Category: Behind The Black

Cloud stream on Jupiter

9:21 am

Cloud stream on Jupiter
Click for full image.

Cool image time! The photo to the right, taken by Juno on November 3, was enhanced by citizen scientist Björn Jónsson to bring out the colors. It shows a band of repeating large storms, with tiny white thunderheads popping up within them.

The dark areas at the edges of the swirls are likely not an aspect of the clouds but shadows created because the white swirls sit higher than the surrounding gases.

Sadly the press release does not give us a scale. The image was taken from a distance of 3,200 miles. I suspect each cloud swirl would likely cover much of the Earth.

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Inmarsat bought out and delisted from stock exchange

9:07 am

Capitalism in space: The long established communications satellite company Inmarsat has been bought out by a consortium called Connect Bidco and delisted from stock exchange.

Nor is Inmarsat alone:

Inmarsat is the third satellite operator to delist from public markets this year, following Hong Kong-based AsiaSat and London-based Avanti in September.

Inmarsat reported a loss of $89.1 million on $1.06 billion in revenue for the first nine months of the year. The company claimed $36.1 million in profits on $327.3 million in revenue for the months of July, August and September — it’s last public quarter before the buyout.

This story and the quote above explain what is happening. Established satellite companies, that traditionally have built big geosynchronous satellites, are having increased trouble making money as the industry shifts to smaller satellite and constellations in low Earth orbit.

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Successful Russia and Rocket Lab launches

8:52 am

Two launches successfully took place in the early morning hours today. First Rocket Lab launched seven small satellites into orbit, including one that will release an artificial meteor shower. During that launch they also obtained telemetry of their first stage as it fell to Earth.

Rocket Lab CEO Peter Beck just tweeted that the Electron’s first stage performed well during today’s re-entry experiment. “Electron made it through wall! Solid telemetry all the way to sea level with a healthy stage. A massive step for recovery!!” Beck tweeted.

Russia in turn launched a Progress cargo capsule to ISS.

The leaders in the 2019 launch race:

27 China
19 Russia
12 SpaceX
7 Europe (Arianespace)
6 Rocket Lab

China now leads the U.S. 27 to 25 in the national rankings.

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Lloyd’s introduces new insurance policy for smallsats

10:57 am

Capitalism in space: The insurance company Lloyd’s today introduced a new insurance policy expressly designed for the emerging smallsat launch industry.

The solution – called “Llift Space” – is only available in the Lloyd’s market and allows customers to cover their assets from the pre-launch phase, including transit and placement on the launch vehicle, through to the launch phase and in-orbit operation. It is designed for satellites that weigh less than 300 kilograms (661.4 pounds).

The policy is modular so customers can choose the elements within each phase that are most relevant to their coverage needs.

The product is backed by a consortium of 18 syndicates, led by Brit and Hiscox MGA, with $25 million capacity per risk, and is targeted at the NewSpace sector.

NewSpace is characterized by lower cost, easier routes to space, opening up the sector to private enterprise, wealthy entrepreneurs and innovative start-ups. This is increasing the need for space insurance.

This action is a strong endorsement by the investment business in the future of the new smallsat launch industry.

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SpaceX targets December for launch abort test, early 2020 for 1st manned Dragon mission

10:22 am

According to SpaceX officials, the company is aiming to perform its Dragon launch abort test before the end of this month, and then follow-up with the first manned Dragon mission to ISS in early 2020.

“We’re targeting December,” said [Jessica Jensen, director of Dragon Mission Management at SpaceX] today (Dec. 3) during a news conference discussing tomorrow’s (Dec. 4) planned launch of a robotic Dragon cargo mission to the International Space Station (ISS). “We’ll see if we can get there.”

SpaceX holds a multibillion-dollar NASA contract to ferry astronauts to and from the ISS using Crew Dragon and the Falcon 9. The capsule has already visited the orbiting lab once, on the landmark uncrewed Demo-1 mission this past March. If everything goes well with the [launch abort test], the company will be cleared for the first crewed mission — a test flight known as Demo-2 that will carry NASA astronauts Doug Hurley and Bob Behnken.

