Tag: science

Webb takes infrared image of Supernova SN1987A

10:04 am

Annotated infrared image from Webb
Click for original image.

The Webb Space Telescope has taken its first infrared image of Supernova SN1987A, the closest supernova to Earth in five centuries at a distance of 168,000 light years away in the nearby Large Magellanic Cloud.

The annotated image to the right, cropped, reduced, and sharpened to post here, shows that supernova remnant as Webb sees it. Most of the structures identified here have been observed now for decades as the material from the explosion has been expanding outward. However,

While these structures have been observed to varying degrees
by NASA’s Hubble and Spitzer Space Telescopes and Chandra X-ray Observatory, the unparalleled sensitivity and spatial resolution of Webb revealed a new feature in this supernova remnant – small crescent-like structures. These crescents are thought to be a part of the outer layers of gas shot out from the supernova explosion. Their brightness may be an indication of limb brightening, an optical phenomenon that results from viewing the expanding material in three dimensions. In other words, our viewing angle makes it appear that there is more material in these two crescents than there actually may be. [emphasis mine]

I highlight that one word because it is unnecessary, and is only inserted to punch up Webb’s abilities for public relations purposes. Moreover, the rest of the text of the full press release at the link is even worse. It provides little information about the evolution of this supernova since its discovery more than three decades ago, but instead waxes poetic again and again about how wonderful Webb is.

Though Webb certainly has much higher resolution than the earlier infrared space telescope Spitzer and can do far more, this tendency of NASA press releases to use these superlatives only devalues Webb. The images themselves sell the telescope. No need to oversell it in the text.

Meanwhile, the significance of SN 1987A is not explained. Since the development of the telescope by Galileo in the early 1600s, there has been no supernova inside the Milky Way. SN 1987A has been the closest, so it has been photographed repeatedly in multiple wavelengths to track the evolution of the explosion’s ejecta. Webb now gives us a better look in the infrared, though in truth the small amount of new details is actually somewhat disappointing.

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Vikram takes movie of Pragyan rover as it roves

9:30 am

Pragyan as seen by Vikram
Click for movie.

Using one of Vikram’s lander cameras, engineers have produced a short movie of India’s Pragyan rover as it rotated to avoid a small crater about ten feet ahead.

The picture to the right is from that 16-second movie, near its end. It appears that the engineers operating Pragyan were unhappy with almost any route ahead from its present position, as they rotated Pragyan almost 360 degrees, and even attempted forward motion at one point and then resumed rotation.

It is not clear if any of the craters visible in this picture are the crater that caused the detour. The movie however does provide a sense of scale. Pragyan is small, but it is able to maneuver easily using its six wheels.

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Reviewing a book blacklisted by Amazon because it dared say things Amazon doesn’t like

1:35 pm

The Plague of Models, blacklisted by Amazon
The Plague of Models, blacklisted by Amazon

They’re coming for you next: Last week I posted an essay on the over-use and misuse of computer modeling in today’s scientific community, focused specifically on the unreliability of all climate models to successfully predict any actual climate trends.

One of the individuals who read my essay, Kenneth Green, immediately commented here on Behind the Black to note that he had just published a book on this very subject, entitled The Plague of Models: How Computer Modeling Corrupted Environmental, Health, and Safety Regulations, describing how the misuse of models has resulted in the proliferation of government regulations based not on actual data but on computer models that in many ways are nothing more than the opinions of the computer programs.

Green also noted that Amazon has refused to make his book available for sale, essentially banning it for no justifiable reason. As he explained to me in an email,

My publisher, who is a start-up small Canadian publisher specializing in public policy books, tried to upload The Plague of Models to Amazon, as he had previously done with half a dozen other books while working at previous institutions as in-house publisher.

This time, unlike his previous experiences, the book was taken down shortly after it was uploaded (and we know the upload process worked, since the book was available briefly for preview, so there was no technical issue with the manuscript file). The publisher got a form-letter email saying that the book had been taken down because it may have violated some (non-specific) Amazon Term of Service. When he sent a note back requesting clarification/appeal, he got another form letter, this one repeating that the book may have violated some term of service, and warning that any attempt to re-upload would get his entire account terminated.
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Buried ridges at the bottom of a Martian abyss

11:03 am

Buried ridges in a Martian abyss
Click for full image.

Today’s cool image could be labeled a “What the heck?!” photo, as the origin of its most distinct feature is utterly baffling. The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 18, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows what look like a collection of meandering ridges peeking out from a terrain covered by thick dust.

