Tag: science

Further explorations at candidate Starship Mars landing site

4:02 pm

Beginning of Possible Glacial Unit near candidate Starship landing sites
Click for full image.

Close-up on exposed lower layer

Cool image time! Even though it appears that SpaceX has completed its first round of images of its candidate landing sites surrounding the Erebus Montes mountains in the Arcadia Planitia plains in the Martian northern lowlands, this does not mean that other planetary scientists are not asking for more images of this region, for their own scientific research.

The photograph on the right, cropped and reduced to post here, was released in the early November image download from the high resolution camera of Mars Reconnaissance Orbiter (MRO). Uncaptioned but dubbed “Beginning of Possible Glacial Unit,” it shows what appears at first glance to be a relatively featureless area south of Erebus Montes, out in the flat plains.

A closer look suggests otherwise. For one, the full image shows darker and lighter areas. The close-up to the right, its location indicated by the white box in the wider image above, also shows several intriguing depressions that appear to be revealing a knobby lower layer. In fact, in the full image it appears that the darker areas are areas where material has covered that knobby lower layer. Where it is bright the ground resembles the floors of these depressions, knobby and complex.

I do not know why they label this the “beginning” of a glacial unit. What I do know is that the research of this region has consistently found evidence of a lot of buried ice. To quote Donna Viola of the University of Arizona noted, “I think you could dig anywhere to get your water ice.” The knobby features to me suggest a surface that is showing signs of sublimation, where the exposed ice is slowly eroding. Think of what happens to a block of ice when you spray warm water on it. As it melts it leaves behind just these kinds of strange formations.

Overview of all MRO images at Starship candidate landing site

The red box in the map on the right shows the location of this photograph relative to the other images taken for SpaceX. The white boxes are the company’s images taken for Starship. The black boxes are the images it obtained in 2017 when it was thinking of sending a Dragon capsule to Mars.

This map does not show all images taken by MRO’s high resolution camera in this area, but the coverage is very scattered, with many gaps. Over time I suspect these gaps will be filled more quickly than other northern plain regions, because the scientists know that SpaceX has an interest in this area. That interest means there is an increased chance that a mission will fly here in the relatively near future, which in turn is going to generate more scientific interest as well.

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Does zero gravity cause intestinal issues?

9:23 am

The uncertainties of science: New research simulating microgravity on Earth now suggests that zero gravity might weaken the walls of the intestines.

The barrier function of the intestinal epithelium, he added, is critical for maintaining a healthy intestine; when disrupted, it can lead to increased permeability or leakiness. This, in turn, can greatly increase the risk of infections and chronic inflammatory conditions such as inflammatory bowel disease, celiac disease, Type 1 diabetes, and liver disease.

McCole’s team used a rotating wall vessel — a bioreactor that maintains cells in a controlled rotation environment that simulates near weightlessness — to examine the impact of simulated microgravity on cultured intestinal epithelial cells.

Following culture for 18 days in the vessel, the team discovered intestinal epithelial cells showed delayed formation of “tight junctions,” which are junctions that connect individual epithelial cells and are necessary for maintaining impermeability. The rotating wall vessel also produces an altered pattern of tight junction assembly that is retained up to 14 days after the intestinal epithelial cells were removed from the vessel.

This is good research, but it has not proved anything, merely indicated an area of research that needs a follow-up in space. I also wonder if there has been any evidence of this phenomenon from astronauts returning from long missions. As far as I know, intestinal issues have never been mentioned as a problem post flight.

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New image of Comet 2I/Borisov

1:22 pm

Comet 2I/Borisov
Click for full image.

Astronomers have taken a new image of the interstellar comet 2I/Borisov. The photograph to the right is that image, with the Earth placed alongside to show scale.

According to van Dokkum the comet’s tail, shown in the new image, is nearly 100,000 miles long, which is 14 times the size of Earth. “It’s humbling to realize how small Earth is next to this visitor from another solar system,” van Dokkum said.

Laughlin noted that 2l/Borisov is evaporating as it gets closer to Earth, releasing gas and fine dust in its tail. “Astronomers are taking advantage of Borisov’s visit, using telescopes such as Keck to obtain information about the building blocks of planets in systems other than our own,” Laughlin said.

The solid nucleus of the comet is only about a mile wide. As it began reacting to the Sun’s warming effect, the comet has taken on a “ghostly” appearance, the researchers said.

The comet will reach its closest point to the Earth, 190 million miles, in early December.

