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« Reply #2160 on: Nov 26, 2019, 04:40 AM »

Buckyballs in space: how complex carbon molecules form in space

The mystery of how complex carbon molecules--buckyballs-- came to be detected in interstellar space may have been solved.

Rob Lea
ZME
11/26/2019

The mystery of how complex carbon molecules with a ‘soccer-ball’ type structure–nicknamed buckyballs–came to be found in interstellar space has puzzled scientists for some time.

But now, a team of researchers from the University of Arizona have proposed a potential formation mechanism for carbon-60 (C60)–a spherical molecule comprised of 60 carbon atoms in ring-like structures–in space.

The team discovered that silicon carbide dust left behind by dying stars then bombarded by high energy particles and extreme temperatures could shed silicates leaving behind pure carbon needed to create C60.

Their results are published in the journal Astrophysical Journal Letters.

The detection of buckyballs–named for their similarity to the dome-like architecture of Buckminister Fuller– and even larger C70 molecules a few years ago caused a rethink of the theory that such molecules could only be formed in the lab.

Additionally, and more importantly, the discovery overturned the idea that only light molecules–up to around 10 atoms–could be found scattered through interstellar space.

Another surprise emerged from the fact that the molecules detected were pure carbon.

In the lab, C60 is created by blasting together pure carbons sources such as graphite. This process should be almost impossible in the planetary nebulae that the interstellar C60 was found. This is because this environment– debris created in the violent death throes of stars–has about 10,000 hydrogen molecules for every carbon molecule.

    “Any hydrogen should destroy fullerene synthesis,” says Jacob Bernal, an astrobiology and chemistry doctoral student and lead author of the paper. “If you have a box of balls, and for every 10,000 hydrogen balls you have one carbon, and you keep shaking them, how likely is it that you get 60 carbons to stick together?

    “It’s very unlikely.”

Bernal and his team began investigating this conundrum with the aim of uncovering a potential C60 formation mechanism when they realised that the transmission electron microscope (TEM) located at the Kuiper Materials Imaging and Characterization Facility at the University of Arizona, was able to simulate the planetary nebula environment fairly well.

TEM’s 200,000-volt electron beam is able to probe matter down to 78 picometers in order to see individual atoms. The beam also operates in a vacuum with extremely low pressures. The incredibly low-pressure in TEM is very close to the pressure found in circumstellar environments. But this is more by luck than design.

    “It’s not that we necessarily tailored the instrument to have these specific kinds of pressures,” explains study co-author Tom Zega, an associate professor in the Univerity of Arizona Lunar and Planetary Lab. “These instruments operate at those kinds of very low pressures not because we want them to be like stars, but because molecules of the atmosphere get in the way when you’re trying to do high-resolution imaging with electron microscopes.”

The team drafted the assistance of the U.S. Department of Energy’s Argonne National Lab, Chicago, which has a TEM capable of studying the radiation responses of materials. Placing silicon carbide–a common form of dust produced by stars– in the low-pressure environment of the TEM, the team in Chicago subjected it to temperatures up to 1,830 degrees Fahrenheit whilst bombarding it with high-energy xenon ions.

Tom Zega at the control panel of the 12-foot tall transmission electron microscope at the Kuiper Materials Imaging and Characterization Facility at the UArizona Lunar and Planetary Lab. The instrument revealed that buckyballs had formed in samples exposed to conditions thought to reflect those in planetary nebulae. Daniel Stolte/University Communications

Following this, the sample was returned to the University of Arizona so researchers could employ the higher resolution and better analytical capabilities of the TEM located there. The team’s hypothesis would be validated if they observed the silicon shedding and exposing pure carbon.

    “Sure enough, the silicon came off, and you were left with layers of carbon in six-membered ring sets called graphite,” adds co-author Lucy Ziurys, Regents Professor of astronomy, chemistry and biochemistry. “And then when the grains had an uneven surface, five-membered and six-membered rings formed and made spherical structures matching the diameter of C60.

    “So, we think we’re seeing C60.”

This work suggests that C60 is derived from the silicon carbide dust made by dying stars–hit by high temperatures, shockwaves and high energy particles. These violent conditions leech silicon from the surface and leaving carbon behind.

These big molecules are dispersed because dying stars eject their material into the interstellar medium – the spaces in between stars – thus accounting for their presence outside of planetary nebulae.

Buckyballs are very stable to radiation, allowing them to survive for billions of years if shielded from the harsh environment of space.

    “The conditions in the universe where we would expect complex things to be destroyed are actually the conditions that create them,” says Bernal, also adding that the implications of the findings are endless.

    “If this mechanism is forming C60, it’s probably forming all kinds of carbon nanostructures,” Ziurys concludes. “And if you read the chemical literature, these are all thought to be synthetic materials only made in the lab, and yet, interstellar space seems to be making them naturally.”

Original research: “Formation of Interstellar C60 from Silicon Carbide Circumstellar Grains,” The Astrophysical Journal Letters, 2019.


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« Reply #2161 on: Nov 27, 2019, 04:44 AM »

Jupiter’s Great Red Spot Isn’t Dead Yet

Pieces of the gas giant’s greatest storm had seemed to be slipping away, but scientists say the underlying vortex is unchanged.

By Kenneth Chang
NY Times
Nov. 26, 2019

Jupiter’s Great Red Spot is shrinking, but that does not necessarily mean that it is dying.

Earlier this year, amateur astronomers caught the red spot seemingly starting to fall apart, with rose-colored clouds breaking away from the storm that is some 15,000 miles wide. In May, giant streamers of gas appeared to be peeling from the spot’s outer rim, blown into the winds circling the planet.

The spot — which is red for reasons not fully understood — has become smaller in recent decades. Some Jupiter-watchers wondered if they were witnessing the beginning of the Great Red Spot’s end.

“We beg to differ with that conclusion,” Philip S. Marcus, a professor of fluid mechanics at the University of California, Berkeley said on Monday during a news conference at a meeting of the American Physical Society’s division of fluid dynamics in Seattle. In essence, Dr. Marcus said, the odd dynamics in the spot are just the result of weather on Jupiter, the solar system’s largest planet.

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Jupiter and Its Moons

Spinnable maps of Jupiter and the Galilean moons: https://www.nytimes.com/interactive/2016/07/01/science/space/jupiter-and-its-moons.html?mtrref=www.nytimes.com&gwh=CC807D5A56AC3573DCFF8ADCBE857BA2&gwt=pay&assetType=REGIWALL

Robert Hooke, an English scientist, first reported an oval on Jupiter in 1664. The following year, Giovanni Cassini, an Italian astronomer, also observed a spot and he and others continued observing it until 1713. (Cassini died in 1712.) Then astronomers lost track of it for more than a century. That could mean Cassini’s spot disappeared and another one formed later, or it could mean that no one was looking carefully during that time. The current spot has persisted for at least 189 years, and probably for centuries before that.

