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Nov 18, 2019, 03:46 PM
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Author Topic: NEWS ON SPACE AND OUR PLANETARY SYSTEM  (Read 641130 times)
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Darja
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« Reply #2115 on: Oct 03, 2019, 03:36 AM »


Astronomers spot a trio of black holes on a devastating collision course

Mike Wehner
BGR
10/3/2019

Black holes are one of the most interesting features of our universe. So incredibly dense that their gravitational pull can swallow up light itself, they are enormously powerful on their own, but when three of them get together? Well, that’s a recipe for some serious fireworks.

As NASA’s Jet Propulsion Laboratory explains in a new post, astronomers using powerful imaging hardware, including three of NASA’s own telescopes, have spotted a trio of black holes in the midst of a cosmic dance. The holes were spotted in a distant galactic collision that could offer hints at the fate that awaits our own Milky Way.

Black holes are thought to exist at the center of most galaxies, and supermassive black holes are the largest and most powerful variety. It’s believed that a supermassive black hole rests at the heart of our own galaxy, but the system known as SDSS J084905.51+111447.2 has not one, not two, but three such black holes, making it an incredible oddity.

To make their discovery, a team of astronomers relied on several different imaging techniques including infrared, X-ray, and optical sensors. Combining all of these observations allowed the scientists to spot the black hole group, and the team describes its findings in a new paper published in The Astrophysical Journal.

As it appears right now, the system is thought to be the result of an ongoing galaxy merger, with the trio of black holes all carrying their own galaxies into the fray. Our home galaxy, the Milky Way, is believed to be on a similar collision course with the neighboring Andromeda galaxy, though it will take several billion years before that occurs.

“We were only looking for pairs of black holes at the time, and yet, through our selection technique, we stumbled upon this amazing system,” Ryan Pfeifle, first author of the study, said in a statement. “This is the strongest evidence yet found for such a triple system of actively feeding supermassive black holes.”


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« Reply #2116 on: Oct 04, 2019, 03:42 AM »


What moons in other solar systems reveal about planets like Neptune and Jupiter

on October 4, 2019
By The Conversation

What is the difference between a planet-satellite system as we have with the Earth and Moon, versus a binary planet – two planets orbiting each other in a cosmic do-si-do?

I am an astronomer interested in planets orbiting nearby stars, and gas giants – Jupiter, Saturn, Uranus and Neptune in our solar system – are the largest and easiest planets to detect. The crushing pressure within their gassy atmosphere means they are unlikely to be hospitable to life. But the rocky moons orbiting such planets could have conditions that are more welcoming. Last year, astronomers discovered a planet-sized exomoon orbiting another gas giant planet outside our solar system.

In a new paper, I argue that this exomoon is really what is called a captured planet.

Is the first detected ‘exomoon’ really a moon?

True Earth analogues, that orbit Sun-like stars, are very hard to detect, even with the large Keck telescopes. The task is easier if the host star is less massive. But then the planet has to be closer to the star to be warm enough, and the star’s gravitational tides may trap the planet in a state with a permanent hot side and a permanent cold side. This makes such planets less attractive as a potential location that could harbor life. When gas giants orbiting Sun-like stars have rocky moons, these may be more likely places to find life.

In 2018, two astronomers from Columbia University reported the first tentative observation of an exomoon – a satellite orbiting a planet that itself orbits another star. One curious feature was that this exomoon Kepler-1625b-i was much more massive than any moon found in our solar system. It has a mass similar to Neptune and orbits a planet similar in size to Jupiter.

Astronomers expect moons of planets like Jupiter and Saturn to have masses only a few percent of Earth. But this new exomoon was almost a thousand times larger than the corresponding bodies of our solar system – moons like Ganymede and Titan which orbit Jupiter and Saturn, respectively. It is very difficult to explain the formation of such a large satellite using current models of moon formation.

In a new model I developed, I discuss how such a massive exomoon forms through a different process, wherein it is really a captured planet.

All planets, large and small, start by gathering together asteroid-sized bodies to make a rocky core. At this early stage in the evolution of a planetary system, the rocky cores are still surrounded by a gaseous disk left over from the formation of the parent star. If a core can grow fast enough to reach a mass equivalent to 10 Earths, then it will have the gravitational strength to pull gas in from the surrounding space and grow to the massive size of Jupiter and Saturn. However, this gaseous accumulation is short-lived, as the star is draining away most of the gas in the disk, the dust and gas surrounding a newly formed star.

