of surface of the Martian equatorial regions is comprised of volcanic flood lava, the place where it is most obvious and evident is on the flanks of the three giant volcanoes of the Tharsis Bulge. Here, lava did not simple spout from surface vents to flood low-lying large areas, filling those depressions quickly almost like water. Instead it issued from vents on the slopes of those mountains, or from their calderas at their peaks, and flowed downhill almost like tsunamis of magma.

The picture to the right, rotated, cropped, reduced, and sharpened to post here, is a great example. Taken on March 11, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), it shows the foot of one such flow, frozen in place as it oozed down hill from the Arsia Mons, about 300 miles away to the northwest.
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BepiColumbo completes third Mercury flyby

9:23 am

Mercury as seen by BepiColumbo
Click for original image.

On June 19, 2023, the European Mercury orbiter BepiColumbo made the third of six planned flybys of Mercury on its way to orbit around that planet in 2025.

The closest approach was only 146 miles above the planet’s surface. Though no pictures were taken at that point because it was Mercury’s night side, as the spacecraft moved away it used one of its monitoring cameras, designed primarily to monitor the spacecraft itself, to look back at the planet. The picture to the right, cropped, reduced, and sharpened to post here, is one of the first taken. From its caption:

The image was taken at 19:49 UTC (21:49 CEST) by the Mercury Transfer Module’s monitoring camera 3, when the spacecraft was about 2536 km from the planet’s surface. Closest approach took place at 19:34 UT (21:34 CEST) on the night side of the planet at about 236 km altitude. The back of the Mercury Planetary Orbiter’s high-gain antenna and part of the spacecraft’s body is also visible in front of Mercury in this image.

Despite the dark nature of the image, several interesting geological features are seen in beautiful detail. Of particular interest is Beagle Rupes, a 600 km-long scarp that snakes over the surface. In this view it is seen cutting through a distinctive elongated crater named Sveinsdóttir, which likely got its shape from an impactor striking the surface at an angle.

The next flyby will occur on September 5, 2024.

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Looking down a canyon on Mars

9:43 am

Looking down a canyon on Mars
Click for original image.

Cool image time! The picture to the right was taken on June 17, 2023 by Curiosity’s high resolution camera, looking back down Gediz Vallis and out across the distant floor of Gale Crater, far below. The white dotted line shows the route within this image where Curiosity had previously traveled inside this canyon, coming up around that shadowed mesa and then off to the west to try to get to terrain that it had earlier retreated because it was too rough on the rover’s wheels. Its subsequent path to the spot where this picture was taken was off to the left of the image, out of view.

This picture illustrates well the steepness and roughness of the mountainous canyon through which Curiosity presently travels. The small mountains visible on the floor of Gale Crater, about sixteen miles away, are no more than 450 feet high. The floor of the crater is 1,900 feet below where Curiosity present sits.
» Read more

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A Martian crater with a wake of lava

12:47 pm

Overview map

Cool image time! Today’s cool image begins with the overview map to the right. The white dot marks its location, on the western edge of Amazonis Planitia and about 1,000 miles east of the giant shield volcano Elysium Mons.

This is a region of numerous flood lava events that appear to cover the knobby mountainous terrain that was once here. We know that past terrain was knobby because in the black outline just south of this picture the knobs are everywhere, short peaks sticking up from a very flat flood lava plain. The region is also on the northern edge of the dry equatorial regions of Mars, at 27 degrees north latitude. It is likely there is little near surface ice here.

These details will help explain the cool image itself.
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The icy mesas of Mars’ glacier country

12:06 pm

Overview map

The ice mesas of Mars' glacier country
Click for original image.

Cool image time! The picture to the right, rotated, cropped, and reduced to post here, was taken on March 25, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this image “Cross-Section of Glacier-Like Form,” probably because the mesa in the center of the picture clearly shows numerous layers as you descend from its peak to the surrounding plains, an elevation difference of about 200 feet.

The white dot about 250 miles due south of Lyot Crater on the overview map above marks the location of this mesa, inside the chaos terrain of Deuteronilus Mensae that is the western section of the 2,000 long strip in the northern mid-latitudes of Mars that I call glacier country, since practically every image, like today’s, suggests the presence of glaciers.