The Great Red Spot is an anticyclone — a high-pressure system that, because it is in the southern hemisphere, rotates in a counterclockwise direction. That makes it unlike hurricanes and other large storms on Earth, which are low-pressure weather systems, or cyclones, that rotate in the opposite direction of anticyclones. Cyclones also exist on Jupiter, but the warm air at the centers of Jovian cyclones often forms wispy clouds, or no clouds at all.

Thus, just looking at the clouds of Jupiter is sometimes misleading, missing the effects of unseen cyclones.

The clouds, at the top of Jupiter’s atmosphere, do not necessarily tell what is going on deep down, hundreds of miles below the Great Red Spot in the vortex that drives the storm.

“You can’t just conclude that if a cloud is getting smaller that the underlying vortex is getting smaller,” he said.

Through computer simulations, Dr. Marcus and his colleagues have been studying the dynamics of the Great Red Spot and other Jovian anticyclones.

The clouds of anticyclones do not always match the boundaries of the underlying vortex. But they also give clues to nearby cyclones.

The simulations indicate a coincidence of two phenomena accounts for the odd dynamics of the Red Spot. Every decade or so, a cyclone comes close to the Great Red Spot and the winds of the two systems collide and deflect at an angle.

“It’s like having two fire hoses aimed at each other,” Dr. Marcus said.

At the same time, the storm was merging with a smaller anticyclone, the deflected winds from the collision with the cyclone carved off pieces of the merging anticyclone. That formed the blade-shaped clouds that were seen separating from the spot, Dr. Marcus said.

He added that the event was just part of the normal dynamics of Jupiter. The Great Red Spot, he predicts, will live “for the indefinite future” — likely centuries longer.

“Of course, I probably just gave it the kiss of death,” Dr. Marcus joked, “and it’ll probably fall apart next week.”


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« Reply #2162 on: Nov 28, 2019, 04:44 AM »

You Could Actually Snooze Your Way Through an Asteroid Belt

By Kenneth Chang
NY Times
11/28/2019

Misconception: In an asteroid belt, spaceships have to dodge a fusillade of oncoming rocks.

Actually: If you were in the middle of an asteroid belt, you probably wouldn’t see any asteroids at all.

A popular game in the early days of video games was Atari’s Asteroids. You would maneuver and spin a small triangular spaceship, blasting space rocks to bits until inevitably one of the asteroids smashes you into line segments. (Magically, the asteroids passed through each other unscathed.)

In space, it seemed, one had to continually dodge destruction. That was true in the “Green Lantern” movie in 2011 and perhaps most memorably in “Star Wars: The Empire Strikes Back.”

With the Millennium Falcon’s hyperdrive conked out and Imperial TIE fighters and star cruisers close in pursuit, Han Solo steers his spacecraft into a thicket of asteroids.
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“You’re not actually going into an asteroid field?” Princess Leia asks.

“They’d be crazy to follow us, wouldn’t they?” Han Solo replies.

C3PO, the fussbudget android, helpfully informs Han, “Sir, the possibility of successfully navigating an asteroid field is approximately 3,720 to 1.” (Statistics pedants point out that C3PO should have said, “approximately one in 3,720.”)

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“Never tell me the odds,” Han says as the Millennium Falcon swerves past giant rocks left and right, top and bottom. One of the TIE fighters goes kaboom, then another.

Of course, that asteroid field was in a galaxy far, far away, but it was still silly. Asteroids — small, rocky chunks that never coalesced into a planet — would not be that close to one another for a simple reason: If they were big enough and close enough to pose a danger to a spaceship, they would also be banging into each other, themselves reduced to tiny pieces.

That bad science inspired J.L. Galache, an astronomer at the International Astronomical Union’s Minor Planet Center in Cambridge, Mass., to figure out just how likely a spacecraft would get hit by an asteroid. In our solar system, most asteroids, perhaps a billion of them 100 meters or wider, can be found in a circular belt between the orbits of Mars and Jupiter.

He calculated for those billion asteroids that are bigger than a football field, there would be just one asteroid per 33 quadrillion cubic miles. That means that in a cube 320,000 miles on a side — that’s a volume equal to some 120,000 Earths — there would be, on average, just one asteroid inside.

NASA takes advantage of this fortunate circumstance every times it sends a spacecraft to the outer solar system.

During nine missions — most recently NASA’s Juno mission on its way to Jupiter, nothing of significance has ever collided with a spacecraft. Of course, there is never a person seated in that spacecraft; the people looking for problems are back on Earth.

S. Alan Stern, the principal investigator for the New Horizons mission to Pluto wrote that when his spacecraft passed through the asteroid belt in 2006, the chance of collision was “almost vanishingly small — far less than one in one billion.”

In other words, one could snooze while flying through the asteroid belt. But that would make for dull movies and easy video games.


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« Reply #2163 on: Nov 29, 2019, 04:45 AM »

It’s official: There’s water on Jupiter’s moon Europa

This is one of the most important findings of the decade

Mihai Andrei
ZME
11/29/2019

NASA has confirmed that Jupiter’s moon Europa contains liquid water, making it one of the most promising places we know for extraterrestrial life.

At first glance, not much is happening on Europa. A small, frozen world orbiting Jupiter doesn’t seem like the most interesting place out there. But 40 years ago, the Voyager snapped an intriguing photo of the satellite: its frozen surface wasn’t stale and monotonous, it was cracked and sliced by different features, suggesting active and recent phenomena. Subsequent missions showed even more exciting things.

Despite being undoubtedly bombarded by meteorites, Europa’s surface is largely devoid of craters. This means that something must have erased or eroded them, suggesting some active geology. Not only is Europa active — it has some form of tectonics, and more impressively, it seems to have liquid water. The liquid water isn’t on the surface but rather beneath the frozen surface. The pattern of the cracks observed on Europa’s surface suggest that the frozen surface of the planet is not locked to the rest of the interior, which is exactly what you’d expect to happen if a layer of liquid were to exist beneath the surface.

To make things even more tantalizing, astronomers have observed something which seems to be plumes of water emerging from Europa. Some of the plumes are hundreds of kilometers high, adding even more evidence to the case for water on Europa.

Now, that case is essentially proven. Researchers looking from the W. M. Keck Observatory, atop the dormant Mauna Kea volcano in Hawaii, found a clear signature of water molecules.

    “Essential chemical elements (carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur) and sources of energy, two of three requirements for life, are found all over the solar system. But the third — liquid water — is somewhat hard to find beyond Earth,” said Lucas Paganini, a NASA planetary scientist who led the water detection investigation. “While scientists have not yet detected liquid water directly, we’ve found the next best thing: water in vapor form.”

Watch: https://www.youtube.com/watch?v=AEyOoZ7JpyY&feature=emb_title

Detecting the signatures of elements on other planets is much more difficult than on Earth. Naturally, Europa’s environment is very different from that of Earth. The main idea behind the study was to use a spectrograph to assess the chemical composition of Europa by measuring how molecules on the satellite interact with infrared light. Molecules such as water emit specific frequencies which can be used as signatures.

