Category: Behind The Black

The Navy’s overreaction to COVID-19

12:09 pm

On October 10th the press breathlessly reported that “nearly two-thirds of the Navy’s deployable warships have endured COVID-19 outbreaks”.

What was not mentioned was the number of sailors killed by the outbreaks. Though the NAVY report says nothing about mortality, it does say this:

Sailor rates of infection are generally the same as the rates of infection in the local area. … Within the uniformed Navy population, roughly 35 percent of infected sailors exhibit few to no symptoms. This should build confidence in the ship’s ability to fight through outbreaks.

I strongly suspect that practically no one has died yet from coronavirus on a Navy ship. In fact, this sounds exactly like a typical flu season, where the flu quickly spreads among those confined in close quarters, but then peters out shortly thereafter, forgotten.

In other words, COVID-19 in the Navy (as elsewhere) is really nothing more than a variation of the flu, possibly more infectious to all and more harmful to the elderly sick, but harmless to practically everyone else.

The bad part of this is that, rather than let the disease play out quickly so that crews are promptly immune and the epidemic no longer can effect efficiency — as humanity has done for eons — the Navy is panicking like everyone else, instituting strict quarantines on all those infected, plus social distancing and mask rules. All this will do is prolong the agony, and interfere with the Navy’s operation. You can’t run a ship or a submarine realistically if you require everyone to keep six feet distance at all time.

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NASA charging Estee Lauder $17,500 per hour for filming its perfume on ISS

11:00 am

Capitalism in space: It now appears that NASA is charging Estee Lauder $17,500 per hour for filming the perfume that was just brought to ISS on the most recent Cygnus freighter.

The cosmetics giant will pay $17,500 per hour for the astronauts to take photos of their serum in space. Coincidentally — or not — the Space Station orbits the earth at 17,500 miles per hour.

The International Space Station is an orbiting laboratory for scientific research, but it’s the photo ops and viral videos that capture the public’s imagination.

Estée Lauder will get video and photos of their out-of-this-world product in the most photographed spot on the space station — the Cupola. The photos are not to be used in print or television advertising, but instead on social media, according to NASA. The astronauts won’t be using the product or be featured in the pictures.

The article also notes that NASA is dedicating 5% of astronaut time to commercial activities. Sooner or later I think NASA is also going to have to start paying their astronauts for this work. They deserve their share of the proceeds.

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A lunar landslide

10:03 am

Landslide on the Moon
Click for full image.

Cool image time! The image to the right was posted by the Lunar Reconnaissance Orbiter (LRO) science team on October 9, 2020, and shows a spectacular landslide almost a mile and a half long that had occurred on the interior rim of a crater on the Moon.

The top of the rim is on the left, with the landslide breaking out onto the floor of the crater on the right.

The walls of Kepler crater (30 kilometer diameter) exhibit numerous landslides. In this example, a landslide of dark material begins about 100 meters below the rim from a narrow box canyon. The box canyon is about 50 meters wide and 300 meters long. Overall, the slide is extends some 2300 meters (from the end of the canyon to its base). The base of the slide is on a fault block that lies some 1800 meters below the rim. The wall slope is about 33 degrees.

This slide is actually composed of a series of narrow landslides 20-30 meters wide. Along most of the slope, the individual slides overrun each other forming a band of debris up to about 180 meters wide. At the base of the slope, the individual slides can be recognized as they move apart forming a fan of material. A few individual isolated slides also occur adjacent to the main mass. The overlapping nature of these small slides indicate that the overall feature may have formed over a period of time, rather than all at once.

From above and at this resolution, the landslide looks almost like frozen flowing liquid. It allso looks like it began with a scattering of boulders breaking free at the top all at once that quickly consolidated into a single massive avalanche.

At the link you can zoom in or out to look at the entire image, at full resolution.