If there are two cores growing in close proximity, then they compete to capture rock and gas. If one core gets slightly larger, it gains an advantage and can capture the bulk of the gas in the neighborhood for itself. This leaves the second body without any further gas to capture. The increased gravitational pull of its neighbor drags the smaller body into the role of a satellite, albeit a very large one. The former planet is left as a super-sized moon, orbiting the planet that beat it out in the race to capture gas.

A remnant core as a look back into history

Viewed in this context, the captured planet is unlikely to be habitable. Growing planetary cores have gaseous envelopes, which make them more like Uranus and Neptune – a mix of rocks, ice and gas that would have become a Jupiter if it had not been so rudely cut off by its larger neighbor.

However, there are other implications that are almost as interesting. Studying the cores of giant planets is very difficult, because they are buried under several hundred Earth masses of hydrogen and helium. Currently, the JUNO mission is attempting to do this for Jupiter. However, studying the properties of this exomoon may enable astronomers to see the naked core of a giant gaseous planet when it is stripped of its gaseous envelope. This can provide a snapshot of what Jupiter may have looked like before it grew to its current enormous size.

This exomoon system Kepler-1625b-i is right at the edge of what is detectable with current technology. There may be many more objects like this that could be uncovered with future improvements in telescope capabilities. As astronomers’ census of exoplanets continues to grow, systems like the exomoon and its host highlight an issue that will become more important as we go forward. This exomoon reveals that the properties of a planet are not solely a consequence of its mass and position, but can depend on its history and the environment in which it formed. The Conversation

Exomoons may reveal secrets about how gas giants like Jupiter formed and what is in their core.
JPL/NASA

Bradley Hansen, Professor of Physics and Astronomy, University of California, Los Angeles


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« Reply #2117 on: Oct 05, 2019, 04:38 AM »


NASA’s Juno orbiter has to jump over Jupiter’s shadow, or die trying

Mike Wehner
BGR
10/5/2019

NASA’s Juno orbiter has been doing some really great work while in orbit around gas giant Jupiter. The spacecraft has taught scientists a great deal about the planet, as well as the processes that power its massive storms and swirling clouds. The mission has been an incredible success already, but NASA wants to keep it going as long as possible and doing so means avoiding Jupiter’s shadow.

Juno is solar-powered. It has thrusters that allow it to tweak its trajectory, but the juice that keeps its instruments up and running (and prevents them from freezing) comes from the Sun. As you might expect, avoiding the shadow of the largest planet in our solar system is tricky when that’s the planet you’re orbiting.

As a new update posted by the Juno team explains, the spacecraft was recently tasked with an exceptionally long thruster burn in order to adjust its path and allow it to “jump” over Jupiter’s shadow. The burn lasted over 10 hours, which is five times longer than any other burn in Juno’s mission thus far, but the spacecraft pulled it off.

The risks were incredibly great if Juno couldn’t fire its thrusters long enough to push it into a new path around the planet. As NASA explains, the orbiter’s previous trajectory would have sent it on a frigid 12-hour journey across the shadow Jupiter casts from the Sun, and that would likely have been a death sentence. The chances that it would wake back up after enduring that deep freeze are incredibly slim.

“With the success of this burn, we are on track to jump the shadow on Nov. 3,” Scott Bolton, Juno principal investigator, said in a statement. “Jumping over the shadow was an amazingly creative solution to what seemed like a fatal geometry. Eclipses are generally not friends of solar-powered spacecraft. Now instead of worrying about freezing to death, I am looking forward to the next science discovery that Jupiter has in store for Juno.”

NASA expects Juno’s mission to last through mid-2021, at which point it will perform a controlled deorbit that will destroy the spacecraft. In the meantime, we look forward to all the exciting things it has yet to show us.


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« Reply #2118 on: Oct 07, 2019, 04:02 AM »


Black holes might not be black holes at all

Mike Wehner
10/7/2019

Of all the features of our universe, black holes might be the most interesting, as well as the most frightening. These ultra-dense spots in space suck in everything around them, and once a black hole has you in its grasp, there’s quite literally no escaping it.