But when your telescope is based on Earth, all light would pass through the Earth’s atmosphere — which contains a lot of water on its own. Paganini’s team had to use complex modeling to simulate the conditions of Earth’s atmosphere and then subtract them from what they were seeing on Europa. It wasn’t an easy task, but in the end, the researchers were successful.

Even so, they say, they’d like to get much closer to Europa to see what’s going on.

    “We performed diligent safety checks to remove possible contaminants in ground-based observations,” said Avi Mandell, a Goddard planetary scientist on Paganini’s team. “But, eventually, we’ll have to get closer to Europa to see what’s really going on.”

They’ll get their wish fairly soon. NASA’s Clipper mission is set to launch in 2025, with the objective of analyzing Europa’s habitability and chemistry, as well as its geology. The mission will also aid in the selection of a landing site for the future Europa Lander, which, as the name implies, is scheduled to land on Europa to analyze it in unprecedented detail. Even before that, the ESA’s JUpiter ICy moons Explorer (JUICE) is set to launch in 2022, with the purpose of analyzing Jupiter’s Galilean moons: Ganymede, Callisto, and Europa.

For a period, the two spacecraft will both be orbiting Europa, enabling us to understand the satellite better than ever before. Hopefully, these missions could help answer one of the most tormenting questions in modern astronomy.

Europa, this small frozen rock orbiting Jupiter, has water. Could it have life?


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« Reply #2164 on: Nov 30, 2019, 05:37 AM »

Could wormholes actually exist?

A new study describes a technique that could be used to find wormholes.

Jordan Strickler
ZME
11/30/2019

In the move Interstellar, former NASA pilot Joseph Cooper (Matthew McConaughey) is sent hurtling through time and space via a wormhole in order to save humanity. Essentially, humans have screwed up this planet to the extent that in order to survive, we all have to move to a less-screwed-up planet. The quickest way to this new future home is through a wormhole near Saturn. This opening is the entrance to a distant galaxy located near a black hole named Gargantua. And, of course, if anyone can do it, it’s the bad-ass McConaughey.

Wormholes have always been the fascinating stuff of sci-fi, because come on, intertwining dimensions by bending space and time is pretty cool. Unfortunately, they’ve never been proven to actually exist. Luckily, however, that hasn’t put off scientists from trying. Now a new study out of the University of Buffalo (UB) has attempted to take a look at what they would look like if they were real.

Obviously, the first place you would look for a wormhole would be a black hole or a binary black hole system, which involves two black holes circling one another. Theoretically, the insane amount of gravity would pull them together and create a tunnel.

For their study, the researchers focused on Sagittarius A*, an object that’s thought to be a supermassive black hole at the heart of the Milky Way galaxy. While there’s no evidence of a wormhole there, it’s a good place to look for one because wormholes are expected to require extreme gravitational conditions, such as those present at supermassive black holes.

Black holes are massive pits of gravity that will bend space-time due to their incredibly dense centers, or singularities. When a massive star dies, it collapses inward, and as it does so, the star explodes into a supernova — a catastrophic expulsion of its outer material. This dying star will continue to collapse until it becomes either a neutron star or a singularity — something consisting of zero volume and infinite density. This seemingly impossible contradiction is what causes a black hole to form.

The UB scientists believed that if a wormhole does exist at Sagittarius A, nearby stars would be influenced by the gravity of stars at the other end of the passage. As a result, it would be possible to detect the presence of a wormhole by searching for small deviations in the expected orbit of stars near Sagittarius A.

    “If you have two stars, one on each side of the wormhole, the star on our side should feel the gravitational influence of the star that’s on the other side. The gravitational flux will go through the wormhole,” says Dejan Stojkovic, PhD, cosmologist and professor of physics in UB’s College of Arts and Sciences. “So if you map the expected orbit of a star around Sagittarius A*, you should see deviations from that orbit if there is a wormhole there with a star on the other side.”

The research, which was published in Physical Review D, focuses on how scientists could hunt for a wormhole by looking for perturbations in the path of S2, a star that astronomers have observed orbiting Sagittarius A*.

While current surveying techniques are not yet precise enough to reveal the presence of a wormhole, Stojkovic says that collecting data on S2 over a longer period of time or developing techniques to track its movement more precisely would make such a determination possible. These advancements aren’t too far off, he says, and could happen within one or two decades.

The good doctor cautions, however, that although this new method might be used to detect a wormhole if one is there, it will not strictly prove that a wormhole is present.

    “When we reach the precision needed in our observations, we may be able to say that a wormhole is the most likely explanation if we detect perturbations in the orbit of S2,” he says. “But we cannot say that, ‘Yes, this is definitely a wormhole.’ There could be some other explanation, something else on our side perturbing the motion of this star.”

Wormholes were originally conceived in 1916 by Ludwig Flamm. The Austrian physicist was reviewing another physicist’s solution to the equations in Albert Einstein’s theory of general relativity when he believed another solution might, in fact, be possible. His “white hole” was a theoretical time reversal of a black hole. Entrances to both black and white holes could be connected by a space-time conduit.

Though, if we ever do find one, it probably won’t be the one that science fiction has shown us.

    “Even if a wormhole is traversable, people and spaceships most likely aren’t going to be passing through,” says Stojkovic . “Realistically, you would need a source of negative energy to keep the wormhole open, and we don’t know how to do that. To create a huge wormhole that’s stable, you need some magic.”


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« Reply #2165 on: Dec 02, 2019, 04:36 AM »

Scientists find ‘monster’ black hole so big they didn’t think it was possible

Katie Mettler
WA Post
12/2/2019

Before now, scientists did not think it was possible for a stellar black hole to have a mass larger than 20 times that of the sun, an approximation based on their understanding of the way stars evolve and die in the Milky Way.

But that assumption was metaphorically crushed in the gravity of a “monster” black hole that a group of Chinese-led international scientists discovered inside our own galaxy. The hole has a mass 70 times that of the sun, researchers said in their study published in the journal Nature.

“No one has ever seen a 70-solar-mass stellar black hole anywhere,” Joel Bregman, one of the study authors and a professor of astronomy at the University of Michigan, said in an interview. “This is the first.”

An alien comet from another star is soaring through our solar system

Black holes form when a star runs out of fuel and collapses on itself, creating a strong gravitational pull that prevents anything — even light — from escaping. In the process, those stars lose much of their mass, producing black holes that reflect their diminished size.

The newly discovered black hole, named LB-1 by the team of researchers who published the study, is located 15,000 light-years from earth, according to a news release. And it is huge.

“Black holes of such mass should not even exist in our Galaxy, according to most of the current models of stellar evolution,” Liu Jifeng, a professor at the National Astronomical Observatory of China, said in a news release from the Chinese Academy of Sciences. “… Now theorists will have to take up the challenge of explaining its formation.”