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SpaceX begins installing Raptor engines on Starship prototype #8

9:47 am

Capitalism in space: With Starship prototype having successfully passed its tank tests SpaceX has begun installing three Raptor engines in preparation for static fire tests followed by a 50,000 foot high hop.

Once the Raptors are installed, Starship SN8 is expected to undergo an extensive test program, opening with fueling tests, a spin prime test, and preburner tests, before the first Static Fire test.

That opening Static Fire test will be the first time three Raptors have been fired up simultaneously.

Once that opening Static Fire test has been completed, a data review will be conducted on engine performance and related systems – such as the Ground Support Equipment (GSE) – which will allow the nosecone to be installed on to SN8 at the launch site.

At that point the prototype will be ready for its hop. Based on the pace SpaceX is setting (and assuming all goes well), this flight should occur sometime in the next month, possibly at almost the same time as the next manned Dragon flight to ISS.

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A mile-long trail of human footprints about 12,000 years old

9:41 am

Scientists have found in New Mexico a mile-long trail of human footprints from about 12,000 years ago that was probably left by a woman and toddler.

Even more interesting, the tracks show that the woman (or male adolescent) retraced her route, without the child.

Unlike many other known footprint trackways, this one is remarkable for its length – over at least 1.5km [almost a mile] – and straightness. This individual did not deviate from their course. But what is even more remarkable is that they followed their own trackway home again a few hours later.

Each track tells a story: a slip here, a stretch there to avoid a puddle. The ground was wet and slick with mud and they were walking at speed, which would have been exhausting. We estimate that they were walking at over 1.7 metres per second – a comfortable walking speed is about 1.2 to 1.5 metres per second on a flat dry surface. The tracks are quite small and were most likely made by a woman, or possibly an adolescent male.

At several places on the outward journey there are a series of small child tracks, made as the carrier set a child down perhaps to adjust them from hip to hip, or for a moment of rest. Judging by the size of the child tracks, they were made by a toddler maybe around two years old or slightly younger. The child was carried outward, but not on the return.

There is also evidence of a mammoth and sloth crossed the tracks in-between the outward and return journey, with the sloth apparently sensing the human tracks or presence.

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Zvezda both leaking and heating up

9:23 am

A Russian news source today reported that the temperature in the ISS module Zvezda has been increasing even as air has been leaking slowly from it.

The article provides little additional detail, other than saying that “normal temperature should be restored” by today.

Why the module should be warming as it slowly leaks air is puzzling. Either way, as this is a module that has been in space for twenty years and is also a key component in the station’s operations, locating the leak is crucial. It might simply be caused by a micrometeorite hit, which can be easily patched. Or it could be caused by something more fundamental, caused by the module’s age, and thus more difficult, possibly even impossible, to fix. If so, the sooner engineers know the better.

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China’s Long March 3B launches another remote sensing satellite

11:47 pm

China today (October 11) successfully used its Long March 3B rocket to place another remote sensing satelle into orbit.

No word on whether the first stage and its strap-on boosters landed on any homes, or if they were equipped with fins to guide their re-entry.

The leaders in the 2020 launch race:

26 China
16 SpaceX
10 Russia
4 ULA
4 Europe (Arianespace)

With this launch China moves back into a tie with the U.S., 26-26, in the national rankings.

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Next manned Dragon launch delayed

11:54 pm

Because of an engine issue that caused Falcon 9 launch of a military GPS satellite to abort at T-2 seconds on October 2nd, SpaceX and NASA have decided to delay the next manned Dragon launch from October 31st “to early-to-mid November.”

The one to two week delay will give the company time to analyze the issue involving an “unexpected pressure rise in the turbomachinery gas generator” that are used to drive the rocket’s Merlin engine turbopumps.

It seems unlikely that this problem is systemic to all Merlin engines, considering the number of rocket launches SpaceX has successfully completed in the last four years. Each launch has used ten engines, with no evidence of this problem appearing previously.

At the same time, no one wants a problem on a manned flight. Better to completely understand why it happened on the GPS launch first before launching four astronauts on the rocket.

