Year: 2019

Watching the yearly vanishing of Mars’ north pole dry icecap

12:45 pm

Buzzell dunes, March 19, 2019
Click for full image.

Buzzel dunes, April 4, 2019
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Buzzell dunes, June 4, 2019
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For the northern hemisphere of Mars it is presently spring. The season began sometime in April 2019 and will last until about October, twice as long as on Earth because of the Martian year is twice as long.

During the fall and winter the permanent water-icecap, which forms the bulk of the Martian icecap, gets covered by a mantle of dry ice, settling there as a layer of carbon dioxide snow about six feet thick. With the arrival of spring that dry icecap slowly begins sublimate away entirely.

Using the high resolution camera on Mars Reconnaissance Orbiter (MRO) planetary scientists are monitoring this process, taking pictures periodically.

On June 6, 2019 I had written a detailed story describing the Martian North Pole and outlining the process by which this sublimation of the dry icecap mantle takes place.

When winter ends and the sun reappears at this Arctic location, a small percentage of that sunlight, about 10%, goes through the dry ice and warms the sand that the dry ice mantles. This in turn warms the bottom of the dry ice layer, causing this to sublimate into a gas that is now trapped.

When the pressure builds sufficiently, that gas breaks free at the weakest spots in the dry ice layer, which are either at the dune crest or at its base, or sometimes on its face where cracks form. When it does so the CO2 gas carries with it material from below, which appears dark relative to the bright dry ice on the surface. As the summer season progresses and more dry ice sublimates away, the dark smudges disappear as they slowly blend in with the now-exposed original sand surface.

The first two pictures to the right were posted in that June 6, 2019 story, showing the initial evidence of sublimation on a set of dunes that the scientists have dubbed Buzzell. Below these, I have now added the newest image of the Buzzell dunes, taken on June 4, 2019 and just released in the August MRO image dump.

When this third image was taken, spring was only about two months old. Yet, this sublimation process is clearly accelerating. You can see many more dark patches at the crests and bases of many dunes, especially in the upper left of the image. According to Dr. Candice Hansen of the Planetary Science Institute in Tucson, Arizona, who is requesting these monitoring images, by sometime in October “you’ll see how the entire spring progresses from dunes completely covered with dry ice to the summer when they are just bare sand. Then you could comment on the whole spring series.”

I fully intend to do this. No harm however in providing an interim report or two. Stay tuned to Behind the Black for future on-going and up-to-date reports on the shrinking north pole dry icecap of Mars!

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IAU approves 2nd set of Pluto names chosen by New Horizons team

8:47 am

My heart be still! The International Astronomical Union (IAU) has now officially given its glorious stamp of approval to a second set of fourteen names given by the New Horizons’ team to features on Pluto.

Several people and missions who paved the way for the historic exploration of Pluto and the Kuiper Belt – the farthest worlds ever explored – are honored in the second set of official Pluto feature names approved by the International Astronomical Union (IAU), the international authority for naming celestial bodies and their surface features.

The new names were proposed by NASA’s New Horizons team, which carried out the first reconnaissance of Pluto and its moons with the New Horizons spacecraft in 2015. Along with a short list of official names the IAU had already approved, the mission science team had been using these and other place names informally to describe the many regions, mountain ranges, plains, valleys and craters discovered during the first close-up look at Pluto’s surface. [emphasis mine]

In case you don’t get it, I am being very sarcastic above. I consider the IAU to be incredibly arrogant in its claim that it, and it alone, can approve the names given to surface features on other worlds. Initially the IAU was given the task by the astronomical community of organizing the naming of celestial bodies seen in telescopes, to reduce confusion. Somehow the IAU has expanded that responsibility to include the naming of every rock and pebble on every world in the universe.

To this I say bunk. I also know that future spacefarers in space will say the same thing, and tell the IAU to go jump in a lake. In a sense, the New Horizons team did exactly that when they made their name choices very public from the beginning, essentially telling the IAU that the New Horizons’ team is picking the names, not the IAU.

In related news, the IAU has now approved the naming convention the OSIRIS-REx team intends to use to name features on Bennu. However, in this case the IAU is doing its real job, helping to organize the naming conventions to reduce confusion.

The named features on Bennu will include several terrain classification types that the IAU also approved for asteroid (162173) Ryugu’s surface features (currently being explored by the Japanese Space Agency’s Hayabusa2 spacecraft). These include craters, dorsa (peaks or ridges), fossae (grooves or trenches) and saxa (rocks and boulders). The last of these types – saxum – is a new feature classification that the IAU introduced earlier this year for small, rocky asteroids like Ryugu and Bennu. These surface features on Bennu will be named after mythological birds and bird-like creatures, complementing the mission’s existing naming theme, which is rooted in Egyptian mythology.