For a long time, scientists have believed that black holes are impossibly tiny dots of incredible mass, called a singularity. This explanation meshes pretty well with our understanding of physics and how objects move an interact in space. But what if black holes are something completely different? A pair of researcher papers published in The Astrophysical Journal argues that point, and if you can wrap your head around it, it’s one heck of an idea.

In some of the most widely-accepted mathematical equations used to explain the expansion of our universe, black holes aren’t factored in. The researchers in this study attempted to make the math of black holes fit within this framework and discovered that the only way it works is if black holes are in fact not singularities at all.

Instead, the scientists suggest that black holes are actually object made of dark energy. They call these hypothetical objects GEODEs (Generic Objects of Dark Energy) and argue that looking at them in this way could answer a number of questions. Specifically, the theory could reveal where dark energy, which scientists believe is contributing to the expansion of the universe, is collected.

GEODEs, the scientists say, would actually get heavier over time as the universe expands, even without slurping up more matter from their surroundings. In some past observations of black holes and black hole mergers, predictions regarding mass have not worked out as expected. If black holes were in fact GEODEs, the math is far easier to work out.

As interesting as this theory is, it’s far from a sure thing. There’s still an incredible amount of observational work that will need to be done before we have a solid idea of what’s going on in those black pits of nothingness in space.


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« Reply #2119 on: Oct 08, 2019, 03:50 AM »


Fireballs spotted above Chile defy explanation

Mike Wehner
BGR
10/8/2019

When we Earthlings spot something tearing through the sky in a blaze of glory, there’s almost always a totally reasonable explanation. More often than not, tiny chunks of space rock are the culprit, and when they slam into Earth’s atmosphere the friction is enough to set them ablaze. A recent fireball sighting in Chile is apparently not as easy to explain, and scientists still aren’t sure exactly what they saw.

As LiveScience reports, multiple fireballs lit up the skies in Chile just last week, and at the time it was assumed they were meteorites. A handful of the fireballs survived long enough to hit the ground, and when they did, they sparked small blazes that were quickly extinguished by firefighters.

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Normally, this would be the part where researchers step in to say that they found remnants of space rocks, easily explaining away the objects as nothing more than a natural phenomenon. That hasn’t happened, and scientists who examined the sites where the fiery objects came down haven’t found anything to suggest the fireballs were actually meteorites.

    Se reporta caída de meteorito en mocopulli chiloe pic.twitter.com/7w3KGEgnln

    — marcelo macaya (@mmacaya) September 25, 2019

The only other obvious possibility is that the objects were actually manmade debris that fell to Earth from orbit. There’s a whole lot of human space junk tumbling around Earth, and that trash frequently finds itself falling back down in a streak of flame.

Still, the fact that no obvious debris was spotted near any of the fiery crash sites is odd. If it was indeed manmade debris, and it survived long enough to make it to the ground and set foliage on fire, you’d expect that there would be something left over.

In any case, the investigation is still ongoing. Perhaps the debris left over, whether manmade or natural, was simply too charred to identify, or maybe it was aliens. Just kidding! It was definitely not aliens… probably.


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« Reply #2120 on: Oct 09, 2019, 03:25 AM »

NASA’s Curiosity rover paints ancient Mars as a water-rich paradise

Mike Wehner
BGR
10/9/2019

NASA’s Curiosity rover is currently cruising around an area of Mars known as the Gale Crater. It’s a massive impact site that has existed for billions of years, and the version of it we see today hints at a much wetter time on Mars, when water flowed freely into the crater to form rivers and lakes.

Researchers are using observations from Curiosity to paint a picture of Mars as a watery world, and there’s no shortage of evidence to support it. As NASA’s Jet Propulsion Laboratory highlights, a new paper published in Nature Geoscience uses the layers of sediment that make up the towering structure within the crater, known as Mount Sharp, to estimate when the climate of the Red Planet changed.

The Gale Crater is a perfect place for scientists to try to look back in time. On a much wetter Mars, researchers believe water flowed into the crater, building up and then drying up over and over again. Each time it happened, the sediment carried into the crater by flowing water formed a new layer. Winds that carved the peak of Mount Sharp have exposed these layers and now those layers offer clues about the history of the planet’s climate.

Figuring out when Mars was wet, and for how long, can give scientists an idea of when life may have existed on the planet. If surface conditions were warm enough for liquid water for an extended period of time means that life would have had a chance to take root.