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On the radio

3:19 pm

This Sunday, October 11, 2020, from 6:00-8:00 pm (Eastern) I will be on the Task Force Gryphon radio show on Kgra Radio.

The broadcast will be live and they will be taking calls and chat questions. Feel free to call or text in. The conversation should be lively, as the host, who goes by the nom de plume of Commander Cobra, is knowledgeable, an aviation guy, and also a big fan of Behind the Black.

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More Martian pits!

2:28 pm

Pit #1
Click for full image.

Pit #2
Click for full image.

Though the number of new pictures showing pits and possible caves from the high resolution camera on Mars Reconnaissance Orbiter (MRO) has significantly tailed off in the past year, as I noted in my previous post on Martian pits in September, the pictures are still rolling in. This post will highlight five new photos and the pits therein.

The first two, on the right, are both located on the southern flanks of the giant volcano Arsia Mons, where many such pits are found. They were taken respectively on August 16, 2020 and August 27, 2020. The first was a captioned image from MRO’s science team:

In this image, the ceiling of the lava tube collapsed in one spot and made this pit crater. The pit is about 50 meters (150 feet) across, so it’s likely that the underground tube is also at least this big (much bigger than similar caves on the Earth). HiRISE can’t see inside these steep pits because it’s always late afternoon when we pass overhead and the inside is shadowed at that time of day.

What I find most interesting about both images is that the skylights do not occur where you’d expect. In image #1, the meandering rill that suggests an underground lava tube is about 1,000 feet south of the pit. The pit itself seems unrelated to that rill. In image #2, the surface shows no obvious evidence of an underground tube matching the three aligned pits. There is the hint of a narrow depression along the alignment of the three pits, but this could just as easily be evidence of wind-blown dust along that alignment.

In the full image all three pits appear to sit inside a very wide and very shallow northwest-to-southwest depression, but this is hardly certain, and regardless the three pits align in a different direction.

The overview map below provides some context.
» Read more

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Flying over Jupiter

11:02 am

Cool movie time! Using images produced by Juno in orbit around Jupiter, citizen scientist Kevin Gill has produced a very nice movie of the spacecraft’s 27th fly-by on June 2, 2020.

During the closest approach of this pass, the Juno spacecraft came within approximately 2,100 miles (3,400 kilometers) of Jupiter’s cloud tops. At that point, Jupiter’s powerful gravity accelerated the spacecraft to tremendous speed — about 130,000 mph (209,000 kilometers per hour) relative to the planet.

I have embedded the movie below the fold. The choice of a piece of music by Vangellis might seem hokey, but I think in this case it works very nicely. I also was impressed with the addition of some 3D depth near the movie’s beginning.
» Read more

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More results about Bennu from OSIRIS-REx

10:21 am

Scientists using the OSIRIS-REx spacecraft have now published a special collection of papers outlining some of their discoveries made during that spacecraft’s observations of the asteroid Bennu from February to October 2019.

These papers just make official much of what was revealed during a conference I attended in November 2019. To sum up the papers:

  • Bennu has a lot of carbonates across its surface.
  • Some of that material came from another object that had to have had water.
  • The asteroid’s boulders come in two types, dark-porous and bright-solid, with the latter likely from that water-bearing other asteroid
  • Bennu’s surface is fresh, only recently exposed to space, including the sample site Nightingale.
  • Bennu’s interior has large voids, and its equatorial region is less dense.

The discovery of carbonates, produced from the interaction of water and carbon dioxide, is a big deal. As Dante Lauretta, OSIRIS-REx principal investigator, explained at that November conference, “To me this is one of the most exciting results from the conference.”

These findings have allowed scientists to theorize that Bennu’s parent asteroid likely had an extensive hydrothermal system, where water interacted with and altered the rock on Bennu’s parent body. Although the parent body was destroyed long ago, we’re seeing evidence of what that watery asteroid once looked like here – in its remaining fragments that make up Bennu. Some of these carbonate veins in Bennu’s boulders measure up to a few feet long and several inches thick, validating that an asteroid-scale hydrothermal system of water was present on Bennu’s parent body.