Demo-2 is targeted for early 2020, SpaceX founder and CEO Elon Musk has said. Contracted, operational ISS flights would follow shortly thereafter.

NASA officials have repeatedly said that early 2020 is too soon because of the paperwork that SpaceX has to complete prior to launch. It could be that Musk is gently applying pressure on them here to speed up this make-work so that the real business of spaceflight can proceed.

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OSIRIS-REx completes reconnaissance of four candidate sample sites

10:04 am

Four candidate landing sites
Click for full image.

OSIRIS-REx has completed its high resolution reconnaissance of the four candidate sites on the asteroid Bennu, chosen for possible sample capture during touch-and-go operations planned for the summer of 2020.

In the next few days the science team will decide which of these four sites, shown above, will be the primary and back-up landing locations. The decision however appears challenging, based on the information gathered.

Bennu has also made it a challenge for the mission to identify a site that won’t trigger the spacecraft’s safety mechanisms. During Recon A, the team began cataloguing Bennu’s surface features to create maps for the Natural Feature Tracking (NFT) autonomous navigation system. During the sample collection event, the spacecraft will use NFT to navigate to the asteroid’s surface by comparing the onboard image catalog to the navigation images it will take during descent. In response to Bennu’s extremely rocky surface, the NFT system has been augmented with a new safety feature, which instructs it to wave-off the sampling attempt and back away if it determines the point of contact is near a potentially hazardous surface feature. With Bennu’s building-sized boulders and small target sites, the team realizes that there is a possibility that the spacecraft will wave-off the first time it descends to collect a sample.

Based on the information at the link, plus the presentation by Dante Lauretta, OSIRIS-REx’s principal investigator, given at the asteroid conference I attended in November, I suspect that Nightingale will be primary landing site.

Regardless, it appears the science team has recognized that the landing will difficult, and will likely require multiple attempts before the spacecraft’s navigation system lets it happen.

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First results from Parker released

1:11 pm

Scientists today published four papers outlining the first scientific results obtained during the first two close fly-bys of the Sun by the Parker Solar Probe.

The four papers, now available online from the journal Nature, describe Parker’s unprecedented near-Sun observations through two record-breaking close flybys. They reveal new insights into the processes that drive the solar wind – the constant outflow of hot, ionized gas that streams outward from the Sun and fills up the solar system – and how the solar wind couples with solar rotation. Through these flybys, the mission also has examined the dust of the coronal environment, and spotted particle acceleration events so small that they are undetectable from Earth, which is nearly 93 million miles from the Sun.

During its initial flybys, Parker studied the Sun from a distance of about 15 million miles. That is already closer to the Sun than Mercury, but the spacecraft will get even closer in the future, as it travels at more than 213,000 mph, faster than any previous spacecraft.

Details about the four main takeaways are described at the link. None of the discoveries is earth-shaking but all help scientists better understand the Sun’s inner atmosphere.

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SpaceX to test upper stage endurance as part of Dragon launch

12:52 pm

Capitalism in space: SpaceX plans to perform a six hour orbital coast test of its Falcon 9 upper stage following the release of the Dragon cargo capsule tomorrow (scrubbed today due to high winds).

This is why the first stage will land on a drone ship rather than at Kennedy.

According to SpaceX the test is at the request of “other customers”, unnamed. The article adds this speculation:

Jensen says that the coast test will be performed for unspecified “other” customers, presumably referring to the US Air Force (USAF) and other commercial customers interested in direct-to-geostationary (GEO) launch services. Direct GEO launches require rocket upper stages to perform extremely long coasts in orbit, all while fighting the hostile vacuum environment’s temperature swings and radiation belts and attempting to prevent cryogenic propellant from boiling off or freezing solid. In simple terms, it’s incredibly difficult to build a reliable, high-performance upper stage capable of remaining fully functional after 6-12+ hours in orbit.