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First detection of extended galactic magnetic field

9:51 am

Whale galaxy with magnetic filaments
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Astronomers have made the first detection in another galaxy of a magnetic field that extends out into the galaxy’s halo.

The image above, based on data from the Jansky radio telescope, illustrates what they found..

The spiral galaxy is seen edge-on, with its disk of stars shown in pink. The filaments, shown in green and blue, extend beyond the disk into the galaxy’s extended halo. Green indicates filaments with their magnetic field pointing roughly toward us and blue with the field pointing away. This phenomenon, with the field alternating in direction, has never before been seen in the halo of a galaxy.

“This is the first time that we have clearly detected what astronomers call large-scale, coherent, magnetic fields far in the halo of a spiral galaxy, with the field lines aligned in the same direction over distances of a thousand light-years. We even see a regular pattern of this organized field changing direction,” said Marita Krause, of the Max-Planck Institute for Radioastronomy in Bonn, Germany.

The galaxy, dubbed the Whale by the astronomers, is about 35 million light years away, and has a diameter of about 80,000 light years, slightly smaller than the Milky Way.

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Astronomers find 19 more galaxies showing lack of dark matter

9:11 am

The uncertainty of science: Astronomers have discovered 19 more dwarf galaxies, now totaling 23, that appear to have significant deficits of dark matter.

Of 324 dwarf galaxies analyzed, 19 appear to be missing similarly large stores of dark matter. Those 19 are all within about 500 million light-years of Earth, and five are in or near other groups of galaxies. In those cases, the researchers note, perhaps their galactic neighbors have somehow siphoned off their dark matter. But the remaining 14 are far from other galaxies. Either these oddballs were born different, or some internal machinations such as exploding stars have upset their balance of dark matter and everyday matter, or baryons.

It may not be a case of missing dark matter, says James Bullock, an astrophysicist at the University of California, Irvine. Instead, maybe these dwarf galaxies have clung to their normal matter — or even stolen some — and so “have too many baryons.” Either way, he says, “this is telling us something about the diversity of galaxy formation…. Exactly what that’s telling us, that’s the trick.”

Since we do not know what dark matter is to begin with, finding galaxies lacking it only makes more difficult to create a theory to explain it. Something causes most galaxies to rotate faster than they should, based on their visible mass. What that is remains an unknown.

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Supreme Court allows Mann defamation case to proceed

2:01 pm

The Supreme Court today ruled that the defamation suit of global warming activist Michael Mann against the National Review and the Competitive Enterprise Institute can go forward.

On Monday, the Supreme Court denied a petition by the Competitive Enterprise Institute and National Review magazine to rehear and dismiss the defamation lawsuit brought by well-known climate scientist Michael Mann. The Competitive Enterprise Institute and National Review have been fighting for years to dismiss the case before it goes to trial, but the Supreme Court’s denial means the case will move forward in D.C. district court.

The Supreme Court rejected the petition without comment. But Justice Samuel Alito, a conservative, dissented, arguing that the case addresses critical freedom of speech and freedom of the press issues.

The court has basically ruled that Mann should be allowed his day in court. Since the case stems from criticism of Mann’s shoddy climate science work, I suspect he will find himself having problems once that day arrives, as he did in Canada.

The bad part of this is that it allows Mann to achieve part of his strategy, which is to chill any criticisms of his shoddy work, out of fear he will sue and thus cost the critic a lot of money mounting a defense. No one should be allowed to use the law as a weapon to prevent criticism, especially if that criticism successfully proves the nature of that person’s very shoddy and incompetent climate research, including faking data and hiding pertinent real data.

UPDATE: I have crossed out the words above because they misconstrued my intended meaning. Mann’s effort to use the law to try to squelch opposing points of view is wrong, but in a free society we must allow him this bad behavior. If the law functions properly, his misbehavior (and shoddy science work) will become very evident with time.

By the way, did I mention that Mann’s scientific work is generally very shoddy, and not very trustworthy?

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Mars Express confirms ancient glaciers in northern Martian mid-latitudes

9:46 pm

Perspective view of Deuteronilus Mensae
Click for full image.

The European Space Agency’s orbiter Mars Express has confirmed the presence of large fractured ice sheets suggestive of buried and ancient glaciers. These ice sheets are within one region on Mars located in the mid-latitudes where many such glacial features have been found. They are also in the transition zone between the northern lowlands and the southern highlands.