The material could not have been created on Bennu itself, which means it formed on a different object that was large enough and existed long enough to create the veins in these boulders. That material was then flung back into space to settle onto Bennu’s surface.

The freshness of Bennu’s surface is also a big deal, as it means that etither the asteroid is not that old, or that its surface somehow gets plowed over periodically. It also means that when OSIRIS-REx grabs samples at the Nightingale site on October 20th, they will be grabbing material that has not been altered much by the harsh environment of space.

Finally, the data about Bennu’s interior and density is maybe the neatest discovery. As the press release notes,

The reconstructed gravity field shows that the interior of Bennu is not uniform. Instead, there are pockets of higher and lower density material inside the asteroid. It’s as if there is a void at its center, within which you could fit a couple of football fields. In addition, the bulge at Bennu’s equator is under-dense, suggesting that Bennu’s rotation is lofting this material.

Bennu’s very weak gravity makes it a very alien and hard-to-comprehend place. It appears that the gravel in this floating gravel pile is barely held together, some interlocking in a way that leaves many open gaps, with other pieces pulled outward by the spin of the asteroid.

In reading these results, my first impression was an overwhelming sense of time and its inconceivable vastness. Much of Bennu’s most primitive material comes from the early solar system, about six billion years ago. Other material is newer, but required many many millions of years to get created elsewhere, and then somehow end up in space to be captured by this asteroid.

A million years is a very long time. A billion years is a thousand times longer. To conceive such time frames and all that can happen during that time is practically impossible. Bennu has shown us just a hint of how much can happen, some of which we would never have imagined otherwise.

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Branson picks West Virginia to build test hyperloop underground train

9:35 am

Another Branson scam? Richard Branson’s new big venture to build a hyperloop magnetic underground train to transport cargo and people, dubbed Virgin Hyperloop, has chosen West Virginia as the location to build its first test prototype.

Virgin Hyperloop has picked the U.S. state of West Virginia to host a $500 million certification center and test track for billionaire Richard Branson’s super high-speed travel system, the company told Reuters. The center will be the first U.S. regulatory proving ground for a hyperloop system designed to whisk floating pods packed with passengers and cargo through vacuum tubes at 600 miles (966 kmph) an hour or faster.

Later, Branson announced the decision in a press conference on Thursday, joined virtually by U.S. Transportation Department Secretary Elaine Chao, the state’s Republican governor Jim Justice, and U.S. Senators from West Virginia Shelley Moore Capito, a Republican, and Joe Manchin, a Democrat.

…Construction is slated to begin in 2022 on the site of a former coal mine in Tucker and Grant Counties, West Virginia, with safety certification by 2025 and commercial operations by 2030, the company said.

Forgive me if I think is this nothing but a Branson con-job of the taxpayers and his investors. For example, though the company has raised $400 million of investment capital, much of that came from UAE investors. Considering that Branson took other Arab investors for half a billion on his Virgin Galactic scam, which after fifteen years has never flown an operational flight and will likely never make a dime of profit, I find this investment from the UAE astonishing.

Though the article doesn’t state where the remaining $100 million of cash came from, I suspect it is taxpayer money, from both federal and state coffers.

I am very dubious any of this will ever happen. A decade hence I expect the system will still be in development, with Branson calling for more tax dollars and new investors. Maybe by then he’ll do what he did with Virgin Galactic, go public and he sell his stock for a big profit, leaving others holding the bag.

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Starship prototype #8 passes tank tests; engine installation next

9:15 am

Capitalism in space: SpaceX’s eighth Starship prototype has passed its tank, thruster, and even fin tests, setting it up for the installation of its three Raptor engines.