The oblique mosaic below, created using MRO’s context camera images, illustrates this fact even more spectacularly.
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Lightning on Jupiter

10:53 am

Lightning on Jupiter
Click for original image.

Cool image time! The picture to the right, cropped and reduced to post here, was taken on December 30, 2020 by Juno during its 31st close fly-by of Jupiter, and was enhanced and processed by citizen-scientist Kevin Gill.

In this view of a vortex near Jupiter’s north pole, NASA’s Juno mission observed the glow from a bolt of lightning. On Earth, lightning bolts originate from water clouds, and happen most frequently near the equator, while on Jupiter lightning likely also occurs in clouds containing an ammonia-water solution, and can be seen most often near the poles.

Juno was about 20,000 miles above Jupiter’s clouds when it took this picture, located at about 78 degrees north latitude.

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Scientists detect evidence of phosphorus coming from the interior of Enceladus

9:13 am

Using archival data from the Cassini orbiter, scientists have now detected the first evidence of phosphorus – a key element in the development of life on Earth – coming from the interior of the Saturn moon Enceladus.

The small moon is known to possess a subsurface ocean, and water from that ocean erupts through cracks in Enceladus’ icy crust as geysers at its south pole, creating a plume. The plume then feeds Saturn’s E ring (a faint ring outside of the brighter main rings) with icy particles.

During its mission at the gas giant from 2004 to 2017, Cassini flew through the plume and E ring numerous times. Scientists found that Enceladus’ ice grains contain a rich array of minerals and organic compounds – including the ingredients for amino acids – associated with life as we know it.

Phosphorus, the least abundant of the essential elements necessary for biological processes, hadn’t been detected until now. The element is a building block for DNA, which forms chromosomes and carries genetic information, and is present in the bones of mammals, cell membranes, and ocean-dwelling plankton. Phosphorus is also a fundamental part of energy-carrying molecules present in all life on Earth. Life wouldn’t be possible without it.

“We previously found that Enceladus’ ocean is rich in a variety of organic compounds,” said Frank Postberg, a planetary scientist at Freie Universität Berlin, Germany, who led the new study, published on Wednesday, June 14, in the journal Nature. “But now, this new result reveals the clear chemical signature of substantial amounts of phosphorus salts inside icy particles ejected into space by the small moon’s plume. It’s the first time this essential element has been discovered in an ocean beyond Earth.”

You can read the paper here. It is very important to emphasize that though phosphorus is essential for life, life in the underground ocean of Enceladus has not been discovered. The scientists have merely found evidence of this specific ingredient needed for life, suggesting that these ingredients are common in our solar system. Going from a list of ingredients to a finished dish one can eat is something else entirely.

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Drainage channel between two Martian hollows

12:01 pm

Drainage channel between two Martian hollows
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on April 28, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). Dubbed a “terrain sample” by the camera team, it was likely taken not as part of any specific research project but to fill a gap in the camera’s schedule so as to maintain that camera’s proper temperature. When they have to do this, they try to pick interesting targets, though there is no guarantee the result will be very interesting.

In this case the camera snapped what appears to be a drainage channel between two deeper hollows. The channel sits about 100 feet above the western hollow and 260 feet above the eastern hollow. This makes some sense, as the overall drainage in this region is going from the west to the east, and then to the north.
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Astronomers detect vaporized elements in atmosphere of hot Jupiter-sized exoplanet

8:23 am

Using the Gemini telescope in Hawaii, astronomers have detected several elements in atmosphere of hot Jupiter-sized exoplanet, dubbed WASP-76b, that would normally be found in rocks, but here are vaporized because the exoplanet orbits so close to its star.

In 2020 and 2021, using Gemini North’s MAROON-X (a new instrument specially designed to detect and study exoplanets), Pelletier and his team observed the planet as it passed in front of its host star on three separate occasions. These new observations uncovered a number of rock-forming elements in the atmosphere of WASP-76b, including sodium, potassium, lithium, nickel, manganese, chromium, magnesium, vanadium, barium, calcium, and, as previously detected, iron.

Due to the extreme temperatures of WASP-76b’s atmosphere, the elements detected by the researchers, which would normally form rocks here on Earth, are instead vaporized and thus present in the atmosphere in their gaseous forms. While these elements contribute to the composition of gas giants in our Solar System, those planets are too cold for the elements to vaporize into the atmosphere making them virtually undetectable.