“We went to Gale Crater because it preserves this unique record of a changing Mars,” Caltech’s William Rapin, lead author of the research, said in a statement. “Understanding when and how the planet’s climate started evolving is a piece of another puzzle: When and how long was Mars capable of supporting microbial life at the surface?”

We’re certainly not to a point where we can say that life definitely existed on Mars, but we’re getting closer. When that day comes, studies like this one could tell us what the planet was like for those organisms.


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« Reply #2121 on: Oct 10, 2019, 03:36 AM »


Saturn has 20 new moons, and they all need names

Mike Wehner
BGR
10/10/2019

Earth’s singular moon has offered astronomers the opportunity to study the relationship between planets and the natural satellites that orbit them. In many ways, Earth’s moon is the perfect introduction to teach humanity some very basic things about how the universe works.

There’s no civilization living on the ringed gas giant Saturn, of course, but if there were, they’d have a whole lot more to see when gazing skyward thanks to the planet’s huge collection of moons. Recently believed to be just over 60 in number, a new research effort reveals that there are actually 20 additional moons we had never noticed before, bringing the total to 82.

The new moons were spotted by a team of astronomers using the Subaru telescope, which is part of the Mauna Kea Observatory on Hawaii, and the discovery was announced by the International Astronomical Union’s Minor Planet Center.

It might seem odd that a planet as closely-studied as Saturn could have 20 unknown moons orbiting it, but when you consider the size of these new objects it makes a lot more sense. The moons are tiny by Earth standards, with each pint-sized world measuring only around three miles in diameter. By contrast, Earth’s moon is over 2,158 miles wide.

One particularly interesting note about the newly-discovered moons is that 17 of them orbit Saturn “backwards.” This motion is known as a retrograde orbit, and the fact that many of them appear to be grouped up suggests that their origins are linked to collisions between larger objects in Saturn’s orbit, possibly between ancient Saturn moons or impacts between the moon and other objects, like asteroids.

In a fun bonus, the scientists behind the discovery are now asking for the public’s help in naming the new moons. All 20 moons are up for grabs, and entries should be tweeted to the @SaturnLunacy account, along with photos, artwork, and supporting information to make your case for your name suggestion.


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« Reply #2122 on: Oct 11, 2019, 03:54 AM »

Molten exoplanets may explain the formation of Earth-like worlds

The study of molten exoplanets around Sun-like stars may provide answers as to the formation of Earth-like planets and the evolution of our world.

Rob Lea
ZME
10/11/2019

Researchers from the University of Bern have discovered that the Earth would be approximately 5% larger if it were hot and molten rather than rocky and solid. Pinpointing the difference between rocky exoplanets and their hot, molten counterparts is vital for the search for Earth-like exoplanets orbiting stars outside the solar system.

The fact that rocky exoplanets that are approximately Earth-sized are small in comparison to other planets, makes them notoriously difficult for astronomers to spot and characterise. Identification of a rocky exoplanet around a bright, Sun-like star will likely not be plausible until the launch of the PLATO mission in 2026. Thankfully, spotting Earth-size planets around cooler and smaller stars such as the red dwarfs Trappist-1 or Proxima b is currently possible.

But, searching for molten exoplanets could help astronomers probe the darkness of space — and identify Earth-sized rocky-exoplanets around stars like our own.

    “A rocky planet that is hot, molten, and possibly harbouring a large, outgassed atmosphere ticks all the boxes,” says Dan Bower, an astrophysicist at the Center for Space and Habitability (CSH) of the University of Bern. “Such a planet could be more easily seen by telescopes due to strong outgoing radiation than its solid counterpart.”

Learning more about these hot, molten worlds could also teach astronomers and astrophysicists more about how planets such as our’s form. This is because rocky planets such as the Earth are built from ‘leftovers of leftovers’ — material not utilised in either the formation of stars or giant planets.

    “Everything that doesn’t make its way into the central star or a giant planet has the potential to end up forming a much smaller terrestrial planet,” says Bower: “We have reason to believe that processes occurring during the baby years of a planet’s life are fundamental in determining its life path.”