This landscape shows clear and widespread signs of significant, lasting erosion. As is common with fretted terrain, it contains a mix of cliffs, canyons, scarps, steep-sided and flat-topped mounds (mesa), furrows, fractured ridges and more, a selection of which can be seen dotted across the frame.

These features were created as flowing material dissected the area, cutting through the existing landscape and carving out a web of winding channels. In the case of Deuteronilus Mensae, flowing ice is the most likely culprit. Scientists believe that this terrain has experienced extensive past glacial activity across numerous martian epochs.

It is thought that glaciers slowly but surely ate away at the plains and plateaus that once covered this region, leaving only a scattering of steep, flat, isolated mounds of rock in their wake.

Smooth deposits cover the floor itself, some marked with flow patterns from material slowly moving downhill – a mix of ice and accumulated debris that came together to form and feed viscous, moving flows of mass somewhat akin to a landslide or mudflow here on Earth.

Studies of this region by NASA’s Mars Reconnaissance Orbiter [MRO] have shown that most of the features seen here do indeed contain high levels of water ice. Estimates place the ice content of some glacial features in the region at up to 90%. This suggests that, rather than hosting individual or occasional icy pockets and glaciers, Deuteronilus Mensae may actually represent the remnants of an old regional ice sheet. This ice sheet may once have covered the entire area, lying atop the plateaus and plains. As the martian climate changed this ice began to shift around and disappear, slowly revealing the rock beneath.

Overall, the data coming from both Mars Express and MRO increasingly suggests that there is a lot of buried glacial ice in the mid-latitudes. Mars might be a desert, but it is increasingly beginning to look like much of the planet is a desert like Antarctica, not the Sahara.

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

9:29 pm

Chinese engineers have reactivated both their lunar lander, Chang’e-4, and its rover, Yutu-2, for their twelve lunar day on the far side of the Moon.

The lander woke up at 5:03 p.m. Thursday (Beijing Time), and the rover, Yutu-2 (Jade Rabbit-2), awoke at 0:51 a.m. the same day. Both are in normal working order, according to the Lunar Exploration and Space Program Center of the China National Space Administration.

No word on where Yutu-2 will be sent over then next two weeks.

Posting was light during the day today because Diane and I were on a hike that I needed to do for the upcoming planned second edition of my hiking guidebook, Circuit Hikes of Southern Arizona. My boss (me) allowed me to go, since this hike was not pure pleasure, but reconnaissance for one of my books.

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Unearthly pit in Martian northern icecap

12:24 pm

Giant pit in Martian North polar icecap
Click for full image.

Cool image time! It is spring in the Martian north, and thus the Sun has risen and remains in the sky for most if not all of each day, circling the horizon. As such, it illuminates polar icecap features that are strange and weird and hard to decipher based on our expectations here on Earth.

The photograph to the right, cropped and reduced to post here, is a good example. It was taken on September 20, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO), and shows a pit in the outer regions of the polar icecap, an area where that water icecap remains relatively stable, but that is also at a low enough latitude that summer sunlight can cause some erosion and sublimation of the ice.

The bottom of the pit is the center of the bullseye, with the layered features in the surrounding walls showing the many layers inside the icecap, built up over centuries, then slowly revealed as the ice in this pit slowly sublimated away.

You can get a better sense of what you are looking at by the overview map below.
» Read more

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Astronomers think they have pinned down location of Supernova 1987a’s central star

11:10 am

More than three decades after Supernova 1987a erupted, becoming the first supernova in centuries visible to the naked eye, astronomers finally think they have narrowed the location of the neutron star remaining from that supernova.

Astronomers knew the object must exist but had always struggled to identify its location because of a shroud of obscuring dust. Now, a UK-led team thinks the remnant’s hiding place can be pinpointed from the way it’s been heating up that dust.

The researchers refer to the area of interest as “the blob”. “It’s so much hotter than its surroundings, the blob needs some explanation. It really stands out from its neighbouring dust clumps,” Prof Haley Gomez from Cardiff University told BBC News. “We think it’s being heated by the hot neutron star created in the supernova.”

It will still likely be 50 to 100 years before the dust clears enough for the neutron star itself to be visible.

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Lunar Reconnaissance Orbiter locates crashed Chinese orbiter

9:00 am

Before and after images showing Longjiang-2 impact site

Lunar Reconnaissance Orbiter (LRO) has located the Chinese microsat lunar orbiter Longjiang-2, which was sent to impact the Moon in August 2019 after it completed its technology demonstration mission.