Once installed, they will perform several static fire tests, on the launchpad. If those tests are successful, the company will then proceed with a full 50,000 foot test flight. Based on the pace of operations, my guess is that this hop will occur in about two to four weeks.

I’ve embedded one of the videos at the link below the fold, showing a variety of activity at the site.

In other SpaceX news, the Tesla that was put in solar orbit on the first Falcon Heavy test launch has just made its first “fly-by” of Mars, getting to within 5 million miles of the red planet. At that distance the planet really isn’t very close, which is why I put the word fly-by in quotes. That Tesla’s future:

The Roadster will eventually barrel into either Venus or Earth, likely within the next few tens of millions of years, a 2018 orbit-modeling study determined . But the chances of an Earth or Venus impact in the next million years are just 6% and 2.5%, respectively.

» Read more

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Yodeling!

6:04 pm

An evening pause: Hat tip Jim Mallamace, who writes,

If I understood German, I think I would enjoy this performance even more. Angela Wiedl is Bavarian, Melanie Oesch is Swiss, and Herlinde Lindner is Austrian. From what I read in the comments, each singer sings the “Erzherzog Johann Jodler” in her own country’s version of German.

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Boom unveils its first half-scale prototype commercial supersonic jet

1:48 pm

Boom Supersonic, an aviation company that wants to build commercial supersonic passenger jets, has unveiled its first half-scale prototype, dubbed the XB-1, or “Baby Boom”.

They had announced the development of this jet several years ago, and have experienced some delays since. They had hoped to begin commercial operations of their commercial model, dubbed Overture, by ’23, but this remains unclear. Regardless, there does seem interest in this airplane among the commercial carriers, assuming they survive the Wuhan flu panic.

Boom says that the airliner has a projected unit cost of around $200 million each, not including a customer’s desired interior configuration and other unspecified optional extras. This would make it cheaper than many subsonic widebody airliners now on the market, but those aircraft can also carry substantial more passengers. For example, in 2018, Airbus said that the average price of one of its popular A330-200s was approximately $238.5 million, but that aircraft has a maximum seating capacity of 406, nearly four times that of Overture as presently planned. Boeing says that the average price of one of its 767-300ER airliners is around $217.9 million, but again, those planes can seat nearly 300 passengers, depending on the internal configuration.

There has already been not insubstantial interest in the Overture, though, with Boom saying it has commitments to buy up to 76 of the jets from five airlines, including Virgin and Japan Airlines (JAL). Virgin Group has been a major investor in Boom for years now, as well. The Spaceship Company, a Virgin Galactic subsidiary, was previously reported to be preparing to assist in building and testing the airliners.

I will admit, however, that I do not find it encouraging that Virgin Galactic is involved in the plane’s development. In fact, it might even help explain why development was delayed.

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The idiocy, ignorance, and corruption of California’s Governor Newsom

12:44 pm

In the past week the Democratic governor of California, Gavin Newsom, has demonstrated that in his quest to cement the dictatorial powers he gave to himself with the arrival of the Wuhan virus, he really has no interest in any facts or real scientific data.

First, he announced with great fanfare on October 5th that the country and his state were entering a new terrible outbreak of COVID-19. “This is the second wave,” he declared grimly, adding,

“We continue to have a lot to do on COVID-19 transmission,” he said. “You’re starting to see an increase in COVID cases across the country,” the governor observed. “You’re seeing this not just across the country, you’re seeing this across the world.” Newsom then reported that 21 states across the U.S. are seeing increases.

Newsom then made reference to the Spanish flu pandemic that hit America in 1918, noting that “the second wave in 1918 was the most deadly.”

The problem for Newsom however are the facts, as shown in the graph below.
» Read more

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World’s longest pedestrian suspension bridge to open in ’21

9:52 am

A new tourist attraction, the world’s longest pedestrian suspension bridge, is set to open in Portugal next year.