The actual names the OSIRIS-REx team will chose for each unique feature will however be their choice, not the IAU’s. Though the IAU will eventually announce it has “approved” those choices, it will never really have the right to have a say in those decisions.

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OneWeb: LauncherOne too expensive

8:30 am

In asking that Virgin Orbit’s lawsuit against internet satellite manufacturer OneWeb be dismissed, OneWeb has claimed that their contract allowed for the cancellation of launches without cause, and that they have a cause anyway, which is that LauncherOne is too pricey.

In its court filing, OneWeb said the $6 million price tag for a LauncherOne mission is two to three times current market prices.

…The original contract, OneWeb claims, allowed for termination without cause, and for prior payments to apply to the termination fee. Those contract termination rules, and the fact that Virgin Orbit has yet to conduct any LauncherOne missions, invalidate Virgin Orbit’s revenue expectations, according to OneWeb. [emphasis mine]

Based on my estimate of the launch market, LauncherOne’s price is higher than others, but not by very much. I think the highlighted text is more significant. LauncherOne had announced plans to fly its first mission last summer. More than a year later that inaugural flight has still not taken place.

In the meantime, this decision by OneWeb is a boon to Russia’s space industry, especially its Soyuz rocket, as it will now get the contracts for launching the majority of OneWeb’s 648-satellite constellation.

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New Hubble image of Jupiter

5:39 pm

Jupiter as seen by Hubble in 2019
Click for full image.

The Hubble science team today released a new global image the telescope took of Jupiter on June 27, 2019. The photograph on the right is that image, reduced and cropped to post here. As noted by the press release about the Great Red Spot,

The Great Red Spot is a towering structure shaped like a wedding cake, whose upper haze layer extends more than 3 miles (5 kilometers) higher than clouds in other areas. The gigantic structure, with a diameter slightly larger than Earth’s, is a high-pressure wind system called an anticyclone that has been slowly downsizing since the 1800s. The reason for this change in size is still unknown.

A worm-shaped feature located below the Great Red Spot is a cyclone, a vortex around a low-pressure area with winds spinning in the opposite direction from the Red Spot. Researchers have observed cyclones with a wide variety of different appearances across the planet. The two white oval-shaped features are anticyclones, like small versions of the Great Red Spot.

Another interesting detail is the color of the wide band at the equator. The bright orange color may be a sign that deeper clouds are starting to clear out, emphasizing red particles in the overlying haze.

In many ways Hubble’s images of Jupiter are comparable to those taken by Juno, except that Hubble can’t zoom in as close.

2 comments

Are you a decent human being?

2:46 pm

In recent weeks I have grown so horrified by the blatant hate being screamed by Democrats and leftists in the mainstream press against Republicans, conservatives, and Trump supporters that I have found myself unable to write about this stuff.

It is just too disgusting. Here are just a few examples that barely represent the full gamut of anger and hate being expressed by Democrats and their willing accomplices in the press:

All of the accusations against Trump and Republicans in these stories are outright lies, worthy of Joseph Goebbels. And the actions of Democratic politicians like Biden and Castro to attack and smear Trump and his supporters is equally vile, and worthy of the worst form of scapegoating done by anti-Semites. Worse, these people are using terrible mass murders, committed by clearly unstable and sick individuals, to score political points. Such behavior is beyond the pale.

One might, if one was willing to stretch the truth beyond the breaking point, to find some justification in the criticisms of Trump. However, though Trump’s twitter comments are often ugly and crude and insulting, the one thing a careful reading of all those statements reveals is that he has always tried to state the truth, honestly and bluntly. Moreover, there is no evidence of racism in any of his comments. He has merely been attacking those who deserve attacking.

The Democratic attacks, however, on the decency of the American population, especially its non-minority population, are especially vile and dishonest. Remember, this is the same population that only a few years ago twice voted for a black president. For Democratic politicians and mainstream press pundits to accuse it of being in favor of white supremacy is more than just absurd, it is a lie and slander.

The problem I have is that I try to be a decent human being. I don’t like to give these liars and slanderers a platform to spread their hateful lies. In fact, I don’t even wish to read or discuss their childish and mean-spirited behavior. Thus, I have posted nothing until now about the mass murders that occurred this past weekend and the reactions to them.
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Crater on the Basement of Mars

12:05 pm

Crater in the bottom of Hellas Basin
Click for full image.