The image above shows the before and after of the location, with the satellite’s remains visible as indicated by the arrow.

Through a careful comparison of pre-existing NAC images, the LROC team was able to locate a new impact crater (16.6956°N, 159.5170°E, ±10 meters), a distance of only 328 meters from the estimated site! The crater is 4 meters by 5 meters in diameter, with the long axis oriented southwest to northeast. Based on proximity to estimated crash coordinates and the crater size, we are fairly confident that this new crater formed as a result of the Longjiang-2 impact.

The picture of the impact site might not be very impressive, but remember, this satellite only weighed about a hundred pounds. The engineering however is impressive, on all counts. First, the Chinese built a tiny cubesat that reached lunar orbit and operated there for more than a year, during which it even took a picture of the Earth. Second, the engineering team of LRO was able to find this tiny impact site for such small spacecraft in less than four months.

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First global geologic map of Titan

11:43 am

Global geologic map of Titan
Click for full image.

Planetary scientists today released the first global geologic map of the Saturn moon Titan. The image on the right is a reduced version of the full image.

In the annotated figure, the map is labeled with several of the named surface features. Also located is the landing site of the European Space Agency’s (ESA) Huygens Probe, part of NASA’s Cassini mission.

The map legend colors represent the broad types of geologic units found on Titan: plains (broad, relatively flat regions), labyrinth (tectonically disrupted regions often containing fluvial channels), hummocky (hilly, with some mountains), dunes (mostly linear dunes, produced by winds in Titan’s atmosphere), craters (formed by impacts) and lakes (regions now or previously filled with liquid methane or ethane).

To put it mildly, there is a lot of uncertainty here. Nonetheless, this is a first attempt, and it shows us that the distribution of these features is not homogeneous. The dunes favor the equatorial regions, the lakes the polar regions. Also, the small number of craters could be a feature of erosion processes from the planet’s active atmosphere, or simply be because Cassini’s radar data did not have the resolution to see smaller craters. I suspect the former.

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Islands of ice on Mars and Pluto

12:54 pm

Ice-filled craters near Martian south pole

In a paper published today in the Journal of Geophysical Research: Planets, scientists describe the identification of 31 ice-filled craters in the high southern latitudes of Mars. The map to the right, from their paper, shows the locations of these craters. The scientists also took a look at Pluto, and found five craters there that had similar features, though these were likely filled with frozen nitrogen, not water ice.

From their abstract:

These new 31 ice deposits represent an inventory of more than 10 trillion cubic meters of solid water, similar to but greater in number and volume than previously studied features near the north pole. Similar features of nitrogen ice may exist in craters on Pluto, suggesting that craters are a favorable location for the accumulation or preservation of ices throughout the Solar System. [emphasis mine]

These results are reinforced by the existence of glacial features found in numerous Martian craters at much lower latitudes, as well as the ice suspected to exist in the permanently shadowed craters on the Moon and Mercury. The processes that put the ice there on these different planets might be fundamentally different, but the results are the same: Ice accumulating within craters.

One aspect of these high latitude craters that remains somewhat unexplained is their asymmetrical distribution around the south pole, favoring the side of the planet south of Mars’ giant volcanoes. Moreover, in looking at the ice deposits within these craters the scientists found that the ice seemed to lie off-center within the craters, favoring a similar direction.

Based on the available data, the scientists theorize that the most likely cause of this asymmetric off-center pattern is wind. From their paper:

Basic physical arguments, mesoscale atmospheric models, and geomorphological observations predict deflection of winds emanating from the south pole by the Coriolis Force. Such deflection results in a general westward trend of winds (i.e., easterlies) in the south polar regions outside the [south pole cap], matching the [ice-filled crater] offsets we observe.

This correlation implies that wind is important in … formation and/or evolution [of craters with ice]. For the case where winds control [their] formation, katabatic winds may travel down the east side of crater walls and preferentially deposit ice on the west side of the crater via orographic precipitation as they flow up the west crater wall. This mechanism thus favors local accumulation of ice within craters.

I find it fascinating that the location of ice within craters on Mars might indirectly provide scientists with information about the planet’s global weather patterns. This unexpected connection highlights the need to dismiss no data or feature in trying to understand planetary formation. Unlikely things might answer our questions.

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The dance of two Neptunian moons

1:26 pm

Scientists have discovered that the orbital interplay between two of Neptune’s moon keep them close together but never touching. Instead, they dance about each other.