The scientists label this dust-covered ground, as well as the ripple dunes to the south in the full image, “sand sheets.” Without question, the ground here seems to resemble a Sahara-like terrain. It is utterly featureless, other than the few bedrock features that poke up out of that sand. In the full image some peaks stick out, but it the meandering ridges in this section that are most intriguing. They are reminiscent of rimstone dams in caves, but what formed them remains baffling, since cave rimstone dams are formed by the interaction of limestone and water, and there is absolutely no evidence of any near surface ice at this location in the dry equatorial regions of Mars.

All the ridges signify is a buried terrain formed in some inexplicable way.
» Read more

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Scientists believe they have recovered the first known interstellar meteorite

8:52 am

A scientific expedition in the Pacific off the coast of Papua New Guinea has found what it thinks are spherules from the first known interstellar meteorite that hit the Earth on January 8, 2014 and dubbed IM1. From their preprint paper [pdf]:

On 8 January 2014 US government satellite sensors detected three atmospheric detonations in rapid succession about 84 km north of Manus Island, outside the territorial waters of Papua New Guinea (20 km). Analysis of the trajectory suggested an interstellar origin of the causative object CNEOS 2014-01-08: an arrival velocity relative to Earth in excess of ∼ 45 km s−1, and a vector tracked back to outside the plane of the ecliptic. The object’s speed relative to the Local Standard of Rest of the Milky-Way galaxy, ∼ 60 km s−1, was higher than 95% of the stars in the Sun’s vicinity.

In 2022 the US Space Command issued a formal letter to NASA certifying a 99.999% likelihood that the object was interstellar in origin.

Using a “magnetic sled” that they dragged across the seafloor, the scientists collected about 700 spherules thought to come from the meteorite, of which 57 have been analyzed and found to have properties that confirm their interstellar origin. As they note in their paper, “The spherules with enrichment of beryllium (Be), lanthanum (La) and uranium (U), labeled “BeLaU”, appear to have an exotic composition different from other solar system materials.”

The “BeLaU” elemental abundance pattern does not match terrestrial alloys, fallout from nuclear explosions, magma ocean abundances of Earth, its Moon or Mars or other natural meteorites in the solar system. This supports the interstellar origin of IM1 independently of the measurement of its high speed, as reported in the CNEOS catalog and confirmed by the US Space Command.

Based on the sparse data, the scientists speculate that these spherules could have come from the crust of an exoplanet, the core collapse of a supernova, the merger of two neutron stars, and even possibly “an extraterrestrial technological origin.” They have no idea, but all these are among the possibilities.

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Pragyan snaps first pictures of Vikram sitting on the Moon

8:28 am

Vikram as seen by Pragyan
Click for original image.

India’s space agency ISRO has released the first two pictures from the Pragyan rover showing the Vikram lander that bought both to the Moon safely.

The picture to the right is the close-up image, which shows two of Vikram’s science instruments. CHASTE is a probe that has been measuring the temperature of the Moon’s regolith at this spot, while ILSA is a seismometer for measuring the seismicity around the landing site.

Both spacecraft have been on the lunar surface now for one week, which means they are both halfway through their nominal two-week mission that lasts until lunar sunset, occurring on September 4th. Neither were designed to survive the 14-day-long lunar night, though engineers will attempt to kept both alive.

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Update on the ongoing research of the closest supernovae in a decade

12:47 pm

Gemini North image of supernova in Pinwheel Galaxy
Click for original image, taken by the Gemini North telescope in Hawaii.

Link here. Though the press release from UC-Berkeley focuses mostly of research being done by its astronomers, it also provides a very good overview of what all astronomers worldwide have been learning since Supernova SN 2023ixf was first discovered by amateur astronomer Koichi Itagaki in Japan on May 19, 2023 in the Pinwheel Galaxy, only 20 million light years away. This tidbit is probably the most significant:

Another group of astronomers led by Ryan Chornock, a UC Berkeley adjunct associate professor of astronomy, gathered spectroscopic data using the same telescope at Lick Observatory. Graduate student Wynn Jacobson-Galán and professor Raffaella Margutti analyzed the data to reconstruct the pre- and post-explosion history of the star, and found evidence that it had shed gas for the previous three to six years before collapsing and exploding. The amount of gas shed or ejected before the explosion could have been 5% of its total mass — enough to create a dense cloud of material through which the supernova ejecta had to plow.