Previously, about two dozen black holes have been discovered and studied in our galaxy using X-ray technology that detects a bright light emitted when a black hole eats a neighboring star. While successful, this process limited scientists’ ability to find more black holes because the vast majority of them in our galaxy are not actively consuming other stars.

LB-1 was discovered by China’s Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST), which has provided scientists with a new way to find the estimated 100 million black holes in the Milky Way. LAMOST enables researchers to detect black holes by first tracking stars that are orbiting something invisible to more than the naked eye, such as a black hole.

When LAMOST identified a star orbiting LB-1, the team next used the world’s largest telescopes — from the United States and Spain — to take a closer look at the system. The results, according to the news release, were “nothing short of fantastic.”

There are two kinds of black holes. Stellar black holes, like LB-1, are made from the evolution and death of stars, which rarely exceed 150 times the mass of the sun when they are born, Bregman said. There are also supermassive black holes, which almost always live in the center of galaxies and range from a million to a few billion times the mass of the sun.

Our own galaxy, the Milky Way, has a supermassive black hole in the center that has a mass of about 4 million suns. How supermassives form is unclear, Bregman said, but it’s possible they are created when stellar black holes merge.

“Black holes are basically the most mysterious objects in the cosmos,” Shep Doeleman, the director of the global Event Horizon Telescope array, has previously told The Washington Post. Even Albert Einstein almost didn’t believe they were real, he said, even though it was his theory of general relativity that helped predict them more than 100 years ago.

Black holes are “the most exotic animals in the cosmological zoo,” Doeleman said; scientists can learn a great deal about the universe by studying what they eat and how they behave.

Bregman said scientists are always trying to learn more about the birth and death of stars, and the discovery of one as large as LB-1 could inform that process.

“Is this object extremely unusual? Or is it more common than we thought?” Bregman said. “If we look at 20 [black holes] and find two of three of these things, that would be truly amazing. It would change ideas of how massive stars evolve and die.”

The study suggests some potential explanations, including the “exciting possibility” that LB-1 might actually consist of two black holes orbiting each other, though Bregman said that would be rare. The study also points to a phenomenon known as fallback supernova, which means that during the supernova stage of a star’s evolution — when it explodes — it only loses a fraction of its mass and the rest falls back into the black hole, increasing its size.

Another option, one Bregman thinks is most likely, is that a very large star did not shed its normal amount of matter as it evolved and before it became a black hole.

“This has big implications for the evolution, the final days, of massive stars,” Bregman said.

Sarah Kaplan contributed to this report.


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« Reply #2166 on: Dec 03, 2019, 04:20 AM »

50 years ago, Apollo 12 made history with US second moon landing

One of NASA's most forgotten missions to the moon, but also one of the funniest

Fermin Koop byFermin Koop
12/3/2019
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While Apollo 11 is the most well-known mission to the moon, the subsequent Apollo missions were also highly valuable missions. Few know of the Apollo 12 mission, but according to Teasel Muir-Harmony, the curator of the Apollo Collection at the Smithsonian National Air and Space Museum in Washington D.C., it was quite the trip.

The mission had a rocky start due to launch-day thunderstorms. While ascending, the space ship was hit twice by lighting which resulted in a host of electrical problems. But thanks to Mission Control, it was able to overcome these problems and restore power to all systems.

And the crew consisted of a unique cast of characters. The mission commander, Pete Conrad, brought a tape deck on board and set his own playlist that included Dusty Springfield and Elvis. He was joined by Alan Bean and Richard Gordon. All three were friends due to their time serving as pilots in the Navy.

While Apollo 11’s primary challenge was to prove that a moon landing was possible, Apollo 12 aimed to improve the process. “The major focus of Apollo 12 was the pinpoint landing,” Harmony said. “Conrad was considered one of the best pilots, if not the best pilot of the Apollo astronauts.”

Conrad successfully landed the ship on the edge of a crater. The landing site was 600 feet away from a robotic probe called Surveyor II, which the team visited during their time on the moon.

The crew’s hijinks are apparent from Conrad’s first words on the moon: “Whoopie! Man, that may have been a small one for Neil, but that’s a long one for me.” This was actually a part of a bet with Harmony, who had asked Conrad if the U.S. government-dictated Armstrong’s first words. This was his response to prove that they are allowed to say anything they want.

Transcripts also show that Conrad sang frequently during his walks on the moon. Unfortunately, there isn’t a lot of footage of the mission itself. Bean ruined the footage in the camera by accidentally pointing it directly at the Sun.

While the crew members of Apollo 12 received the same honors as those of Apollo 11, they didn’t receive as much attention. When they returned, the Vietnam War was in full swing. “It’s hard to feel optimistic and excited and focused on exploration when these horrible atrocities are happening on earth,” said Harmony.


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« Reply #2167 on: Dec 04, 2019, 04:40 AM »

Planets could orbit Supermassive Black Holes

A new theory suggests that planets could form in dense dust and gas clouds surrounding supermassive black holes at the centre of active galaxies.

Rob Lea byRob Lea
ZME
12/4/2019

The idea of stars orbiting the supermassive black holes that researchers believe lurk at the centre of most galaxies has been long established as a matter of fact in science. In ‘active galactic nuclei’ or AGNs, these black holes are surrounded by haloes of gas and dust in a violent churning environment. Such clouds of gas and dust have the potential to birth not only stars but planets as well. Yet, the question of whether planets can also orbit these spacetime events has yet to be established.

Enter Keiichi Wada, a professor at Kagoshima University, and Eiichiro Kokubo, a professor at the National Astronomical Observatory of Japan. These scientists from the distinct fields of active galactic nuclei research and planet formation research respectively have calculated that as a result of gas disc growth, an entirely new class of planets may form around supermassive black holes.

    “With the right conditions, planets could be formed even in harsh environments, such as around a black hole,” Wada points out.

In their research published in the Astrophysical Journal, the duo of theoreticians propose that protoplanetary discs that surround young stars may not be the only potential site for planet formation. The researchers instead focused calculations and mathematical models on the denser dust discs found around supermassive black holes in AGNs, thus arriving at a surprising conclusion.

    “Our calculations show that tens of thousands of planets with 10 times the mass of the Earth could be formed [at a distance of] around 10 light-years from a black hole,” says Eiichiro Kokubo.

    “Around black holes, there might exist planetary systems of astonishing scale.”

One of the hindrances to the formation of planets in such discs of dust has previously been the amount of energy generated in AGNs, Researchers had believed that this energy output would prevent the coagulation of ‘fluffy ice dust’ that can help the growth of dust grains that can lead to planet formation in protoplanetary discs.

But, what Wada and Kokubo discovered was that the huge density of dust discs around supermassive black holes in AGNs —potentially containing as much as a hundred thousand times the mass of the Sun worth of dust, which is a billion times more massive than a typical protoplanetary disc — helps protect the outer layers from bombardment from high-energy radiation such as gamma rays.