In this perpetual choreography, Naiad swirls around the ice giant every seven hours, while Thalassa, on the outside track, takes seven and a half hours. An observer sitting on Thalassa would see Naiad in an orbit that varies wildly in a zigzag pattern, passing by twice from above and then twice from below. This up, up, down, down pattern repeats every time Naiad gains four laps on Thalassa.

Although the dance may appear odd, it keeps the orbits stable, researchers said.

I have embedded below the fold a video that illustrates this.

» Read more

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A journey into the depths of Valles Marineris

1:20 pm

Valles Marineris

Cool image time! Rather than start with the cool image, let’s begin with the long view. To the right is a wide mosaic of Valles Marineris on Mars, the largest known canyon in the solar system. About 2,500 miles long and 400 miles wide, this canyon is so large that it would cover most of the United States if put on Earth. The Grand Canyon, 500 miles long by 19 miles wide, could easily fit within it and not be noticed. In depth Valles Marineris is equally impressive, with a depth of more than four miles, about four times deeper than the Grand Canyon.

A closer view of the central regions of Valles Marineris

The white cross in the mosaic above is where we are heading. You can see it as the white box in the zoomed in overview to the right. This central part of Valles Marineris is named East Melas Chasma, and the red boxes indicate locations where the high resolution camera of Mars Reconnaissance Orbiter (MRO) has already taken images.

As you can see, we do not yet have many high resolution images of this part of the canyon floor. The white box is the most recent image, and is the subject of today’s post.
» Read more

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Upcoming big satellite constellations vex and worry astronomers

10:33 am

Astronomers are expressing increasing distress over the possible negative consequences to their Earth-based telescope observations from the several new giant satellite constellations being launched by SpaceX and others.

[M]any astronomers worry that such ‘megaconstellations’ — which are also planned by other companies that could launch tens of thousands of satellites in the coming years — might interfere with crucial observations of the Universe. They fear that megaconstellations could disrupt radio frequencies used for astronomical observation, create bright streaks in the night sky and increase congestion in orbit, raising the risk of collisions.

The Nature article then details the issues faced by some specific telescopes. Hidden within the article however was this interesting tidbit that admitted the problem for many telescopes is really not significant.

Within the next year or so, SpaceX plans to launch an initial set of 1,584 Starlink satellites into 550-kilometre-high orbits. At a site like Cerro Tololo, Chile, which hosts several major telescopes, six to nine of these satellites would be visible for about an hour before dark and after dawn each night, Seitzer has calculated.

Most telescopes can deal with that, says Olivier Hainaut, an astronomer at the European Southern Observatory (ESO) in Garching, Germany. Even if more companies launch megaconstellations, many astronomers might still be okay, he says. Hainaut has calculated that if 27,000 new satellites are launched, then ESO’s telescopes in Chile would lose about 0.8% of their long-exposure observing time near dusk and dawn. “Normally, we don’t do long exposures during twilight,” he says. “We are pretty sure it won’t be a problem for us.” [emphasis mine]

The article then proceeds with its Chicken-Little spin as if the astronomical world is about to end if something is not done to stop or more tightly control these new satellite constellations.

As indicated by the quote above, it appears however that the threat is overstated. The constellations might reduce observing time slightly on LSST, scheduled for completion in 2022 and designed to take full sky images once every three nights. Also, the satellite radio signals might impact some radio astronomy. In both cases, however, the fears seem exaggerated. Radio frequencies are well regulated, and LSST’s data should easily be able to separate out the satellite tracks from the real astronomical data.

Rather than demand some limits or controls on this new satellite technology, the astronomical community should rise to the occasion and find ways to overcome this new challenge. The most obvious solution is to shift the construction of new telescopes from ground-based to space-based. In fact, this same new satellite technology should make it possible for them to do so, at much less cost and relatively quickly.

But then, astronomers are part of our modern academic community, whose culture is routinely leftist and therefore fascist in philosophy (even though they usually don’t realize it). To them too often the knee-jerk response to any competition is to try to control and squelch it.

We shall see if the astronomers succeed in this case.

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Both methane and oxygen fluctuate in unison seasonally in Gale Crater

10:04 am

The uncertainty of science: According to a new science paper, data from Curiosity on Mars has now found that both methane and oxygen fluctuate in unison seasonally in Gale Crater.