Although SpaceX said that the test was for “other” customers, that may well have been a cryptic way to avoid indicating that one such customer might be NASA itself. NASA is in the midst of a political battle for the Europa Clipper spacecraft’s launch contract, which is currently legally obligated to launch on NASA’s SLS rocket. Said rocket will likely cost on the order of >$2 billion per launch, meaning that simply using Falcon Heavy or Delta IV Heavy could save no less than ~$1.5 billion. Incredibly, that means that simply using a commercial launch vehicle could save NASA enough money to fund an entire Curiosity-sized Mars rover or even a majority of the cost of building a dedicated Europa lander. Such a launch would demand every ounce of Falcon Heavy’s performance, including a very long orbital coast.

These speculations could all be true. SpaceX might merely be doing what it always does, testing new engineering upgrades during operational missions. It will then be able to sell its rocket’s enhanced capability to all these customers.

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China to launch 30 times in 2020

12:35 pm

The new colonial movement: According to Chinese officials, China plans to launch 30 times in 2020, maintaining the same pace that they met in 2019.

Zhuang Jingguo, chief engineer of the China Aerospace Science and Technology Corporation (CASC), the country’s man space contractor, told media at the Fifth China International Commercial Aerospace Forum late last month that the state-owned enterprise will launch around 30 rockets next year.

This number is expected to include missions to Mars, the moon, test flights of new launch vehicles, and the completion of the Beidou navigation system. Commercial launch companies will further add to Chinese launch activities.

The article also provides a good overall summary of China’s present space effort, which is extensive and growing.

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Bridenstine: SLS costs less than $2 billion per launch

12:30 pm

During an agency meeting where the new manager of NASA’s manned program officially took charge, administrator Jim Bridenstine expressed disagreement with a Trump administration estimate of $2 billion for each SLS launch.

The OMB letter used “over $2 billion” as the estimated cost of an SLS launch, arguing that is $1.5 billion more than a commercial launch. The $2 billion figure has been widely cited since then as an official cost estimate.

Bridenstine was asked about it today, and disagreed. “I do not agree with the $2 billion number. It is far less than that. I would also say the number comes way down when you buy more than one or two. I think in the end we’re going to be in the $800-900 million range.” NASA has bought only two SLS launches so far and negotiations are just starting on the third and fourth, he added. [emphasis mine]

Well that solves everything! SLS will only cost a little less than a billion per launch, not two billion. Any fool can see this is clearly competitive with the $100 million that SpaceX charges for each Falcon Heavy launch. And you’d have to do two Falcon Heavy launches to match what SLS can do in one launch. Obviously we want to buy SLS! It’s what any Washington lawmaker or bureaucrat would clearly conclude.

The article notes that NASA has only “bought two SLS launches” but fails to explain why. This is all that Congress has appropriated. NASA is negotiating with Boeing to build as many as ten more, but as far as I know, the authorization from lawmakers has not yet been given to do so.

But then, why not? We are no longer ruled by our elected officials, but by the unelected bureaucrats who live high on the hog in their plush Washington digs.

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Chang’e-4 and Yutu-2 complete 12th lunar day

12:17 pm

Chinese engineers have put both Chang’e-4 and Yutu-2 into dormant mode after completed their twelve lunar day on the far side of the Moon.

The article from the Chinese state-run press provides very little information, other than telling us that Yutu-2 traveled 345 meters, written in a way to imply that was the distance the rover traveled in this last lunar day. I think that is wrong, however. Based on the distances traversed during previous lunar days, and that the rover had traveled a total of 290 meters at the end of its tenth lunar day, I think this new number is the total distance traveled.

The article also does not say what the consequences will be for these two spacecraft now that the priority of their communications relay has shifted from communications to being a radio telescope.