This drove Bower and a team of colleagues mostly from within the Planet S network to attempt to discover the observable characteristics of such a planet. The resulting study — published in the journal Astronomy and Astrophysics — shows that a molten Earth would have a radius 5% or so larger than the actual solid counterpart. They believe this disparity in size is a result of the differences in behaviour between solid and molten materials under the extreme conditions generated beneath the planet’s surface.

As Bower explains: “In essence, a molten silicate occupies more volume than its equivalent solid, and this increases the size of the planet.”

This 5% difference in radii is something that can currently be measured, and future advances such as the space telescope CHEOPS — launching later this year — should make this even easier.

In fact, the most recent collection of exoplanet data suggests that low-mass molten planets, sustained by intense starlight, may already be present in the exoplanet catalogue. Some of these planets may well then be similar to Earth in regards to the material from which they are formed — with the variation in size no more than the result of the different ratios of solid and molten rock.

Bower explains: They do not necessarily need to be made of exotic light materials to explain the data.”

Even a completely molten planet would fail to explain the observation of the most extreme low-density planets, however. The research team suggest that these planets form as a result of molten planets releasing — or outgassing  — large atmospheres of gas originally trapped within interior magma. This would result in a decrease in the observed density of the exoplanet.

Spotting such outgassed atmospheres of this nature should be a piece of cake for the James Webb Telescope if it is around a planet that orbits a cool red dwarf — especially should it be mostly comprised of water or carbon dioxide.

The research and its future continuation have a broader and important context, points out Bower. Probing the history of our own planet, how it formed and how it evolved.

    “Clearly, we can never observe our own Earth in its history when it was also hot and molten. But interestingly, exoplanetary science is opening the door for observations of early Earth and early Venus analogues that could greatly impact our understanding of Earth and the Solar System planets,” the astrophysicist says. “Thinking about Earth in the context of exoplanets, and vice-versa offers new opportunities for understanding planets both within and beyond the Solar System.”

Original research: Dan J. Bower et al: Linking the evolution of terrestrial interiors and an early outgassed atmosphere to astrophysical observations, Astronomy & Astrophysics. DOI: https://doi.org/10.1051/0004-6361/201935710


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« Reply #2123 on: Oct 12, 2019, 04:10 AM »

Black holes might not be black holes at all

Mike Wehner
BGR
10/12/2019

Of all the features of our universe, black holes might be the most interesting, as well as the most frightening. These ultra-dense spots in space suck in everything around them, and once a black hole has you in its grasp, there’s quite literally no escaping it.

For a long time, scientists have believed that black holes are impossibly tiny dots of incredible mass, called a singularity. This explanation meshes pretty well with our understanding of physics and how objects move an interact in space. But what if black holes are something completely different? A pair of researcher papers published in The Astrophysical Journal argues that point, and if you can wrap your head around it, it’s one heck of an idea.

In some of the most widely-accepted mathematical equations used to explain the expansion of our universe, black holes aren’t factored in. The researchers in this study attempted to make the math of black holes fit within this framework and discovered that the only way it works is if black holes are in fact not singularities at all.

Instead, the scientists suggest that black holes are actually object made of dark energy. They call these hypothetical objects GEODEs (Generic Objects of Dark Energy) and argue that looking at them in this way could answer a number of questions. Specifically, the theory could reveal where dark energy, which scientists believe is contributing to the expansion of the universe, is collected.

GEODEs, the scientists say, would actually get heavier over time as the universe expands, even without slurping up more matter from their surroundings. In some past observations of black holes and black hole mergers, predictions regarding mass have not worked out as expected. If black holes were in fact GEODEs, the math is far easier to work out.

As interesting as this theory is, it’s far from a sure thing. There’s still an incredible amount of observational work that will need to be done before we have a solid idea of what’s going on in those black pits of nothingness in space.


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« Reply #2124 on: Oct 14, 2019, 03:46 AM »


Newly-discovered asteroid could strike Earth within decades

Mike Wehner
BGR
10/14/2019

As technology advances, scientists have become more and more skilled at spotting potentially threatening objects in space. This is great news for the human race, but it also means that when we spot a distant space rock, we may not know just how much of a threat it really is for a long time to come.

That’s the case with asteroid 2019 SU3, a newly-discovered space rock that doesn’t appear dangerous at the moment but may end up being a serious problem several decades down the road. The asteroid, which was just added to the European Space Agency’s Risk List, will make a shockingly close pass of our planet in around 65 years.