From the paper’s abstract:

[T]he annual average composition in Gale Crater was measured as 95.1% carbon dioxide, 2.59% nitrogen, 1.94% argon, 0.161% oxygen, and 0.058% carbon monoxide. However, the abundances of some of these gases were observed to vary up to 40% throughout the year due to the seasonal cycle. Nitrogen and argon follow the pressure changes, but with a delay, indicating that transport of the atmosphere from pole to pole occurs on faster timescales than mixing of the components. Oxygen has been observed to show significant seasonal and year‐to‐year variability, suggesting an unknown atmospheric or surface process at work. These data can be used to better understand how the surface and atmosphere interact as we search for signs of habitability.

The data shows that the unexpected and so far unexplained seasonal oxygen fluctuation appears to track the same seasonal methane fluctuations. While biology could cause this signature, so could geological processes, though neither can produce these fluctuations easily.

Meanwhile, adding to the uncertainty were results from the two European orbiters, Mars Express and Trace Gas Orbiter. Both have failed to detect a June 19, 2019 dramatic spike in methane that had been measured by Curiosity.

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China unveils Mars lander during landing simulation test

9:44 am

The new colonial movement: China today unveiled to the international press its first prototype Mars lander, showing it attempting a simulated controlled descent on a gigantic test stand.

The demonstration of hovering, obstacle avoidance and deceleration capabilities was conducted at a site outside Beijing simulating conditions on the Red Planet, where the pull of gravity is about one-third that of Earth.

China plans to launch a lander and rover to Mars next year to explore parts of the planet in detail.

This is the first time I have heard anything about China sending a lander/rover to Mars in 2020. Previously the reports had discussed only sending an orbiter.

I have embedded video of the test below the fold. It shows the prototype hanging by many wires from the test stand, then dropping quickly, with its engine firing, before stopping suddenly, followed by an engine burst. While impressive, it did not strike me that China is even close to sending this spacecraft to Mars. The test only proved the spacecraft’s ability to do some maneuvering during descent. It did not show that it could land.

That the project’s designer said that landing would take “about seven minutes” also suggests that they are copying the techniques used by JPL to land Curiosity. Considering that JPL’s computers have been repeatedly hacked, including some hacks identified as coming from China, it would not surprise me if China has simply stolen those techniques.

I still expect them to launch an orbiter to Mars in 2020. Whether they also send a lander and rover remains to be seen.
» Read more

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Hayabusa-2 begins journey back to Earth

9:32 am

The Hayabusa-2 science team has fired up the spacecraft’s ion engine to leave the asteroid Ryugu and began its begins journey back to Earth.

It will take about six days to exit the gravitational sphere of influence of Ryugu. During that time period they will be continually releasing real time images of the asteroid from the spacecraft’s navigation camera, as it slowly gets farther away.

In mid-December they will fire the spacecraft’s main engines for an arrival near Earth in late 2020. At that point the small return capsule holding the samples from Ryugu will separate and land in the Australian desert. Hayabusa-2, still operational, might then be given a new subsequent mission.

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Parker releases first data to public

9:10 am

The solar wind as seen from Parker
Click for full image.

Having completed its first three orbits of the Sun, the Parker Solar Probe science team today made all the data obtained available to the public.

The image to the right was taken during the first close solar flyby in November 2018. It shows solar wind particles streaming past the spacecraft.

Do not expect many spectacular images from Parker. It has a camera, but the mission’s focus is the study of the Sun’s atmosphere and solar wind, neither of which are likely to be very photogenic.

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Polygons on Mars

1:44 pm

Scallops and polygons on Mars
Click for full image.

Cool image time! The photograph on the right, cropped to post here, was taken on September 25, 2019 by the high resolution camera on Mars Reconnaissance Orbiter (MRO) and made public in its November image release. It shows the weird but very typical scalloped terrain, with its adjacent polygon pattern of fractures, found routinely in the northern lowland plains of Utopia Planitia on Mars. From an earlier captioned image from 2006 of these same features:

The scalloped depressions are typical features; a smooth layered terrain located between 40 and 60 degrees in both hemispheres. Scalloped depressions probably form by removal of ice-rich subsurface material by sublimation (ice transforming directly from a solid to a gaseous state), a process that may still be active today. Isolated scalloped depressions generally have a steep pole-facing scarp and a gentler equator-facing slope. This asymmetry is interpreted as being the result of difference in solar heating. Scalloped depressions may coalesce, leading to the formation of large areas of pitted terrain.

The polygonal pattern of fractures resembles permafrost polygons that form in terrestrial polar and high alpine regions by seasonal-to-annual contraction of the permafrost (permanently frozen ground). On Earth, such polygons indicate the presence of ground ice.

