New evidence suggests the Earth’s inner core no longer rotates faster than the planet’s outer layers

The uncertainty of science: The same scientists who in the late 1990s thought they had detected evidence that the Earth’s inner core rotates faster than the planet’s mantle now say that this faster rotation ceased sometime around 2009.

In 1996, Song and another researcher reported studying earthquakes that originated in the same region over three decades, and whose energy was detected by the same monitoring station thousands of kilometres away. Since the 1960s, the scientists said, the travel time of seismic waves emanating from those earthquakes had changed, indicating that the inner core rotates faster than the planet’s mantle, the layer just beyond the outer core.

…Now, Yang and Song say that the inner core has halted its spin relative to the mantle. They studied earthquakes mostly from between 1995 and 2021, and found that the inner core’s super-rotation had stopped around 2009. They observed the change at various points around the globe, which the researchers say confirms it is a true planet-wide phenomenon related to core rotation, and not just a local change on the inner core’s surface.

It is important to note that there has not been a consensus on this data, that some scientists even doubt the super-rotation ever existed. The data itself is sparse enough and includes enough gaps to allow for this disagreement, which also means this new conclusion is also uncertain.

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Communications issue shuts down one of Webb’s instruments

The near infrared instrument on the Webb Space Telescope, NIRISS, has been unavailable for science observations for more than a week due to a communications issue.

On Sunday, Jan. 15, the James Webb Space Telescope’s Near Infrared Imager and Slitless Spectrograph (NIRISS) experienced a communications delay within the instrument, causing its flight software to time out. The instrument is currently unavailable for science observations while NASA and the Canadian Space Agency (CSA) work together to determine and correct the root cause of the delay.

According to the update, the instrument’s hardware, as well as the rest of the telescope, has been unaffected and remains in good condition.

In November the telescope’s mid-infrared instrument MIRI experienced its own problems with one of its “grating wheels” that allows it to some spectroscopy. Since then the instrument has been in use, but it is unclear if the issue was resolved or observations have had to be adjusted to avoid the problem.

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January 23, 2023 Quick space links

Courtesy of BtB’s stringer Jay.

 

 

 

  • 2022 was a profitable year for space insurance companies, the third in a row
  • Jay notes this interesting detail from article: “Many LEO operators including SpaceX are choosing to forgo insuring satellites, not least because the size of their constellations gives them built-in redundancy. The estimated lifetimes of satellites in LEO are also far shorter than their cousins in GEO.”

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Today’s blacklisted American: Game publisher fires employee for expressing conservative opinions

Limited Run Games: opposed to free speech

They’re coming for you next: The game publisher Limited Run Games recently fired its community manager Kara Lynne (also known by her married name, Kara Gooch) because one anonymous person complained to the company that she had expressed some conservative opinions on her personal account on Twitter.

Twitter user Purple Tinker (who has since deleted their account) described Lynne as “a transphobe” with several known right-wing and transphobic accounts on the list of accounts she follows on Twitter, including Ben Shapiro, Libs of TikTok, and others.

Purple Tinker pointed to several tweets made by Lynne in the past, including one in which she says “if you think the # of trans crying about using a bathroom is higher than the perves [sic] using the excuse, you are what is wrong with this world”. Lynne has since made her Twitter account private, so it’s not possible to see any of the tweets she made.

Apparently, Lynne had expressed enthusiasm in an earlier tweet about the game Hogwarts Legacy, based on J.K. Rowling’s Harry Potter books, and since Rowling is now being blacklisted by the left and its allies in the queer movement because she thinks rationally that you can’t become a woman merely because you say so, Purple Tinker decided Lynne had to also be investigated and destroyed for defying that blacklist.

You can read Lynne’s detailed full response to her firing here. Her account of her firing tells us a lot about the weak character of the management of her former employer.
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Martian crater with mound of ice? mud? hardened sand?

Crater with mound
Click for full image.

Cool image time! The photo to the right, cropped to post here, was taken on October 31, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a small 4,000-foot-wide crater that is practically filled with a smooth, almost perfectly spherical mound, with the rest of the crater interior filled with sand dunes and what appears to be glacial debris.

Is that mound also glacial debris, covered with a layer of dirt and dust to protect it? If so, one wonders how the ice ended up in this shape. There are other craters with similar mounds in this region, all suggesting glacial debris but with the same question. Craters with lots of near surface ice in this region more often have a squishy blobby look.

Is the mound instead possibly mud, expressing the existence of a mud/ice volcano? If so, it shows no central pit or caldera, which is typical of such things.

Is it hardened sand? Martian dust that gets blown into craters generally gets trapped there, building up over time. If so, however, why does it have a smooth almost perfectly rounded shape? The ripple sand dunes surrounding it are more like what you would expect.