Based on observations of the asteroid’s trajectory, the risk of collision is still relatively small, with even the most pessimistic estimates placing the chances of a strike at less than 1%. Still, the fact that the odds aren’t a nice round 0% means that astronomers will need to keep an eye on it.

When the space rock enters our neck of the woods in 2084 it will pass within 6,000 miles of Earth. That might seem like a nice, comfortable distance, but when you consider that Earth’s moon is a whopping 238,000 miles away you get an idea of just how narrow the window truly is.

Generally speaking, mankind has gotten pretty lucky when it comes to asteroids. Humanity hasn’t had to deal with any devastating objects from space, and if we’re lucky we’ll have the technology to deal with those threats before they become a serious problem.

In the coming years, astronomers will be able to increase the certainty of their predictions, and hopefully rule out the possibility that 2019 SU3 poses a threat to our planet. If it does, however, hopefully we’ll be ready.


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« Reply #2125 on: Oct 15, 2019, 03:18 AM »


Former NASA scientists claims we found life on Mars in the 1970s

Mike Wehner
BGR
10/14/2019

NASA’s Viking Project resulted in a pair of successful landings on Mars in 1976, and they were groundbreaking missions in many respects. The spacecraft, which were the first from the US to make a safe landing on the Red Planet, returned images and data from the planet’s surface, and the two landers helped shape future missions to Mars.

Now, a scientist deeply involved in the Viking missions says that if we’re looking for life on Mars, we probably already found it. In a new op-ed, Gilbert Levin, principal investigator of the Viking Labeled Release experiment, says that data sent back from the Mars in the 1970s is proof that life exists on the planet.

The Labeled Release experiment (LR for short) was one of many scientific objectives of the Viking missions. Designed as a way to detect the presence of life on Mars, the tests produced multiple positive results, suggesting microbial activity in the soil of Mars. The results were stunning, but NASA ultimately dismissed them after subsequent experiments failed to find organic matter.

The LR was specifically designed to study the Martian soil for the telltale signs that microbes were present. Microbes “breath” and by detecting those signatures in the soil, the scientists involved in the experiment believed they had made a monumental discovery.

“The data curves signaled the detection of microbial respiration on the Red Planet,” Levin writes. “The curves from Mars were similar to those produced by LR tests of soils on Earth. It seemed we had answered that ultimate question.”

However, a separate experiment to detect the presence of organic matter came up empty-handed, leaving NASA to conclude that the signatures found in the soil of Mars were the result of some other process, and that the LR’s results were not proof of life. Levin strongly disagrees, and lays out his argument and supporting evidence nicely.

In the years since the Viking missions, NASA’s rovers and landers have returned data that may support the idea of past or present life on Mars. The presence of water, organic compounds, rapidly-changing methane concentrations, and several other discoveries all seem to point in that direction, but NASA maintains there’s no indisputable evidence… yet.

Levin argues that NASA should make the detection of microbial life a top priority in future missions, and suggests that the agency’s refusal to include life-detection experiments on its recent missions is shortsighted. The Mars 2020 lander is not expected to include any such experiments.


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« Reply #2126 on: Oct 16, 2019, 04:06 AM »


Newly-discovered interstellar object is spewing cyanide gas

Mike Wehner
BGR
10/16/2019

Astronomers spotted an interstellar object passing through our solar system last month. It was only the second time scientists have ever detected such an object, and after some intense investigation, the object — now believed to be a comet or comet-like body — was documented and named for the amateur astronomer who first spotted it.

The comet, called 2I/Borisov, was spotted relatively early in its trip through our system, giving scientists plenty of time to observe it. The first round of studies is already returning some interesting findings, including the fact that the object is dumping cyanogen gas (gas that is at least partly made up of cyanide) as it speeds through our home system.

A new paper published in Astrophysical Journal Letters reveals that interesting finding, which was made thanks to data gathered by an international team of scientists using the William Herschel Telescope. But as seemingly frightening as this discovery seems on the surface, there’s very little to worry about for us here on Earth.

“Interstellar objects are samples of materials from other planetary systems, delivered to our doorstep—or at least to our own solar system,” Professor Alan Fitzsimmons, who led the research, told Universe Today. “The physical nature gives us clues as to how other planetary systems evolve, and the types of small bodies that may exist there. Measuring their composition allows us to compare what we find with decades of studies of comets and asteroids orbiting the sun.”