On Earth these polygons are most often seen in mud, usually suggesting a drying process where the ground contracts with the lose of fluid. On Mars the cracks probably also form from contraction, but not by the lose of fluid but the lose of water ice as it sublimates into a gas.

These polygons and scallops illustrate an important feature of Mars’ vast northern plains. On large scales these plains appear flat and featureless. Up close however many many strange features, like the polygons and scallops in this image, come into view.
» Read more

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New Horizons team renames “Ultima Thule” to “Arrokoth”

12:57 pm

The New Horizons team has renamed the Kuiper Belt object that the spacecraft flew past on January 1, 2019 from its informal nickname of “Ultima Thule” to “Arrokoth,” which means “sky” in Powhatan/Algonquian language.

This official, and very politically correct, name has apparently gotten the stamp of approval from the IAU.

In accordance with IAU naming conventions, the discovery team earned the privilege of selecting a permanent name for the celestial body. The team used this convention to associate the culture of the native peoples who lived in the region where the object was discovered; in this case, both the Hubble Space Telescope (at the Space Telescope Science Institute) and the New Horizons mission (at the Johns Hopkins Applied Physics Laboratory) are operated out of Maryland — a tie to the significance of the Chesapeake Bay region to the Powhatan people.

“We graciously accept this gift from the Powhatan people,” said Lori Glaze, director of NASA’s Planetary Science Division. “Bestowing the name Arrokoth signifies the strength and endurance of the indigenous Algonquian people of the Chesapeake region. Their heritage continues to be a guiding light for all who search for meaning and understanding of the origins of the universe and the celestial connection of humanity.” [emphasis mine]

It is a good name, especially because its pronunciation is straight-forward, unlike the nickname.

The blather from Glaze above, however, is quite disingenuous. The Algonquian people have had literally nothing to do with the modern scientific quest for “meaning and understanding of the origins of the unverse.” They were a stone-age culture, with no written language. It was western civilization that has made their present lives far better. And it was the heritage of western civilization, not “the indigenous Algonquian people” that made the New Horizons’ journey possible. Without the demand for knowledge and truth, as demanded by western civilization, we would still not know that Arrokoth even existed.

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Astronomers discover star fleeing Milky Way at 3.7 million mph

12:46 pm

Astronomers have discovered a star that rocketing out of the Milky Way at 3.7 million miles per hour because five million years ago it made a close approach to Sagittarius A* (prounounced “A-star”), the super-massive black at the center of the galaxy.

“The velocity of the discovered star is so high that it will inevitably leave the Galaxy and never return”, said Douglas Boubert from the University of Oxford, a co-author on the study.

Astronomers have wondered about high velocity stars since their discovery only two decades ago. S5-HVS1 is unprecedented due to its high speed and close passage to the Earth, “only” 29 thousand light years away. With this information, astronomers could track its journey back into the centre of the Milky Way, where a 4 million solar mass black hole, known as Sagittarius A*, lurks.

Almost certainly there are many such stars. They are just hard to spot.

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Hayabusa-2 to begin return voyage on November 13

8:08 am

In a press conference today the science team for the asteroid probe Hayabusa-2 announced that the spacecraft will begin the first stage of its journey back to Earth tomorrow, using its ion engine to slowly pull away from Ryugu.

That first stage will take a little less than a week. Once the spacecraft gets about 25 miles from Ryugu it will leave its sphere of gravitational influence, when it will then begin its cruise phase back to Earth.

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Mars’ seasonally vanishing carbon dioxide polar cap

1:36 pm

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

Since the onset of the Martian spring in the northern hemisphere back in March of this year, scientists have been busy using the high resolution camera on Mars Reconnaissance Orbiter (MRO) to monitor the expected sublimation and disappearance of the cap of dry ice that falls as snow to become a winter layer mantling both the more permanent icecap of water 7,000 feet deep as well as the giant dune sand seas that surround that northern icecap.

The image on the right was first posted here on Behind the Black on June 6, 2019 as part of a long article describing that northern polar icecap and its annual evolution. It shows a set of dunes that Candice Hansen of the Planetary Science Institute in Arizona, who requested the image, has dubbed “Buzzell.” When that picture was taken in March, the frozen dry ice layer of translucent carbon dioxide still coated the dunes. The image’s darkness is because the Sun has just begun to rise above the horizon at this very high latitude location (84 degrees). The circular feature is likely a buried ancient crater, with the streaks indicating the prevailing wind direction blowing both sand and frost about.