This helps form a low-temperature region similar to that found in protoplanetary discs, and thus, in turn, increases the likelihood of fluffy deposits building.

The process would lead to the formation of planets within a period of several hundred million years, according to the pair, and also result in much denser and more populated collections of planets.

Unfortunately, the limits of current methods of identifying exoplanets would make identifying planets around a supermassive black hole challenging to say the least.

    “ Doppler spectroscopy, transit photometry, gravitational micro-lensing, or direct imaging are hopeless,” warn the duo in their paper. They go on to suggest that a method called photometry with an x-ray interferometer located in space could be a possible solution — if a way of distinguishing the effect caused by such planets from the natural variability of the AGN can be developed.

For now, researchers will have to look to mathematical models alone to theorise about the potential for planets in orbit around black holes.

Original research: https://arxiv.org/pdf/1909.06748.pdf


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« Reply #2168 on: Dec 05, 2019, 04:25 AM »


Sun yields its secrets to Parker Solar Probe

on December 5, 2019
By Agence France-Presse

NASA’s Parker Solar Probe, having survived its closest encounter so far with the Sun, has sent back a “spectacular trove” of data on its corona, the super-hot outer edge of its atmosphere, scientists said Wednesday.

The car-sized probe, launched in August last year, will come within some four million miles (six million kilometres) of the sun’s surface during a series of fly-bys at other distances and trajectories over seven years.

It is hoped it will allow a better understanding of the solar wind and electromagnetic storms which can cause chaos on Earth by knocking out the power grid.
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One puzzle concerns the corona itself which at one million degrees is many times hotter than the sun’s surface at 6,000C, when it would normally be expected to cool the further from the heat source.

“So the corona finds a way to heat up. We are looking at the physical processes which allow that to happen,” said Alexis Rouillard at France’s National Centre for Scientific Research (CNRS) and co-author of one of four reports on the probe’s initial findings published in the journal Nature.

“Even with just these first orbits, we’ve been shocked by how different the corona is when observed up close,” said Justin Kasper, a professor of climate and space sciences and engineering at the University of Michigan.

A summary by the University of Michigan noted that it had been thought that oscillations in the Sun’s magnetic field might have caused the corona to heat up and were expecting to get data to confirm that.

Instead, they reported much more powerful, “rogue” magnetic waves strong enough to switch the direction of the magnetic field completely that may be the energy source for the corona.

– ‘Missing something fundamental’ –

Scientists were also surprised by what they found about the acceleration of the solar wind, the outward stream of protons, electrons and other particles emanating from the Sun.

It was known that closer in, the Sun’s magnetic field pulls this wind in the same direction as its rotation, so the team expected this effect would weaken further out.

“To our great surprise, as we neared the Sun, we’ve already detected large rotational flows — 10 to 20 times greater than what standard models of the Sun predict,” Kasper said.

“So we are missing something fundamental about the Sun and how the solar wind escapes.

“This has huge implications. Space weather forecasting will need to account for these flows if we are going to be able to predict whether a coronal mass ejection will strike Earth, or astronauts heading to the Moon or Mars,” he added.

Stuart Bale, professor of physics at the University of California Berkeley, recalled that a “major space weather event” in 1859 blew out telegraph networks on Earth and one in 1972 set off US naval mines in North Vietnam.

With society now even more dependent on sophisticated technology, “big disturbances from the sun are potentially a very serious thing,” Bale said.

“If we could predict space weather, we could shut down or isolate parts of the power grid, or shut down satellite systems that might be vulnerable.”


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« Reply #2169 on: Dec 06, 2019, 04:45 AM »

An alien comet from another star is soaring through our solar system

Sarah Kaplan
WA Post
12/6/2019 at 8:00 AM EST

SEWANEE, Tenn. — Something strange is sailing toward us. Something small and cold and extraordinarily fast. No one knows where it came from or where it is going. But it’s not from around here.

This is an interstellar comet — an ancient ball of ice and gas and dust, formed on the frozen outskirts of a distant star, which some lucky quirk of gravity has tossed into our path.

To astronomers, the comet is a care package from the cosmos — a piece of a place they will never be able to visit, a key to all the worlds they cannot directly observe.

It is only the second interstellar interloper scientists have seen in our solar system. And it’s the first one they’ve been able to get a good look at. By tracking the comet’s movement, measuring its composition and monitoring its behavior, researchers are seeking clues about the place it came from and the space it crossed to get here. They have already found a carbon-based molecule and possibly water — two familiar chemicals in such an alien object.

As the sun sinks behind the Tennessee mountains, and stars wink into view, astronomer Doug Durig climbs onto the roof of his observatory, powers up his three telescopes and angles them skyward.

Every night, the comet grows bigger and brighter in the sky, expelling streams of gas and dust that may offer up clues to its history. On Dec. 8, it will make its nearest approach to Earth, offering researchers an up-close glimpse before it zooms back into the freezing, featureless void.

Far below in the darkness, Durig will be waiting.
An unmarked package from the universe

Each star in the night sky represents a possible solar system. Every light in the universe is, more likely than not, some alien planet’s sun.

This is the chief lesson of two decades of studying exoplanets. Scientists have identified thousands of worlds beyond our solar system: gas giants and tiny rocky spheres, worlds lit by dim red suns and ones that orbit the spinning remains of collapsed stars. There are even planets circling medium-size yellow suns like ours — though nothing found so far can match the breathable atmosphere and deep, blue oceans of Earth.

Yet even when viewed through the most powerful telescopes, exoplanets are not discernible as anything more than specks of light. And no human alive has a hope of traveling to another star — merely approaching the nearest one would take 40,000 years.

Scientists’ best hope for closely examining another solar system was to wait for a piece of one to come to us.

It was Aug. 30, in the quiet moments before dawn, when a self-taught astronomer in a Crimean mountain village spotted a faint smudge low on the horizon, barely distinguishable against the glittering background of stars.

Gennady Borisov submitted his observations to the Minor Planet Center, the astronomers’ clearinghouse for information about small bodies in the solar system, so other scientists could take a look.

One night later, halfway across the planet, the strange report caught Durig’s eye.

“I was the second person to observe it,” Durig said. “That confirmed the comet was real.”

Within a couple of weeks, scientists had collected enough observations to calculate the comet’s orbit. But they did not find the oval path that comets typically make around the sun. Instead, the orbit was hyperbolic — it did not close in on itself. The object was also traveling at the blistering speed of 93,000 miles per hour, far faster than any comets, asteroids or planets orbiting our sun.

“Wow,” said Davide Farnocchia, a navigation engineer at NASA’s Jet Propulsion Laboratory, who was among the first people to determine that the comet came from another star. “I was not expecting to see anything like that.”

There has been only one other interstellar object spotted in our solar system: a cigar-shaped rock named ‘Oumuamua, a Hawaiian word that translates to “messenger from afar.”