Fitzsimmons says that while this particular comet appears a bit more “gassy” than the kinds of comets we typically see in our system, the fact that it contains cyanide isn’t particularly shocking.

2I/Borisov’s trajectory has already been plotted and it doesn’t seem that the object will come anywhere near Earth, or even pass through Earth’s orbital path around the Sun, so there’s virtually zero chance any of the comet material will find its way to our planet.

Scientists will continue to observe the object as it gradually passes through our system, and the comet should remain visible for many months to come. You can expect to hear a lot more about it as various research efforts get underway.


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« Reply #2127 on: Oct 17, 2019, 03:17 AM »

Some water ice on the Moon is billions of years old — and colonists could drink it all up

Bottoms up!

Alexandru Micu
ZME
10/17/2019

The viability and eventual success of long-term manned missions to the moon depend heavily on us locating a source of water up there. Water on the moon would allow astronauts to live on the moon much longer and for cheaper (which matters a lot when trying to get funding out of politicians) than if they had to ship it up from Earth.

The local drink

Recent research has shown that there may be water ice in the craters near the moon’s poles, and even traces of liquid water across its surface. However, until we understand how this water got there, we won’t have much success predicting where it will be found. A new study looking into the issue reports that lunar ice deposits could have multiple sources, some being more recent while others could be billions of years old.

The team used data on craters near the moon’s south pole, where evidence of water had been previously discovered, recorded by the Lunar Reconnaissance Orbiter. The researchers looked at the age of these craters, and report that any ice they contain couldn’t be older than 3.1 billion years. The ice deposits, the team explains, come in patches across the floor of individual craters, suggesting that they have been exposed to impacts by small meteorites over a long period of time.

The researchers used data from the Lunar Reconnaissance Orbiter to look at craters near the south pole where evidence of water has been found. They analyzed the age of these craters and found that the ice within them could not be older than 3.1 billion years. More evidence for the age of the ice comes from the patterns of deposits, which are patchy across the floor of the crater. This suggests the deposits have been impacted by small meteorites over a long period of time.

Most of the ice deposits seem to be quite ancient. Some of them, the team adds, especially those in smaller craters with sharper edges, appear to be the most recent. The authors say this is quite a surprise as “hadn’t really been any observations of ice in younger cold traps before,” Brown University researcher Ariel Deutsch explained in a statement.

    “There have been models of bombardment through time showing that ice starts to concentrate with depth. So if you have a surface layer that’s old, you’d expect more underneath,” Deutsch adds.

The study fleshes out our understanding of resource availability on the moon, knowledge which can make or break future long-term missions.

    “When we think about sending humans back to the Moon for long-term exploration, we need to know what resources are there that we can count on, and we currently don’t know,” co-author of the study, Professor Jim Head of Brown University, said in the same statement.

    “Studies like this one help us make predictions about where we need to go to answer those questions.”

Along with other recent research looking into how lunar soil (‘regolith’) can be turned into breathable oxygen and raw metal for would-be colonists, the present findings suggest that the moon would be a much more bountiful place to live than we assumed up to now.

The paper “Analyzing the ages of south polar craters on the Moon: Implications for the sources and evolution of surface water ice” has been published in the journal Icarus


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« Reply #2128 on: Oct 18, 2019, 03:30 AM »

Colonizing Mars could be accelerated with microbes, study suggests

The idea challenges the strict no-contamination guidelines that NASA and all space programs have closely adhered to for decades.

Fermin Koop byFermin Koop
ZME
10/18/2019

Colonizing Mars has been a growing objective of humanity over recent years. But doing so could mean landing a containment of microorganisms on the planet, according to a new study.
Credit: Wikipedia Commons

A paper published in the journal FEMS Microbiology Ecology argued that the “primary colonists” of the Red Planet should be “microorganisms” – the bacteria, viruses, and fungi that support many of life’s processes here on Earth.

Jose Lopez, a professor at Nova Southeastern University and one of the authors of the paper, proposed an approach to the colonization of Mars that relies on microbes that could support life in extraterrestrial environments.

    “Life as we know it cannot exist without beneficial microorganisms,” he said in a statement. “To survive in a barren (and as far as all voyages to date tell us) sterile planet, we will have to take beneficial microbes with us.”