The data not only suggests such elements exist in the solar system’s gas giants, but that such elements are common in solar systems elsewhere. That possibility increases the chances of other planets like Earth, capable of sustaining life as we know it, in addition to sustaining life as we don’t know it.

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BepiColumbo about to do third Mercury flyby

7:58 am

In its long journey to get into orbit around Mercury, BepiColumbo needs to do nine different flybys of the inner planets, with third fly-by of Mercury coming up on June 19, 2023.

The mission launched into space on an Ariane 5 from Europe’s Spaceport in Kourou in October 2018 and is making use of nine planetary flybys: one at Earth, two at Venus, and six at Mercury, to help steer into Mercury orbit.

After this flyby, the mission will enter a very challenging part of its journey to Mercury, gradually increasing the use of solar electric propulsion through additional propulsion periods called ‘thrust arcs’ to continually brake against the enormous gravitational pull of the Sun. These thrust arcs can last from a few days up to two months, with the longer arcs interrupted periodically for navigation and manoeuvre optimisation.

The spacecraft will zip past Mercury at a height of 147 miles. If all goes well, this dual orbiter mission, carrying both a European and a Japanese orbiter will arrive in 2025, beginning a planned three year mission in different complementary orbits.

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Rimstone dams in Mars’ youngest lava deposit

1:01 pm

Rimstone dams in Mars' youngest lava deposit
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on April 23, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The scientists dub the features here merely as “land forms,” probably because it is difficult to explain the origins of many of these strange features. For example, why is the half-mile-wide crater filled that knobby terrain, far different than the surrounding plains? Similarly, what caused the small meandering ridges (less than five feet high) that appear to closely resemble the cave formation called rimstone dams?

And why is this terrain so generally flat and smooth?

As usual, the overview map helps explains some of this, but not all.
» Read more

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Eroding glacier on Martian slope?

12:21 pm

Eroding glacier on Martian slope?
Click for original image.

Cool image time! The picture to the right, enhanced, cropped, reduced, and sharpened to post here, was taken on April 1, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels as “Rough Ground and Bright Exposures” on the flanks of a wide mountain range on Mars, whose highest point is about 4,400 feet higher to the northeast and about 30 miles away.

The arrow indicates the downhill grade. Notice the smooth flat areas that seem to only partially cover much rougher terrain below. To my eye this top layer resembles an Earth glacier that has partly sublimated or melted away, exposing the rougher bedrock below that has been ground and scraped by the glacier previously.

However, this is not on Earth, so assuming it is like an Earth glacier is dangerous.
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X-ray telescope on ISS develops light leak

9:59 am

The NICER X-ray telescope on ISS has developed a light leak that now limits its use during daylight hours.

The team suspects that at least one of the thin thermal shields on NICER’s 56 X-ray Concentrators has been damaged, allowing sunlight to reach its sensitive detectors.

Pending any repair attempts, observations during the daytime are now restricted to objects in the sky opposite the Sun. Night observations remain unaffected.

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Study: Long periods of weightlessness caused changes in the brain

9:55 am

Scientists studying the brains of 30 astronauts who spent from two weeks to one year on ISS have found that the longer a person stayed in weightlessness the greater the changes caused in the brain, and the longer it takes to recover.

Their findings, reported today in Scientific Reports, reveal that the brain’s ventricles expand significantly in those who completed longer missions of at least six months, and that less than three years may not provide enough time for the ventricles to fully recover.

Ventricles are cavities in the brain filled with cerebrospinal fluid, which provides protection, nourishment and waste removal to the brain. Mechanisms in the human body effectively distribute fluids throughout the body, but in the absence of gravity, the fluid shifts upward, pushing the brain higher within the skull and causing the ventricles to expand.

“We found that the more time people spent in space, the larger their ventricles became,” said Rachael Seidler, a professor of applied physiology and kinesiology at the University of Florida and an author of the study. “Many astronauts travel to space more than one time, and our study shows it takes about three years between flights for the ventricles to fully recover.”

You can read the paper here. The expansion of ventricles is a normal process due to aging, but I could not find any description in the paper noting its impact, for good or ill. Long periods of weightlessness brings it about quickly, but only temporarily.