At this length, the new bridge will be considered the longest pedestrian suspension bridge in the world, beating out the Charles Kuonen Suspension Bridge in Switzerland, which spans 1,621 feet and opened in 2017, according to The Sun. But it isn’t just long, it’s also situated 575 feet above the ground, connecting the Aguieiras Waterfall and Paiva Gorge.

I have embedded below the fold a video showing the bridge under construction. As the article notes, if you are afraid of heights this is not the tourist attraction for you.
» Read more

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Musk: Starlink about to roll out commercial service

9:37 am

Capitalism in space: With the launch earlier this week of another 60 Starlink satellites, Elon Musk has revealed that they now have enough satellites in orbit to soon begin commercial operations.

After yesterday’s launch of 60 Starlink satellites, SpaceX CEO Elon Musk wrote on Twitter that “[o]nce these satellites reach their target position, we will be able to roll out a fairly wide public beta in northern US & hopefully southern Canada. Other countries to follow as soon as we receive regulatory approval.”

Musk did not say when the satellites will reach their target position. SpaceX has over 700 satellites in orbit after yesterday’s launch.

It will like take a few months to get these satellites into position. Regardless, the speed at which SpaceX operates once again has put them ahead of their competitors. OneWeb, the only other similar constellation with satellites in orbit, was once far ahead of SpaceX but has been stalled as it recovers from bankruptcy. Amazon’s Kuiper satellite constellation is so far only a proposal, and like most everything else the company said it would build, has moved forward with the speed of a glacier.

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Momentus to go public

9:29 am

Capitalism in space: Momentus, an company focused on providing tugboat services in orbit, will become a publicly traded stock in conjunction with its merger with another investment company.

In recent months, Momentus has expanded its staff and business line to include hosting payloads and capturing satellites already in orbit with a robotic arm the firm is developing with Made In Space Europe, a Redwire subsidiary.

Through the merger and public offering, Momentus hopes to obtain capital to speed up development of its family of space tugs. In addition to Vigoride, Momentus is developing Ardoride, a vehicle to move small and medium-size satellites to custom orbits, and Fevoride, a vehicle to move “dozens of tons of cargo anywhere in outer space,” according to the Momentus website.

With this deal I think there will be two new space companies traded publicly, Momentus and Virgin Galactic. Unlike Virgin Galactic, whose stock is based on smoke and mirrors, Momentus is actually providing a commercial product that fills a need in space, and sounds like a good investment.

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Starliner Commander steps down from first manned mission

9:19 am

Capitalism in space: Boeing’s company astronaut chosen to command the first manned mission of its Starliner capsule has stepped down because the flight would prevent him from attending his daughter’s wedding next year.

In a video posted to his Twitter account, Ferguson said it was a difficult decision, but “next year is very important for my family.” He said he has several commitments “which I simply cannot risk missing.” A Boeing spokeswoman confirmed one is his daughter’s wedding. “I’m not going anywhere. I’m just not going into space next year,” Ferguson said. He stressed that he remains committed to the Starliner program and will continue to work for Boeing.

This is the second crew change for this mission. Earlier NASA astronaut Eric Boe had had to back out due to medical reasons.

Assuming the second unmanned Starliner demo mission scheduled for the December-January timeframe succeeds, the first manned mission will happen in June ’21, and last anywhere from two weeks to six months.

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Military considering using Starship for point-to-point transportaion

9:13 am

Capitalism in space: The U.S. military has begun a study in partnership with SpaceX on whether it will be possible to use Starship as a cargo ship for moving large shipments from point-to-point on the Earth.

Army Gen. Stephen Lyons, commander of U.S. Transportation Command, announced the agreement Oct. 7 at a National Defense Transportation Association virtual conference. “Think about moving the equivalent of a C-17 payload anywhere on the globe in less than an hour,” Lyons said. The C-17 is a very large military cargo plane capable of transporting a 70-ton main battle tank.

Makes sense. This decision also suggests the military is impressed with SpaceX’s progress on Starship, and has also largely abandoned its earlier skepticism of the company.