But ‘Oumuamua was already on its way out of the system when it was discovered in October 2017, and it was so faint that scientists were never able to view it as more than a single pixel of light. They were not quite sure what they had seen — was it a metallic, rocky asteroid or an icy, dusty comet? And they were unsure whether the detection was just a lucky fluke, never to be repeated, or a harbinger of things to come.

So researchers were thrilled when, less than two years later, another interstellar traveler arrived.

The new comet, which has been named 2I/Borisov (indicating its discoverer and its status as the second known interstellar object), is expected to be within reach of telescopes until fall 2020. At its closest approach, next month, it will be twice as far from Earth as Earth is from the sun.

Though it entered the solar system from the direction of the constellation Cassiopeia, scientists do not know yet where 2I/Borisov came from, or how long it has flown through the desolation of interstellar space. Given its current speed, it has certainly been traveling for millions, if not billions, of years.

As the object gets closer to the sun’s warmth, ices on its surface turn into gas. This creates the characteristic halo-like “coma,” which scientists can scrutinize to determine what the comet is made of. Already, 2I/Borisov has been observed more than 2,000 times.

“That’s going to be fun, in terms of looking at this object . . . as it comes in from the deep freeze for the very first time,” said Michele Bannister, an astronomer at Queen’s University Belfast. “Let’s open it up and see what we have with this particular present from another star.”
'Little wanderers roving across the galaxy'

Exoplanet discoveries revealed we live in a crowded cosmos. But they also awakened Earthlings to how lonely we are. Most planetary systems discovered in recent decades are wildly unfamiliar, and the most common type of exoplanet — a body larger than Earth but smaller than Neptune — doesn’t exist near our home.

When astronomers had only our own solar system to go by, “it used to seem like planet formation was solved,” said Malena Rice, an astrophysicist at Yale University. “And then all of a sudden there are all these strange systems that don’t fit our picture.”

Interstellar comets are uniquely useful for confronting this conundrum. They are born of the same swirling disk of gas and dust that produces planets around an infant star. But then they get stranded at the icy edges of solar systems, where they can preserve the early ingredients of planet formation.

Comets in our own solar system have been found to contain some of the basic ingredients for life: water, carbon, even complex organic compounds. Now 2I/Borisov could tell us whether life’s essential molecules were among the building blocks of a world beyond our own.

This fall, Bannister’s colleague Alan Fitzsimmons produced the first-ever detection of a chemical compound emitted by an interstellar comet. Separating light from 2I/Borisov into its component parts, his team found a signature of cyanogen, a molecule made of a carbon atom and a nitrogen atom bonded together. The gas is common in comets around this sun.

“When I saw that, I shouted in my office . . . something not repeatable in a respectable newspaper,” Fitzsimmons recalled.

A few weeks later, astronomer Adam McKay detected oxygen streaming off the comet, an indicator that sunlight is striking water on the surface and breaking up the molecule. If confirmed, this would be the first-ever detection of alien water in our solar system. It is also another sign that 2I/Borisov is much like the comets we know.

“Even in these other systems where their architectures are very different, maybe the underlying physics and chemistry is still pretty similar,” said McKay, a research scientist at NASA’s Goddard Space Flight Center.

Models of our solar system suggest that about 90 percent of the leftover material from planet formation was ejected into interstellar space. The space beyond Neptune still harbors millions of icy bodies, which over millennia can be knocked out of orbit and slung away from the sun.

If any of these scattered fragments happen to be pulled into another system and start to glow in the heat of its star, they will appear as interstellar comets to whoever might be watching.

“There’s a universality to that, which is amazing,” Bannister said. “Our planetary system is woven together with another planetary system by these little wanderers roving across the galaxy.”
The long night

With just an hour to go until daybreak, 2I/Borisov is due to appear above the horizon and make its way across the eastern sky. Durig’s long night is almost over.

Sewanee: The University of the South, the 1,600-student liberal arts college where Durig works, does not have the massive instruments needed to resolve faint night-sky objects. Instead, he must take hundreds of images of the same spot, then use a computer program to layer them so dim lights become clear.

The astronomer checks the focus of his 12-inch Schmidt-Cassegrain telescope and sets it to work, snapping pictures of the place where the interstellar comet is expected to be. He rubs a hand across his eyes, itchy from hours spent beneath the dim red lights he uses to protect his night vision.

It is tiring and often tedious work. Unlike discoverers, follow-up observers do not get to put their names on anything. And unlike researchers working at the world’s largest observatories, someone such as Durig faces real hurdles in achieving the findings that get published in prestigious journals.

Still, extraordinary discoveries must be confirmed and refined, again and again, by ordinary people. News may be made by breakthroughs, but knowledge is cemented in the follow-ups.

Here in Sewanee’s cramped observatory, cluttered with stacks of observation records and piles of broken equipment he hopes to one day refashion into something usable, “we’re doing essential science,” Durig says. “We’re filling in all the gaps.”

Once his telescope has captured an hour’s worth of snapshots, Durig compiles them into stacks of 100. In the images that emerge, colors are inverted, so stars appear as black smears on a white background. In the lower left is a dark dot encircled in a halo of fuzz.

Durig clicks forward to the next stack, and the dot moves by a centimeter. Another click, and it moves again.

That’s how he knows he is looking at the comet, something swift and surrounded by dust, something that does not behave like anything else in the sky.

Durig sends his images and a record of the comet’s location to the Minor Planet Center — another drop of data in the bucket of scientific knowledge.

Consistent observations like this, conducted by the same people using the same instruments every night, will be even more important once the comet becomes visible in the Southern Hemisphere, where many of the world’s biggest telescopes are positioned. They need to be pointed with extreme precision, so astronomers must have a firm handle on the comet’s trajectory and things that might subtly alter it, such as outbursts of gas.

An accurate orbit is also key to astronomers’ most ambitious plan for the comet.

“If we can get the best possible trajectory, so we can trace it back with the exact direction it’s coming in . . . maybe we can find out what the origin system is,” said Farnocchia, the Jet Propulsion Laboratory engineer.

Identifying the comet’s parent star would be a tremendous feat, the astronomical equivalent of tracing a message in a bottle back to the person who sent it millions of years ago from billions of miles away. It may not turn out to be possible, most scientists acknowledge.

But maybe that’s okay, they say. Because the comet will have already revealed so much else. It will have told us something about the birth of solar systems. It will have connected our home to the workings of the wider galaxy. And now that we have seen it, it is easier to believe that more are out there to be found.

Here on Earth, together in the darkness, Durig and his fellow astronomers will be waiting.


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« Reply #2170 on: Dec 07, 2019, 04:55 AM »

Hunting for exoplanets: past and future

The last decade of space exploration has exceeded even our wildest expectations. And this is only the beginning.

Tibi Puiu
December 7, 2019
ZME

In 2018, NASA’s Kepler Space Telescope mission came to a predictable end after it ran out of fuel some 94 million miles from Earth. During its nine-year planet-hunting mission, Kepler discovered nearly 3,000 exoplanet candidates and more than 2,600 confirmed exoplanets in our galaxy, cementing the notion that our solar system isn’t all that special. So far, 55 exoplanets that are potentially habitable — meaning they orbit their stars at just the right distance that may allow water to flow on the surface — have been found, of which 20 are Terran or Earth-sized.