On August 9, 2019 I provided an update on this monitoring, when new images of this same location were downloaded from MRO in April and June. MRO has now taken a new image of Buzzell, on October 2, 2019. Below the fold are all these images so that you can see the sublimation and disappearance of that dry ice layer over time.
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We are not going to die from climate change

12:20 pm

Tony Heller today published this quite thorough review of the failed climate predictions by global warming scientists/activists, while also providing a great summary of the real state of our climate.

You can disagree or question him on one point or another, but the overall data once again illustrates the uncertainty that surrounds climate science. We really do not know what is going on, and any predictions that claim we do are hogwash.

Above all, take a look at the section on the benefits of increased CO2 in the atmosphere. This data is widespread and robust, and has been confirmed by agriculturists for decades. The planet is getting greener and as a result more fertile as there has been an increase in atmospheric CO2.

Meanwhile, the fear-mongers insist the world will end in just over eleven years, based not on any real data but on their emotional desire for catastrophe.

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Bennu & Ryugu: Two very old and strange asteroids

5:35 pm

Bennu as seen by OSIRIS-REx
Bennu’s equatorial ridge. Click for full image.

This week the science team operating the OSIRIS-REx spacecraft at the asteroid Bennu hosted a joint conference in Tucson, Arizona, with the scientists operating the Hayabusa-2 spacecraft at the asteroid Ryugu. Both gave up-to-date reports on the science so far obtained, as well as outlined upcoming events. I was fortunate enough to attend.

First an overview. Both Bennu and Ryugu are near earth asteroids, with Bennu having an orbit that might even have it hit the Earth in the last quarter of 2100s. Both are very dark, and are rubble piles. Both were thought to be of the carbonaceous chondrite family of asteroids, sometimes referred to as C-type asteroids. This family, making up about 75% of all asteroids, includes a bewildering collection of subtypes (B-types, F-types, G-types, CI, CM, CV, CH, CB, etc), all of which were initially thought to hold a lot of carbon. We now know that only a few of these categories, the CI and CM for example, are carbon rich.

Even so, we actually know very little about these types of asteroids. They are very fragile, so that any that reach the Earth’s surface are not a good selection of what exists. About 90% of the material gets destroyed in the atmosphere, with the remnant generally coming from the innermost core or more robust nodules. We therefore have a biased and limited sample.

It is therefore not surprising that the scientists are finding that neither Bennu nor Ryugu resembles anything else they have ever seen. Both have aspects that resemble certain types of carbonaceous chondrite asteroids, but neither provides a very good fit for anything.
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Watch the Mercury transit of the Sun from home!

3:33 pm

The November 11 transit of Mercury across the face the Sun will be live streamed by the Griffith Observatory in Los Angeles.

It appears that in Los Angeles the transit will have already started at sunrise, with Mercury at that point about a third of its way across the Sun’s face. Regardless, from about 7 am to 10 am (Pacific) the observatory will provide a view.

UPDATE: Images from an event in New Zealand will upload real time telescope images of the transit here.

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New InSight image of mole shows collapse of hole

10:56 am

View of InSight drill hole
Click for full movie.

The InSight science image has lifted the lander’s rover arm off the drill hole and taken a new series of images in an effort to discover what caused the mole to pop out during its most recent drilling effort.

The image to the right, cropped to post here, was the first in a short movie made from all the images taken over the course of a day. The sequence shows the change in shadows, which helps define the situation in the hole.

This image however I think tells all. It shows that the walls of the hole have collapsed all around the mole, widening it further. It also shows that, once the mole popped out to lean sideways against the left wall, much of that material then fell into the hole, refilling it. These facts are very evident when today’s image is compared with this image from October, taken prior to the most recent drilling effort. The hole has become much wider, there is more material inside it, and the mole is now much farther out.

All these facts bode ill for the mole ever succeeding in drilling down the planned fifteen or so feet to insert a heat probe into the interior of Mars in order to take the first ever measure of the planet’s interior.

An overall assessment of this NASA mission is not very positive. The contribution from its international partners is especially bad. The mission was launched two years late because the French effort to build the seismometer failed. NASA had to subsequently give the job to JPL to get it done. Now the heat sensor is a failure, because the German-built mole has failed to get the heat sensor where it needs to be.

The seismometer and heat sensor were InSight’s only science instruments. This means that we will likely only get results from one.

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