Cool image time! In the July release of images from the high resolution camera of Mars Reconnaissance Orbiter (MRO) was the image to the right, cropped to post here, showing what I suspect is a relatively young crater located in the lowest part of Hellas Basin, what I call the bottom of Mars.

Though this crater is not located at the lowest point in Hellas, it is not far off from there. What makes it important to geologists are two facts. First, there are not a lot of craters in Hellas, which helps indicate it is a relatively young feature. Second, and more important, the impact has made accessible material from below the surface, indicated by the different colors in this image. From this information they can better constrain their theories about the Basin’s formation and where it fits in Mars’s overall geological history.

Make sure you take a look at the full photograph by clicking of the image, and compare it with the earlier Hellas Basin images I posted here. The surface of Hellas appears to have a lot of flow features, as if it was laid down by volcanic activity, or by the motion of water that covered it. In either case that would explain the overall lack of craters.

0 comments

FCC streamlines and cuts fees for smallsat licensing

9:09 am

Capitalism in space: In an effort to ease its bureaucratic obstacles to private enterprise, the FCC has streamlined its licensing process for new smallsats, while cutting its licensing fees by more than 90%.

Under the optional licensing regime, which stands to take effect this year, smallsat operators with spacecraft that meet certain criteria will be able to obtain a spectrum license about twice as fast and pay only $30,000 instead of nearly $500,000. A maximum of 10 satellites at a time can be licensed under the streamline process.

…Operators will be able to use the streamlined licensing for satellites that weigh 180 kilograms or less, operate below 600 kilometers (or have propulsion) and will deorbit within six years, among other criteria.

One component of these new regulations is that they require new smallsats to never be smaller than 10 centimeters on their smallest dimension, thus essentially forbidding the launch of nanosats smaller than that.

3 comments

Video of Long March 2C grid fins used in July

9:01 am

China Central Television has released a very short video showing the grid fins used during the July 26 launch of China’s Long March 2C rocket in order to better control the descent of that rocket’s expendable first stage.

I have embedded the video below the fold. It shows the four grid fins unfolding, but not much else. It also reveals that the Chinese very clearly were inspired by SpaceX’s Falcon 9 grid fin design.

The video also gives me the impression that the Long March 2C first stage does not have any thrusters, which were SpaceX’s primary mode for controlling its first stages, the grid fins added later when they understood better the engineering required. Thus I suspect that the fins were not very successful in controlling that stage’s flight.

Nonetheless, the Chinese are doing these tests during operations, which means they are only a first step on a path to success.
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Vector gets Air Force launch contract

8:50 am

Capitalism in space: Vector has signed its first Air Force launch contract for an orbital cubesat launch in 2021.

The Air Force must know something about Vector’s rocket development that we don’t. The company had planned a suborbital test launch for March/April, delayed it until June, and has still not flown it. These delays put the company behind its original launch schedule by a considerable amount, which originally had called for its first orbital launch in 2018.

Hopefully we shall soon see some actually progress from Vector. At the moment however their lack of launches has allowed a number of other smallsat rocket companies to gain on them from behind.

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Yutu-2 and Chang’e-4 go to sleep again

8:42 am

Yutu-2's travels

Both Yutu-2 and Chang’e-4 have been put in dormant mode after completing their eighth lunar day on the far side of the Moon.

The article at the link provides a lot of new details about what both spacecraft have learned and done since they landed, including a nice detailed map showing Yutu-2’s exact path during those eight lunar days. The image to the right, reduced to post here, was taken by Yutu-2, and shows the rover’s tracks during what appears to be its seventh lunar day. It appears that the rover periodically stopped and did a pirouette, probably to obtain a 360 degree mosaic of the surrounding terrain.

Yutu-2’s travels have tended west from Chang’e-4, and on its eighth lunar day it continues that route, traveling 271 meters. After a period of short traveling days, they have now upped the distance traversed by a considerable amount. Since the planned nominal mission for both spacecraft had been three lunar days, both are demonstrating that the Chinese have figured out how to do this, and are now pushing Yutu-2 hard as a result.

The article vaguely describes some of the science obtained so far, but in general the Chinese remain tight-lipped about most of their discoveries.

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ULA’s Atlas 5 launches military communications satellite

8:07 am

Early this morning ULA used its Atlas 5 rocket to successfully launch an Air Force military communications satellite.

This was the third ULA launch this year, which means they remain off the leader board below. This number of launches is also below the pace set the last two years, where they completed eight launches per year.

The leaders in the 2019 launch race:

12 Russia
11 China
10 SpaceX
6 Europe (Arianespace)
4 India

The U.S. now leads in the national rankings 17 to 12.

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