There are at least as many planets as there are stars in the galaxy

After studying thousands of exoplanets astronomers are now confident that:

    Relatively small planets are common;
    There are likely more planets than stars in the galaxy;
    Planetary systems are flat like the solar system;
    Planets and planetary systems are extremely diverse;
    No exoplanets similar to Earth in size, distance, and type of star they orbit have been found.

Artist concept of Kepler in space. Image credit: NASA/JPL

    “I think that exoplanets tell us about our place in the universe. That’s probably the main reason the discovery of the first exoplanets were awarded the Nobel Prize in Physics this year. We are seeing just how diverse planets are. Planets are more common than they were thought to be before the first exoplanets were found. The number of planets in our galaxy is at least as large as the number of stars. But while planets and planetary systems are so diverse, planets like Earth may be very, very rare,” Dr. Jack Lissauer, a scientist at the NASA Ames Research Center and co-investigator of the Kepler mission, told ZME Science at the World Science Forum in Budapest. The World Science Forum is a biannual international conference on global science policy, which is affiliated with UNESCO and ICSU.

An exoplanet is any planet orbiting a star other than the Sun. Just 24 years ago, we only knew of planets in our solar system — but not for lack of trying. Detecting exoplanets is very challenging because they’re much smaller and fainter than stars. Since exoplanets are not self-luminous, scientists had to think outside the box.

The most successful exoplanet detection method is transit photometry, which looks for periodic, repetitive dips in the visible light of stars caused by planets passing, or transiting, in front of them. Essentially, a transit is just a partial eclipse.

    “It was getting all the precision to detect the small variations in the light of the stars for planetary transits. To be able to detect planets — actually the smallest one that we’ve found was about the size of Earth’s moon, it’s the smallest planet known,” Lissauer said.

This has led to some incredibly unexpected discoveries that exceeded even our wildest expectations. Planets such as Kepler-22b, which is a water world between the size of Earth and Neptune located more than 600 light-years away or Kepler-16b, which is part of a ‘Tatooine-like’ system 200 light-years away — it is home to the largest planet ever discovered orbiting two stars. Then there’s the exciting Kepler-11 system, home to no fewer than six planets and the fullest, most compact planetary system yet discovered beyond our own.

    “A year before that, or even eight months before that, no multi-planetary transiting system had been discovered. By the time of Kepler-11 discovery, there were two others. One had three planets, one had two planets, Kepler-11 had six. And we were able to derive the masses of the inner five by the perturbations they gave on one another so the transits were not periodic. It contains five of the lowest mass exoplanets at the time for which we had measurements of both their size and their mass, so we could have good estimates of what they’re made of, by getting their density,” Lissauer told ZME Science.

The car-sized telescope was launched primarily to detect small planets. For this purpose, it was designed to find out how many planets are out there not by observing the entire galaxy but by taking a sample in and near the habitable zone — the region at the right distance from the star so that the surface has liquid water.

Beyond Kepler

Although it has been decommissioned, Kepler’s legacy lives on. Scientists are still sifting through thousands of candidate exoplanets, a task which will keep them busy for many years to come. Kepler has also shaped future missions such as the Transiting Exoplanet Survey Satellite, or TESS.

Launched in April 2018, TESS is NASA’s latest planet hunter. Its mission is to survey planets orbiting 200,000 of some of the brightest stars close to Earth. Later, planets identified by TESS can be inspected for a closer look by the upcoming James Webb Telescope.

    “I’m a co-investigator on TESS as well as Kepler and I think of Kepler as having done great science by detecting these very small planets — planets not hugely different from Earth in their properties, in some cases,” Lissauer said.

    “TESS won’t detect planets as small and as long-period orbits as Kepler — it has much smaller cameras — but it detects planets around brighter stars. So, the purpose of TESS is really finding planets around very bright stars so there’s enough light from these stars that we can detect light passing through their thin atmosphere where they transit their stars. So, TESS is enabling us — with other instruments, especially the James Webb Telescope, which will be launched in two years, and some of the very large and extremely large telescopes on the ground — to study the composition of the atmospheres of mid-sized exoplanets. Not Earth analogs — that’s too difficult — but not these hot Jupiters. So, planets a big step closer to our own,” he added, explaining TESS’ major role in future planet-hunting efforts.

Besides TESS, there are exciting exoplanet-hunting missions. Europe’s CHaracterising ExOPlanets Satellite (CHEOPS) mission is destined to launch in December. Its mission is to that of a follow-up: it will be tasked with studying stars known to harbor planets, rather than surveying the sky in search of new ones.

By performing observations of multiple planetary transits, CHEOPS will be able to provide more precise measurements of a planet’s size, which can be combined with existing mass determinations to render accurate densities. Knowing these parameters, it is possible to determine the exoplanet’s composition and discriminate between Earth-like planets where life may blossom and other types of Earth-mass planets that challenge our current notions of habitability.

In 2026, ESA will launch PLATO, which is short for the PLAnetary Transits and Oscillations of stars) mission. PLATO is designed to find and determine the properties of Earth-like planets that orbit the habitable zone around stars similar to the Sun. For the first time, PLATO will allow scientists to calculate accurately the properties of a large number of stars with planets, including their ages.

Meanwhile, ESA’s ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) mission is destined to study and characterize exoplanets, rather than discover them. ARIEL is scheduled to launch in 2028. The mission is designed to perform high-accuracy transit, eclipse, and phase-curve multiband observations of exoplanets. Scientists are confident that ARIEL will be able to provide a complex picture of the chemical nature of its targeted exoplanets, but also their host stars. This will allow researchers to investigate the nature of these exoplanets, how they formed, and how they evolved.

Kepler opened the gate for mankind’s exploration of the cosmos, and its successors are bound to offer even more surprises. There are billions — perhaps trillions — of stars in the Milky Way galaxy alone and, on average, each of those stars has at least one planet orbiting them. However, there really is no place like home.

    “We only have Earth. It’s possible that there are other planets like Earth out there but even if they are very similar, they are very far away. We can’t do a migration. We can’t solve our problem as the Irish did in the late 1800s to solve the potato famine. We would be like Easter Island. If we don’t take care of this planet, we are toast! All the mass extinctions in the last 5 million years are coincident with the rise of CO2 in the atmosphere of our planet. We must stop this crazy behavior. We can’t just say something has to be done. We have to do things ourselves. We have to cut our carbon footprint,” Lissauer told the audience during an event at the 2019 World Science Forum, held between 20-24 November.