It could be that the consequences will be minor, considering that both spacecraft are in sleep mode during the lunar nights and for high noon of the lunar day. During those periods the relay satellite could be devoted full time to radio astronomy and have no impact on the lander and rover.

Unfortunately China has not said.

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A home-made plane

6:04 pm

An evening pause: Another example of someone who decides he wants to do something, and then goes out and does it. This STOL (short take-off and landing) home-built plane, dubbed Draco, was apparently a big hit in the small plane community. Sadly, in September the plane was totaled (no injuries) during a take-off with strong cross winds (video here).

Hat tip Cotour.

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TESS captures outburst from comet

5:42 pm

Wirtanen outburst

The space telescope TESS, designed to look for exoplanets by imaging one hemisphere of the sky repeatedly over a full year, also successfully captured in those images the full outburst from the comet 46P/Wirtanen that occurred on September 26, 2018.

The animation created from those images is to the right.

According to Farnham, the TESS observations of comet Wirtanen were the first to capture all phases of a natural comet outburst, from beginning to end. He noted that three other previous observations came close to recording the beginning of an outburst event. Observations of a 2007 outburst from comet 17P/Holmes began late, missing several hours of the initial brightening phase of the event. In 2017, observations of an outburst from comet 29P/Schwassmann-Wachmann 1 (SW1) concluded early, due to limitations on pre-scheduled observation time. And, while observations from the UMD-led Deep Impact mission captured an outburst from comet Tempel 1 in unprecedented detail in 2005, the outburst was not natural—created instead by the mission’s impactor module. However, the current observations are the first to capture the dissipation phase in its entirety, Farnham said.

Although Wirtanen came closest to Earth on December 16, 2018, the outburst occurred earlier in its approach, beginning on September 26, 2018. The initial brightening of the outburst occurred in two distinct phases, with an hour-long flash followed by a more gradual second stage that continued to grow brighter for another 8 hours. This second stage was likely caused by the gradual spreading of comet dust from the outburst, which causes the dust cloud to reflect more sunlight overall. After reaching peak brightness, the comet faded gradually over a period of more than two weeks. Because TESS takes detailed, composite images every 30 minutes, the team was able to view each phase in exquisite detail.

The data from TESS is likely going to overwhelm the astronomy community for years.

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New analysis suggests dark energy might not be necessary

5:29 pm

The uncertainty of science: A new peer-reviewed paper in a major astronomy science journal suggests that dark energy might not actually exist, and that the evidence for it might simply be because the original data was biased by the Milky Way’s own movement.

What [the scientists in this new paper] found is that the best fit to the data is that the redshift of supernovae is not the same in all directions, but that it depends on the direction. This direction is aligned with the direction in which we move through the cosmic microwave background. And – most importantly – you do not need further redshift to explain the observations.

If what they say is correct, then it is unnecessary to postulate dark energy which means that the expansion of the universe might not speed up after all.

Why didn’t Perlmutter and Riess [the discoverers of dark energy] come to this conclusion? They could not, because the supernovae that they looked were skewed in direction. The ones with low redshift were in the direction of the CMB dipole; and high redshift ones away from it. With a skewed sample like this, you can’t tell if the effect you see is the same in all directions.

The link is to a blog post by a physicist in the field, commenting on the new paper. Below the fold I have embedded a video from that same physicist that does a nice job of illustrating what she wrote.

This paper does not disprove dark energy. It instead illustrates the large uncertainties involved, as well as show solid evidence that the present consensus favoring the existence of dark energy should be questioned.

But then, that’s how real science works. When the data is sketchy or thin, with many assumptions, it is essential that everyone, especially the scientists in the field, question the results. We shall see now if the physics community will do this.

Hat tip to reader Mike Nelson.

» Read more

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A crack in the Martian crust

3:39 pm

Crack in the Martian crust
Click for full image.

Cerberus Fossae

The photograph to the right, reduced and cropped to post here, was imaged on October 20, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a spectacular thousand-foot-deep canyon in the region of Cerberus Fossae, an area of Mars crossed by numerous deep east-west fissures and depressions.