The idea challenges the strict no-contamination guidelines that NASA and all space programs have closely adhered to for decades. When it comes to the equipment being sent off to space, typically everything is carefully sterilized and protected from germs and contaminants.

Lopez and the research team argued that introducing helpful microbes could actually kickstart the process of terraforming Mars and sustaining life on the Red Planet. The microbial introduction should not be considered accidental but inevitable, reads the paper.

Back on Earth, microorganisms are critical to many of the processes that sustain life, such as decomposition and digestion. The paper claimed that the best microbes for the job might be extremophiles — organisms that are hyper tolerant of the most extreme environments, and even thrive in them, like tardigrades.

The paper argued for a change in attitude toward microbes in space, viewing them as beneficial versus dangerous. But researchers still don’t know which microbes would help rather than hurt efforts to terraform Mars. Space agencies need to start work now on developing the right kind of organisms to send over.

Everyone from Elon Musk to Jeff Bezos to NASA needs to make a “provocative paradigm shift” in our policies for space colonization, Lopez claimed.

    “This will take time to prepare, discern,” Lopez said. “We are not advocating a rush to inoculate, but only after rigorous, systematic research on earth.”


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« Reply #2129 on: Oct 19, 2019, 04:15 AM »


Nasa astronauts complete first ever all-female spacewalk

Christina Koch and Jessica Meir, tasked with replacing faulty device at International Space Station, embarked on ‘historic’ effort

Hannah Devlin Science correspondent
Guardian
Sat 19 Oct 2019 00.43 BST

Two Nasa astronauts have embarked on the first all-female space walk in a historic first.

Christina Koch and Jessica Meir floated feet-first out of the International Space Station’s (ISS) Quest airlock on Friday lunchtime UK time, tasked with replacing a failed power control unit.

The spacewalk, known as an extra-vehicular activity (EVA) in astronaut jargon, took place seven months after the original planned date for an all-female outing, which had to be scrapped because the ISS had only one medium-sized spacesuit on board. The agency sent up a second medium spacesuit in October.

“I think it’s important because of the historical nature of what we’re doing,” Koch said ahead of the spacewalk. “In the past, women haven’t always been at the table. It’s wonderful to be contributing to the space program at a time when all contributions are being accepted, when everyone has a role. That can lead in turn to increased chance for success.”

Koch, who has been on the ISS since March, was first out the hatch, followed by Meir, carrying a tool bag. During the five-and-a-half-hour spacewalk, the astronauts remained attached to handrails on the exterior of the ISS using harnesses and pairs of metal carabiners. These are sequentially clipped and unclipped to ensure that the astronauts cannot float off into space.

Video footage from the astronauts’ helmet cameras, as they dangled 260 miles above Earth, provided a live stream of the painstaking operation to carry the new hardware, install it and then return the faulty battery to the airlock for a postmortem back on Earth into why it failed.

Tracy Caldwell Dyson, a Nasa astronaut who completed three spacewalks as part of the Expedition 24 crew on the ISS in 2010, said: “This is significant … As much as it’s worth celebrating, many of us are looking forward to it just being normal.”

During the spacewalk, the coordinator on the ground was Stephanie Wilson, also an astronaut.

Koch, 40, is due to remain on the ISS until February, bringing her total time in space to 328 days, the longest single spaceflight by a woman and just short of Scott Kelly’s 340-day record. Researchers are collecting extensive biomedical data on the impact of spaceflight on Koch’s body.

The majority of data available is on male astronauts, but there is some evidence that there are sex differences in responses to a space environment. One study found that women are more likely than men to experience faintness as a result of “orthostatic hypotension”, a cardiovascular issue. Men appear more prone to vision changes caused by spaceflight associated neuro-ocular syndrome (Sans).

Previously, 14 women and 213 men have carried out spacewalks. The first woman was the Russian cosmonaut Svetlana Savitskaya, who went outside the USSR’s Salyut 7 space station in 1984.

On Tuesday, Nasa unveiled the prototype for a new spacesuit that could be worn by the next crew, expected to include a woman, to land on the moon. The suit is designed to give a customised fit to the individual astronaut, whatever their shape or size.

Watch: https://www.youtube.com/watch?v=DZvfPt_gt0s


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