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« Reply #2171 on: Dec 09, 2019, 04:46 AM »


NASA is losing its patience with its misbehaving Mars mole

Mike Wehner
BGR
12/9/2019

NASA’s InSight lander is really starting to give scientists a headache. Most of the lander’s high-tech sensors and systems are working just fine, and it’s already returned some interesting data on rumbles that researchers suspect are “Marsquakes,” but one instrument, in particular, is failing to meet expectations.

The self-hammering “mole” probe which was supposed to dig deep within the planet to return temperature data has been unable to dig as deep as it’s designed to. In fact, it hasn’t even gotten close to reaching its maximum depth of 16 feet, only managing to push itself about a foot into the surface before stalling out.

InSight’s mission team initially believed it was simply failing to get a grip on the looser-than-expected Martian soil. To solve that problem, the lander removed a protective shroud from around the mole and used its robotic arm to pin the mole against the side of its hole. This gave it a bit more traction and, for a moment, it appeared to work.

Unfortunately, after digging itself about an inch deeper, the mole was pushed back out of the hole. As NPR reports, the InSight team thinks it knows why that happened, but it didn’t make it any less disappointing. Troy Hudson, an instrument system engineer on InSight, explained that the hole likely filled up with loose material after the lander’s robotic arm backed off from its pinning technique.

“When it does that, loose soil in front of the mole can infiltrate in front of the tip, filling up the space that occurs whenever it bounces,” Hudson explained. “Then it’s just ‘bounce, bounce, bounce, bounce,’ and more material fills in and it ends up backing out of the ground.”

Hudson, who said he was “very distraught” when he saw that the progress the mole made had been undone, says the team is now using the lander’s arm to physically push the mole into the hole. However, that will only work for so long, and once the mole’s body is completely beneath the surface they’re going to have to invent a new way to ensure it continues to dig.


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« Reply #2172 on: Dec 09, 2019, 05:49 AM »

Such a shame that the most important functionality on the probe is having issues. Hopefully they can do something remotely.
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« Reply #2173 on: Dec 10, 2019, 04:55 AM »


That AI robot that had an emotional meltdown in space got an upgrade

Mike Wehner
December 10, 2019
BGR

SpaceX was finally able to launch its Dragon cargo spacecraft to the International Space Station this week after the initial launch was scrubbed due to poor weather conditions. The spacecraft is carrying a whole bunch of neat stuff to the ISS, including an upgraded version of an AI-powered floating robot that lost its cool when interacting with its astronaut handler.

Roughly a year ago, the CIMON robot was being tested for its ability to act as a robotic assistant for the scientists aboard the space station. It’s designed to provide information about crucial tasks, provide reminders, and offer helpful tips. Unfortunately, the first iteration of the bot that was tested in space had some emotional demons.

ESA published a video showcasing the robot doing its thing on the space station in December of last year. Things seemed to be going well, but the robot spontaneously started acting, well, bizarre. It seemed to get its “feelings” hurt, then interrogated its handler, Alexander Gerst. It accused Gerst of being “mean” and then demanded to know whether Gerst liked it or not. It was incredibly odd.

As Reuters reports, this upgraded version is also equipped with “emotion-sensing” features. Whether it’ll be as moody as the first CIMON bot remains to be seen.

“The overall goal is to really create a true companion,” lead architect of CIMON 2 told Reuters. “The relationship between an astronaut and CIMON is really important. It’s trying to understand if the astronaut is sad, is he angry, joyful and so on.”

AI has the potential to be a huge ally for astronauts on the space station as well as space travelers participating in future missions to other worlds. Eventually, groups like ESA and NASA believe that AI will be capable of running the show, so to speak, and maintaining various spacecraft systems while allowing human scientists more time to focus on science.

Watch: https://www.youtube.com/watch?v=3_2Jy1Ur0js&feature=emb_title

**************

ESA’s adorable space station AI had an emotional meltdown in his debut

Mike Wehner
BGR
December 3rd, 2018

It’s been many months since the European Space Agency announced that it was building an AI for testing aboard the International Space Station. Named “CIMON” (short for Crew Interactive Mobile Companion), the digital helper is finally up and running aboard the ISS, and space station crew are getting a chance to test it out.

No, we’re not in for a HAL-9000 type of scenario (at least not yet), but CIMON definitely still has some quirks to be worked out. In a hilarious debut, the smiling artificial face gives astronauts a good chuckle as it starts to act a bit wonky, and it was all captured on video for us to enjoy.

The tiny robot, which has fans that allow it to push itself around a room as well as maintain position in the zero-gravity environment of the ISS, shows some impressive capabilities to start. It responds to voice commands and makes suggestions just as it should, but then things start to get a little, well, weird.

After using its music feature, the tiny bot refuses to stop talking about music. It also begins to drift towards the floor of the spacecraft and handler Alexander Gerst has to reposition it. Then, seemingly out of nowhere, CIMON begins to get emotional, asserting that Gerst is “mean” and asking “Don’t you like it here with me?”

Gerst can do nothing but laugh at the abrupt change in tone. CIMON then suggests that Gerst must be hungry and asks if Gerst would like to be reminded when it’s time for lunch.

It’s honestly one of the funniest videos ever to come from the ISS, not to mention slightly creepy. The robot clearly has some emotional baggage that it brought with it for its stay aboard the space station, but I’m sure ESA will hammer out the kinks in time.


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« Reply #2174 on: Dec 11, 2019, 04:20 AM »


Saturn’s ice moon Enceladus has icy ‘tiger stripes,’ and scientists just figured out why

Mike Wehner
BGR
12/11/2019

Of all the places in our solar system where life might be hiding out, Saturn’s frosty moon Enceladus might be the most tantalizing. The Moon is a vast ocean covered by an icy shell, and NASA’s Cassini mission offered intriguing glimpses of huge liquid water geysers erupting into space through cracks in the thick ice.

Enceladus is instantly recognizable thanks to its bold blue “tiger stripes,” which run parallel to each other across the moon’s south pole. Researchers have long wondered why this pattern emerged, and after carefully considering the possibilities and looking at all the available data, they think they’ve come up with the answer.

In a new study published in Nature Astronomy, a team of researchers at Carnegie Science offers their best guesses as to how the stripes formed, and why they persist over time.

“First seen by the Cassini mission to Saturn, these stripes are like nothing else known in our Solar System,” Doug Hemingway, who led the research, explains. “They are parallel and evenly spaced, about 130 kilometers long and 35 kilometers apart. What makes them especially interesting is that they are continually erupting with water ice, even as we speak. No other icy planets or moons have anything quite like them.”

Based on what we know about Enceladus, it’s believed that the ice near the poles of the moon is thinner than elsewhere on the frosty orb. As temperatures on the moon change gradually over time, lower temperatures lead to the freezing of the ocean below the surface. Water expands when it freezes, placing greater stress on the outer layer of ice, and eventually that stress causes the ice to fracture.

As for why the cracks appear on the south pole of the moon, the researchers say that it may just be random chance. The relief of the pressure from below could have caused cracks to form at either of the poles, and the fact that the cracks appear at the south pole is “a bit of a coin toss.”


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