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Ice-filled fissure on Mars?

12:14 pm

Ice-filled fissure on Mars?
Click for original image.

Cool image time! The picture to the right, cropped, reduced, and sharpened to post here, was taken on February 15, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The science team labeled this a “Terrain Sample”, which suggests but doesn’t guarantee that it was to fill a gap in the camera’s schedule in order to maintain that camera’s proper temperature, and therefore was targeted at a relatively random but potentially interesting location.

What we see is a fissure canyon, about 250 to 300 feet deep with cliffs about 125 high, that appears surrounded and even filled with icelike features. Even the craters on the plateau above the canyon appear like they either impacted in ice, or have since been filled and eroded by that ice.

But is it ice?
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Scientists claim to identify cause of Sun’s fast solar wind

9:59 am

The uncertainty of science: Using data from the Parker Solar Probe, scientists now believe they have identified the cause of Sun’s fast solar wind that streams from the magnetic regions on the Sun that are dubbed coronal holes.

In a paper published June 7, 2023 in the journal Nature, a team of researchers used data from NASA’s Parker Solar Probe to explain how the solar wind is capable of surpassing speeds of 1 million miles per hour. They discovered that the energy released from the magnetic field near the sun’s surface is powerful enough to drive the fast solar wind, which is made up of ionized particles—called plasma—that flow outward from the sun.

The results depend a great deal on computer modeling, based on our presently limited understanding of magnetic field processes in environments like stars. It will need to be confirmed by more data from Parker as well as later probes.

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Webb’s first deep field infrared image reveals hundreds of very early galaxies

9:47 am

The uncertainty of science: Using the Webb Space Telescope to take a 32-day-long infrared exposure, scientists have obtained the deepest deep field picture of the universe’s earliest time period, within which they have found more than 700 galaxies, 717 to be exact.

The initial survey of these galaxies appear to reveal several facts.

About a sixth of early galaxies in the JADES sample are in the throes of star formation of a kind we don’t see in the nearby universe, Endsley explains, marked by extremely bright emission at certain wavelengths. “Stars within very early galaxies are forming in these super-compact clumps,” he adds, “forming hundreds, perhaps thousands of these very massive, young stars all at once, basically within the span of a couple millions of years.”

But they weren’t “on” all the time. The low fraction of galaxies with such emission suggests that individual clumps would suddenly light up with new stars and then rest for some time. This “bursty” mode of star formation could explain the unexpectedly bright galaxies announced by other astronomers — they were simply looking at the galaxies fired up with unexpectedly intense star formation.

However, while these findings explain too-bright galaxies, they don’t explain the too-massive galaxies, another early, albeit controversial find from JWST data. Endsley explains that even as hot, massive newborn stars light up their galaxy, they’re not necessarily associated with all that much mass. “We’re not really finding evidence of these over-massive objects within our JADES sample,” he states.

In other words, this data appears to contradict earlier data from Webb that other researchers said revealed galaxies that were too massive and developed to have formed that soon after the Big Bang.

All of this data remains somewhat uncertain, and is based on only tiny tidbits of information, gleaned from mere smudges of red-shifted infrared light. Much more research will be required, some not possible by Webb, before we have any solid answers, and even then there is going to be a lot of uncertainty.

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Distorted floor of a Martian crater

1:15 pm

Overview map

Distorted floor of a Martian crater
Click for original image.

Cool image time! The picture to the right, rotated, cropped, reduced, and sharpened to post here, was taken on February 18, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the science team labels “Mantle Layers in Southern Mid-Latitudes.”

I would be less vague. These strangely shaped features invoke the typical glacial features seen throughout the mid-latitudes of Mars. The knobs and outcrops suggest some underlying breakdown that the top layers of glacial material has covered. They also suggest some form of sublimation or erosion process to the glacier itself.

The white rectangle inside the inset on the overview map above marks this location, covering the floor of an unnamed 10-mile-wide crater in the cratered southern highlands at 41 degrees south. In this region all the craters show some evidence of this sublimation, all suggesting that there is a near-surface underlying ice layer that when exposed vanishes to leave depressions or hollows. Here however it appears that ice layer is mostly intact, the knobs and ridges indicating the shape of the bedrock and large breakdown below.

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