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A typical mid-latitude Martian crater with glacial features

2:22 pm

Typical mid-latitude Martian crater with glacial fill
Click for full image.

Cool image time! The crater on the right, the image cropped and reduced to post here, is a great example of many craters scientists have found in the mid-latitudes on Mars containing a variety of features that suggest buried glaciers. In this case we are looking at what they have dubbed a concentric crater fill, material that resembles glacial material that fills the crater’s interior and floor, and appears often to erode in a series of rings. You can see another example here.

The photo was taken on June 29, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). The crater itself is located in a region of chaos terrain dubbed Nilosyrtis Mensae, located in the transition zone between the cratered southern highlands and the lowland northern plains.

Nilosyrtis Mensae is part of a region of Mars I call glacier country. When you include the mensae regions Protonilus and Deuteronilus to the west, this transition zone of random mesas, knobs, and criss-crossing canyons stretches about 2,000 miles. The context map below focuses in on Nilosyrtis Mensae, where this crater is located.
» Read more

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Government takes down pro-Trump sign on private property, without permission

10:46 am

They’re coming for you next: California state officials quickly moved to take down a pro-Trump billboard, even though it was on private property and they apparently did not have permission to do so.

This LA Times report on the massive Trump sign on a hill near the 405 says that state authorities went on private property to take it down because they claimed the political speech was a “visual distraction” to drivers.

So, in California your first, fourth, fifth, and sixth amendment rights are now null and void. If government officials don’t approve of your political signage, they now claim the right to enter your property, without permission and without a search warrant, and take down your signage.

The article at the first link notes that for some reason, these same California authorities did not consider it a “visual distraction” for Antifa and Black Lives Matter protests to stand on these same highways and block traffic.

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Radio astronomers claim negative impact from satellite constellations

10:35 am

Put them on the Moon! Radio astronomers have released a paper claiming that the coming large communication satellite constellations, such as Starlink and OneWeb, will seriously impact observations with the Square Kilometer Array (SKA) of radio telescopes being built in the remote western outback of Australia.

Saturation of the instruments: very strong interfering signals can saturate the receiver systems and thereby drown out all other signals seen by the Band 5b receivers. As a consequence, all data in that frequency band would be lost, rendering these receivers useless for a portion of the time. For the first phase of the constellation deployments (about 6,400 satellites in total), saturation is predicted to occur for a few percent of the time assuming there is no direct illumination of the dishes by the satellites. For significantly larger constellation sizes (up to more than 100,000 satellites), saturation would be essentially continuous without significant mitigation measures implemented by the satellite operators.

Based on this conclusion, the astronomers estimate that for observations in this particular band they will need to look about 70% longer to get the same data, thereby cutting the number of observations by about half.

The astronomers propose this solution:

One of these mitigation techniques is for the satellite transmitters not to point their beams near the SKAO dishes. SKAO would require operators to steer their satellites’ beams away from the telescope site, a measure which would require a simple software modification with no repercussion on the constellation’s deployment, positioning or hardware. While a cost-effective implementation of this solution does depend on the hardware and software deployed on the satellites, operators already use this technique to comply with international regulations when their satellites cross the path between geostationary satellites in higher orbit and their receiving ground stations, for example to avoid affecting telecommunications and TV transmissions.

This mitigation could reduce the impact on the SKA by a factor of 10 over that noted previously and result in a 7% increase of integration time for SKA observations within the satellite transmission range 4. While any loss of sensitivity is regrettable, SKAO recognises the need for compromise between the competing scientific and commercial drivers.

The solution seems reasonable, but in truth it is only a temporary one. The permanent and smart solution for the astronomical community is to move their telescopes, in all wavelengths, off the Earth. For radio astronomy the far side of the Moon would be ideal.

And with SpaceX now developing a reusable big rocket, Starship, to put such payloads in orbit at low cost, the astronomers need to start thinking about taking advantage of this engineering. The situation for ground-based astronomer will only get worse.

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