Hidden in the small white box on the eastern end of that canyon are Martian geological features, small and at first glance not that interesting, that are of great significance and the focus of intense research.

The map to the right shows an overview of the region. The yellow cross shows the location of this particular crack.

In my previous post about Cerberus Fossae, I had incorrectly assumed that these cracks and similar lines of pits or depressions were caused by the sinking of surface material into underground lava tubes. While this is possible in some cases, it is not the main cause of these cracks. Instead, they were formed due to the pressure from below caused by the rise of the surrounding giant volcanoes, Elysium Mons to the north and Olympus Mons to the east. That pressure stretched the crust until it cracked in numerous places. In Cerberus Fossae this produced a series of parallel east-west fissures, some more than seven hundred miles long.

The young age of Cerberus Fossae is dramatically illustrated by the wider mosaic below, showing the entire crack.
» Read more

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Harris’s exit from presidential race highlights again the bigotry of the Democratic Party

3:10 pm

Today Kamala Harris announced she is dropping out of the race to be the Democratic Party’s presidential candidate.

Not surprisingly, activists in the Democratic Party immediately blamed racism for her failure. From the leftist New York Times:

Still, Ms. Harris had already qualified for the next presidential debate, scheduled for Dec. 19, the only non-white candidate to do so thus far. Without her, Democrats may have an all-white debate stage after beginning the primaries with the most racially diverse field in history, though candidates like Representative Tulsi Gabbard of Hawaii and businessman Andrew Yang may still qualify in the coming days.

“No matter your candidate, you have to recognize that going from the most diverse field ever in January to a potentially all-white debate stage in December is catastrophic,” wrote Leah Greenberg, a co-executive director of Indivisible, a national progressive group, on Twitter.

…“She really showed the importance of having different perspectives on the debate stage,” said Amanda Hunter, research and communications director at the Barbara Lee Family Foundation, which supports women in politics and studies double standards. “Her personal story about being bused to school was something that a historically typical older white man would not bring to the conversation.”

But “there is still a very entrenched stereotype of what a presidential candidate looks like in this country,” Ms. Hunter said. “Simply by running, Senator Harris challenged that and broke down stereotypes. But a lot of the questions around electability and the challenges she faced were probably motivated by that entrenched stereotype that so many people held.” [emphasis mine]

Note how everything to these Democrat officials is based on race. Everything. To them, Harris lost because she wasn’t white, and because Americans can only conceive a white man as president.

Of course, this thinking is quite idiotic, considering that these same Americans voted twice for a black president, in 2008 and 2012. That’s hardly ancient history.

The only diversity that should matter is diversity of thought, of ideas, of policy suggestions. Among Democrats that’s the last thing we’ve seen in the past three years. All they have shown us is hate and opposition to all things Trump, followed by a desire to destroy the free capitalist United States and replace it with their warped view of the Soviet Union.

If you are normal decent person who happens to belong to the Democratic Party and routinely vote for them, be aware that this party is not the party you think it is. These comments above illustrate again the corrupt, racist, and bigoted make-up of the party’s power structure. They hate Trump, they hate ordinary whites, they hate freedom, and they hate you, if you oppose them in any way at all, even if you have been a loyal Democrat for decades.

For my part Harris’s exit is a great relief. She has repeatedly demonstrated her fascist tendencies in recent years.

I suspect this history had a lot more to do with her failure than her skin color.

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Ukraine’s president reiterates: No quid pro quo from Trump

8:46 am

Democratic Party coup update: The president of the Ukraine yesterday once again stated that President Trump applied no pressure on him to begin an investigation into Joe Biden.

Once again, Ukrainian President Volodymyr Zelensky has denied again that President Trump withheld military aid in order to pressure him to investigate the Bidens or Ukrainian election interference. In an interview with TIME magazine, Zelensky made this absolutely clear. “Look, I never talked to the President from the position of a quid pro quo. That’s not my thing,” he said. “I don’t want us to look like beggars. But you have to understand. We’re at war. If you’re our strategic partner, then you can’t go blocking anything for us. I think that’s just about fairness. It’s not about a quid pro quo. It just goes without saying.”