The small craters on the mound also tell us that it is hardened and old, no matter what it is made of.
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Animation of Jupiter’s clouds

Cool video time! Using a photo taken by Juno during its 2018 fly-by of Jupiter, citizen scientist Thomas Thomopoulos has created a short animation showing the flow of Jupiter’s clouds. He also added some 3D relief by assigning elevation to the image’s greyscale, with lighter regions assigned higher altitudes.

I have embedded the animation below. Run it at the slowest speed for the best effect. It is quite spectacular, though it is also important to note that it is not reality. Thomopoulos is simply giving us a hint of the natural evolution of the cloud structures, both in elevation and in time.

You can see another equally impressive animation by Thomopoulos here of several of Jupiter’s polar storms, using AI technology to smooth out the loop.
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First Vulcan rocket arrives at Cape Canaveral

ULA’s first Vulcan rocket has now arrived at Cape Canaveral in preparation for its planned inaugural launch before the end of March.

This first mission for Vucan will fly in a VC2S configuration. “VC” stands for “Vulcan Centaur.” The number, in this case “2,” represents the number of solid rocket boosters needed and the final letter stands for the payload fairing length.

VC2S will use a 51-foot-long Standard payload fairing. Nestled inside will be a few different payloads. This mission will send the first two Kuiper prototype satellites into Low Earth Orbit (LEO), Astrobotic’s Peregrine lunar lander to the Moon and a Celestis Memorial Spaceflight payload into deep space. The remains of several people connected to the original Star Trek series will be launched on what Celestis dubbed the “Enterprise Flight,” including show creator Gene Roddenberry along with actors Nichelle Nichols and Jackson DeForest Kelley.

This first Vulcan launch will also be the first of two flights required by the Pentagon in order to certify Vulcan for military launches. Since ULA already has contracts for seven Vulcan military launches, it very much wants to get these two launches off this year, as soon as possible. According to the article at the link, ULA is thus aiming to fly this year those two test flights, followed quickly by the first military launch.

Whether it can complete three Vulcan launches in 2023 is quite uncertain. For example, it will need to get four more BE-4 engines from Blue Origin for the second and third launches, and there is no indication at this time that Blue Origin is close to delivering.

Then there is the delays and risks involved with this first launch. Though ULA has decades of experience building and launching rockets, the first launch of a rocket almost always experiences delays during testing. We should expect the same with Vulcan.

Assuming this schedule holds, however, this means ULA is targeting 10 launches in 2023, five Atlas-5 launches, two Delta Heavy launches, and three Vulcan launches. That would be the most launches by this company in a year since 2016.

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First launch from Shetland Islands predicted for the fall

According to an official at the SaxaVord spaceport in the Shetland Islands in Scotland, its first orbital satellite launch is now expected before the end of this year.

Scott Hammond, director of operations at SaxaVord spaceport, acknowledged there is often uncertainty around timetables for private space launches. However, he said a recent agreement with a German company, Rocket Factory Augsburg, would see them begin testing their engines in the summer ahead of a launch later in the year.

He told the Press Association: “Probably in July, we’re going to start full stage testing. That will be the full, first stage, nine engines all firing for about three minutes. So that’ll be really, really impressive. I expect about four months or so of that depending on success. And then we’re looking with Rocket Factory to launch towards the end of the year, for the orbital launch.”

I would not bet a lot of money on this schedule. Rocket Factory is a German rocket startup that has never launched before, and the first launch from such startups are routinely delayed months to years. What Hammond is really doing is creating buzz for SaxaVord, even as a rival spaceport in Sutherland, Scotland, is getting built.

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January 20, 2023 Quick space links

Courtesy of BtB’s stringer Jay.

 

 

 

 

 

 

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The youngest flood lava on Mars, flowing past a crater

Crater with lava flow
Click for full image.

Cool image time! The photo to the right, rotated, cropped, reduced to post here, was taken on December 3, 2022 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The title given to this image by the MRO science team is “Upstream Edge of Crater in Athabasca Valles.” The crater itself is a pedestal crater, uplifted from the surrounding terrain because it was more resistant to erosion.

The material to the east of the crater’s rim definitely appears to have flow characteristics, but is it wet mud, glacial ice, or lava?

To figure this out we need as always some context. The latitude, 8 degrees north, immediately eliminates mud or glacial material. This location is in the dry equatorial regions of Mars, where no near surface ice has yet been found. Thus, the flow features are likely hardened lava.

What direction however was the flow? Was it flowing to the north, widening as it moved past the pedestal crater? Or was it to the south, narrowing as it pushed past that crater? To answer this question we need to widen our view.
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