Such data is going to help astronomers better predict when a star is about to go boom, by identifying similar behavior.

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The prevailing winds in Mars’ volcano country

12:35 pm

The prevailing winds in Mars' volcano country
Click for original image.

Today’s cool image is actual one new picture and four past images, which taken together reveal something about the larger wind patterns on Mars. The picture to the right, cropped, reduced, and sharpened to post here, was taken on June 27, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and shows a tiny wind-swept section of the giant volcanic ash field dubbed the Medusae Fossae Formation, about the size of the subcontinent of India and thought to be source of most of the dust on Mars.

The innumerable parallel thin ridges here all suggest that the prevailing winds blow from the southeast to the northwest. As they blow, the scour the surface ash out, and sometimes reveal the underlying bedrock, which here shows up as those small peaks and a handful of northeast-to-southwest trending larger ridges. Note too that the picture shown is only a small section of the full image, which shows that this landscape continues for a considerable distance in all directions.
» Read more

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InSight team releases a global map of Mars’ seismic zones

10:03 am

Global map of quakes on Mars
Click for original image.

In a new paper that reviewed the entire archive of Mars quakes detected by the seismometer on InSight during its four years of operation on the Martian surface from 2018 to 2022, scientists have now released an updated global map showing the regions on Mars where seismic activity is most common. From the abstract:

Seismicity on Mars occurs mostly along or north of the boundary between the southern highlands and northern lowlands. Valles Marineris is seismically more active than previous catalogs of located events imply. Further, we show evidence that two events likely originate from the Olympus Mons region.

The map to the right is figure 6 from the paper, and shows clearly the sum total of InSight’s data. The yellow triangle marks InSight’s landing spot. The red line delineates the distant quakes from the nearby quakes detected by InSight. The green line is what the scientists identify as the border between the northern lowland plains and the southern cratered highlands. The data suggests that transition point could be linked geologically in some manner to the quakes themselves.

Though the majority of the detected quakes were in the Cerberus Fossae region, the data also suggests two other seismic active regions, one under the giant canyon Valles Marineris and the other south of Mars’ largest volcano, Olympus Mons.

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Residue ice in southern mid-latitude Martian crater?

11:16 am

Residue ice in the southern mid-latitudes of 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 10, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows an unnamed 1.2-mile-wide crater at about 35 degrees south latitude with what appears to be residual glacial ice hugging its north interior wall.

As this is in the southern hemisphere, the ground immediately below the south-facing interior wall of the crater is going to be in shadow the most, and thus it will also be the place where any surface or near-surface ice will survive the longest. In this case it appears that from the bumpy nature of that residual ice it has also been sublimating away. Within it however remains the faint hint of multiple layers, suggesting about a dozen past climate cycles with each new cycle producing a new but smaller layer with less ice.

The material in the southern half of the crater floor appears to be dust formed into ripple dunes.
» Read more

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JAXA scrubs launch of X-Ray telescope & SLIM lunar lander due to high winds

8:57 am

SLIM's landing zone
Click for interactive map.

Because of high winds, Japan’s space agency JAXA yesterday scrubbed the last launch of its H2A rocket, carrying the XRISM X-Ray telescope and the SLIM lunar lander.

A nice description of both payloads can be found here. XRISM is a simplified reflight of the Hitomi X-Ray telescope that failed immediately after launch in 2016.

Though SLIM carries a camera and two secondary payloads, both designed to hop along on the surface and obtain some data, its main mission is engineering, testing whether a robotic spacecraft can achieve a precision landing with a target zone of 100 meters, or 310 feet. The map to the right shows SLIM’s landing site, with the white dot in the close-up inset a rough approximation of that entire target zone. If successful this technology will make it possible to put unmanned planetary probes in places previously thought too dangerous or rough.

All three craft are designed to operate for only about fourteen days, during the daylight hours of the 28-Earth-day-long lunar day.

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Flow channels on Mars

11:13 am

Flow channels 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 May 13, 2023 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows what the scientists call a “channel and depression”, though to my eye everything looks like flow channels, descending to the east.

The drop from the narrow northern channel to wider southern channel is about 200 feet, with the small crater on the left sitting about halfway between. To our Earthbound eyes, something clearly flowed downhill from that northern channel into the wider channel. What we don’t know now is what the material was that did the flowing?

Was it liquid water? Glaciers? The overview map below provides some context, though it doesn’t actually provide an answer.
» Read more

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