This is not the first time he has stated this publicly. Furthermore, his foreign minister has said the same thing, as has the U.S. ambassador during testimony to Congress.

On the other side, the accusations of misbehavior from Democratic Party witnesses have either been hearsay from people not even present during Trump’s phonecalls with Zelinsky, or from low-level bureaucrats who merely have a difference of opinion with Trump about U.S. foreign policy. I don’t remember however ever voting for them for President. Do you?

This ridiculous effort by the Democrats to overturn a legal election would be hilarious if it wasn’t so offensive. However, increasingly it appears it is serving a good end, as it is revealing their power-hungry, totalitarian, and anti-democratic culture to the entire country. They don’t support democracy and elections, only their guaranteed unopposed right to rule. Such people should never be given positions of power, and if they manage to do so, they should be removed by the voters as soon as possible.

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Long March-8 2nd stage engine passes engine test

8:31 am

The new colonial movement: The second stage engine for China’s new Long March-8 rocket has successfully passed its engine tests.

Developed by the CASC [China Aerospace Science and Technology Corporation, China’s equivalent to NASA], the Long March-8 rocket is a new type of rocket that uses module design and can be prepared in a short time, making it competitive for commercial launch.

The first stage of the Long March-8 rocket is similar to that of the Long March-7 rocket and the second stage rocket is similar to the third stage of the Long March-3A rocket. It has a payload capacity of 5 tonnes to sun-synchronous orbit and 2.8 tonnes to geostationary transfer orbit.

This payload capacity is about a fourth that of the Falcon 9, but because the weight and size of satellites is shrinking, that smaller capacity might actually be an advantage. There is less need for the larger rockets in the commercial unmanned satellite industry, so for China to build a new smaller rocket that can be launched for less, even though it is not reusable, gives them a route for competing with SpaceX’s reuseability.

They hope to launch 10 to 20 times per year, beginning next year.

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Hayabusa-2 fires main ion engines for return to Earth

8:20 am

After spending two weeks testing its main ion engines just beyond the gravitational sphere of influence of the asteroid Ryugu, Japanese engineers today initiated full engine operation, beginning the spacecraft’s journey back to Earth.

Hayabusa-2 is expected to return to Earth space in December 2020, where it will release a small capsule containing the two samples it obtained of Ryugu will be released to land on Earth and be recovered. At that point, if Hayabusa-2 is still in good condition it will be available to send to other locations in the solar system.

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Astronomers find record-setting heaviest supermassive black hole

8:05 am

Astronomers have discovered the most massive black hole yet discovered, having a mass 40 billion times the mass of our Sun.

The new data obtained at the USM Wendelstein observatory of the Ludwig-Maximilians-University and with the MUSE instrument at the VLT [Very Large Telescope in Chile] allowed the team to perform a mass estimate based directly on the stellar motions around the core of the galaxy. With a mass of 40 billion solar masses, this is the most massive black hole known today in the local universe. “This is several times larger than expected from indirect measurements, such as the stellar mass or the velocity dispersion of the galaxy,” remarks Roberto Saglia, senior scientist MPE and lecturer at the LMU.

The light profile of the galaxy shows a centre with an extremely low and very diffuse surface brightness, much fainter than in other elliptical galaxies. “The light profile in the inner core is also very flat,” explains USM doctoral student Kianusch Mehrgan, who performed the data analysis. “This means that most of the stars in the centre must have been expelled due to interactions in previous mergers.”

To give some perspective, the mass of the supermassive black hole in the center of the Milky Way, Sagittarius A* (pronounced A-Star), is thought to be about 4.6 million solar masses. This newly discovered supermassive black hole is almost nine thousand times heavier.

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Crash site of Vikram found

4:09 pm

Vikram impact point
Click for full image.

Using a mosaic of Lunar Reconnaissance Orbiter (LRO) images, citizen scientist Shanmuga Subramanian located on the Moon the debris and impact point for India’s Vikram lander that crashed there in September, an identification that has since been confirmed by LRO scientists.

The image on the right, reduced to post here, has been modified by the scientists to bring out the features that changed before and after the impact.

After receiving this tip the LROC team confirmed the identification by comparing before and after images. When the images for the first mosaic were acquired the impact point was poorly illuminated and thus not easily identifiable. Two subsequent image sequences were acquired on 14, 15 October and 11 November. The LROC team scoured the surrounding area in these new mosaics and found the impact site (70.8810°S, 22.7840°E, 834 m elevation) and associated debris field. The November mosaic had the best pixel scale (0.7 meter) and lighting conditions (72° incidence angle).

The debris first located by Shanmuga is about 750 meters northwest of the main crash site and was a single bright pixel identification in that first mosaic (1.3 meter pixels, 84° incidence angle). The November mosaic shows best the impact crater, ray and extensive debris field. The three largest pieces of debris are each about 2×2 pixels and cast a one pixel shadow.

No word yet on what this new information reveals about Vikram’s failure.

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Martian “What the heck?” formations

2:41 pm

What the heck caused these?
Click for full image.

Cool image time! In digging through the new images that come down from the high resolution camera on Mars Reconnaissance Orbiter (MRO), my reaction sometimes is “What the heck caused that?”

That was my reaction when I looked at the image to the right, cropped to post here.

The full image, taken on October 6, 2019, shows the floor of one of the many north-south fissures found in the volcanic Tharsis Bulge west of Valles Marineris and east of Olympus Mons. The fissures are caused when the crust is pushed upward by volcanic pressure, causing the surface to crack.

In this case the mystery is that patch of east-west ridges at the bottom of this somewhat wide fissure. While they might be dunes, they do not resemble dunes, as they have a rigid and somewhat sharp appearance. More puzzling is their somewhat abrupt appearance and disappearance. Except for its northern end, the edges of the patch are so sharply defined. If these were dunes you’d think they’d fade away more gradually.

Could the ridges be a more resistant subsurface feature slowly being revealed as surface material erodes away? Sure, but their orientation is completely opposite to the north-south fissures that dominate this region. One would expect deeper features to reflect that same general orientation. These ridges do not.

This image was dubbed a “Terrain Sample,” which means it was taken not because of any specific research goal, but because the scientists who run MRO’s high resolution camera had a gap in their schedule and needed to take a picture to maintain the camera’s proper temperature. In such cases they often take somewhat random images, not knowing what they will find. In this case they struck geological gold, a mystery that some postdoc student could spend a lot of time analyzing.

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New Horizons confirms solar wind slows at greater solar distances

9:57 am

The New Horizons science team today released data that confirms that, as theorized, the speed of the solar wind decreases as it travels farther from the Sun.

As the solar wind moves farther from the Sun, it encounters an increasing amount of material from interstellar space. When interstellar material is ionized, the solar wind picks up the material and, researchers theorized, slows and heats in response. SWAP [an instrument on New Horizons] has now detected and confirmed this predicted effect.

The SWAP team compared the New Horizons solar wind speed measurements from 21 to 42 astronomical units to the speeds at 1 AU from both the Advanced Composition Explorer (ACE) and Solar TErrestrial RElations Observatory (STEREO) spacecraft. (One AU is equal to the distance between the Sun and Earth.) By 21 AU, it appeared that SWAP could be detecting the slowing of the solar wind in response to picking up interstellar material. However, when New Horizons traveled beyond Pluto, between 33 and 42 AU, the solar wind measured 6-7% slower than at the 1 AU distance, confirming the effect.

The data also suggests that New Horizons could exit the heliosphere and enter interstellar space as early as sometime in the 2020s.

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