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The Lounge>Science is Cool....
Fish 09:43 PM 05-21-2012
This is a repository for all cool scientific discussion and fascination. Scientific facts, theories, and overall cool scientific stuff that you'd like to share with others. Stuff that makes you smile and wonder at the amazing shit going on around us, that most people don't notice.

Post pictures, vidoes, stories, or links. Ask questions. Share science.

This is in support of the Penny 4 NASA project. If you enjoy anything you learned from this thread, consider making a donation and signing the petition.

Why should I care?:

Fish 10:00 PM 10-09-2019
Hey ladies... lesbian scissoring is good for you and scientifically encouraged...
BigRedChief 08:28 AM 10-12-2019

Otter 08:47 AM 11-04-2019

stumppy 09:14 AM 11-04-2019
Originally Posted by Otter:
DaFace 03:47 PM 11-08-2019
For those interested...

"COSMOS: Possible Worlds"
Premiere: March 9, 2020@NatGeoChannel

Be there.

— Neil deGrasse Tyson (@neiltyson) November 8, 2019

Chiefs4TheWin 07:48 PM 11-08-2019
Originally Posted by DaFace:
For those interested...

I'm in.
Fish 08:17 PM 11-08-2019
Weird Object: Neutron Star PSR J1748-2446

What is PSR J1748–2446’s claim to weirdness fame? Simple. It’s the universe’s fastest-spinning celestial object. It’s also a star whose surface is not just solid, but harder than a diamond. Its density is 50 trillion times greater than lead. Its magnetic field sizzles a trillion times more intensely than our Sun’s. In a nutshell, it’s the most extreme example of a neutron star.

A neutron star forms when the core of a heavy sun, with the mass of about a few million Earths, collapses into a tiny sphere while the rest of its body hurtles outward during a supernova explosion. When this occurs, the inverse-square law of gravity goes into its demo-mode with a vengeance. Because this star no longer has a fusion generator, and thus no outward-pushing pressure to keep it from collapsing, gravity has a free hand. When the collapsing star gets five times smaller, its inward-pulling surface gravity becomes 25 times fiercer. When the star shrinks to 100 times smaller than it was before, its surface gravity now sucks inward with 100 x 100 (i.e., 10,000) times more force — and it keeps going. The smaller the star becomes, the more violent its collapse.

Normal 1-solar-mass stars stop collapsing when they’re the size of Earth. Then, electron degeneracy pressure halts the show because each electron needs a bit of breathing room. But if a star’s mass is more than 1.4 Suns — the famous Chandrasekhar limit — as PSR J1748–2446 originally was, then electrons get squeezed into the protons and the collapse continues. At this point, the previously separate atomic particles lose their identities. Everything becomes a neutral ocean of ultra-dense goo, and a few million Earths now pack into a ball less than 20 miles (30 kilometers) wide — a star that could barely cover Los Angeles.

Its spin ratchets up, too, like an over-caffeinated ballerina. Such collapsed stars often rotate 20, 30, or even 100 times a second. But if a neutron sun has a companion star as this one does, then newly captured material can speed it up further still. PSR J1748–2446 spins 716 times every second!

It’s hard to visualize. In everyday life, the fastest-spinning thing we might see is the blade on a kitchen blender or a circular saw. But those never rotate more than a few hundred times a second. This star’s equator moves at one-quarter the speed of light. This rotation of 43,000 miles (70,000km) per second would be like Earth’s equator completing nearly two spins a second instead of one a day.

Imagine living there. Taxes would be very low, but there’d also be several significant drawbacks. The gravity would crush you down so that your protoplasm would spread itself evenly around the surface like a film of oil. You couldn't stand more than one atom high. But if you could still somehow remain conscious, you’d see every star in the sky cross the heavens from horizon to horizon in less than a thousandth of a second, each appearing as a solid line. Studying the cosmos might be a challenge.

Indeed, PSR J1748–2446 rotates about as rapidly as possible. If it went any faster, it would fling its material into space like whipped cream tossed into a fan.

Similar to a lighthouse, neutron stars deliver quick bursts of energy with every turn, and PSR J1748–2446 releases a consistent ultra-quick series of flashes in a wide range of wavelengths. Indeed, Jason Hessels of McGill University in Montreal, Canada, first detected this object at radio frequencies in 2004. Visually, its light looks steady because nobody can differentiate so many flashes per second, which is 30 times faster than those from a movie projector.
The only visible object that could theoretically surpass the density of this crushed “superball” is a “quark star.” In 2002, researchers announced finding exactly such an object, but it was soon rejected by nearly the entire astrophysical community, which faulted the evidence. So the record stands today.

This fastest-ever pulsar is parked in a globular cluster of stars in Sagittarius the Archer, 18,000 light-years away, in the direction of our galaxy’s center. Called Terzan 5, the cluster is hard to see because foreground dusty gas heavily obscures it. In fact, Terzan 5 is itself quite unusual, having a higher star concentration than any other cluster and also housing stars born in different periods. Some think this cluster is actually the remnant of a dwarf galaxy cannibalized by our Milky Way.

PSR J1748–2446 is also weird because it is part of a binary star system. Its companion is a swollen giant that nonetheless contains just one-seventh our Sun’s mass; this pair whirls around each other in a perfectly circular orbit every 26 hours. Doing so, the companion passes in front of the pulsar daily, blocking 40 percent of its light. This adds a precise clockwork dimming to its ultra-fast flashes, making it simultaneously variable in two different ways.

The whole thing just gets curioser and curioser.
Fish 08:18 PM 11-08-2019

Fish 08:19 PM 11-08-2019
Also... regarding that Kora borehole on the far right of the above pic....

Fish 06:15 PM 11-21-2019
That's crazy to think about.

The Most Remote Place On Earth

Point Nemo is officially known as “the oceanic pole of inaccessibility,” or, more simply put, the point in the ocean that is farthest away from land. Located at 48°52.6′S 123°23.6′W, the spot is quite literally the middle of nowhere, surrounded by more than 1,000 miles of ocean in every direction. The closest landmasses to the pole are one of the Pitcairn islands to the north, one of the Easter Islands to the northeast, and one island off of the coast of Antarctica to the south.

Clearly, there are no human inhabitants anywhere near Point Nemo (the name “Nemo” itself is both Latin for “no one,” as well as a reference to Jules Verne’s submarine captain from 20,000 Leagues Under The Sea). In fact, the location is so isolated that the closest people to Nemo are actually not even on Earth. The astronauts aboard the International Space Station are around 258 miles from their home planet at any given time. Since the inhabited area closest to Point Nemo is more than 1,000 miles away, the humans in space are far closer to the pole of inaccessibility than those on land.

Not even the man who discovered Point Nemo has ever visited it. In 1992, survey engineer Hrvoje Lukatela located the point in the ocean that was farthest away from any land using a computer program that calculated the coordinates that were the greatest distance from three equidistant land coordinates. It is very possible no human has ever passed through those coordinates at all.

As for non-human inhabitants, there aren’t very many of those around Point Nemo either. The coordinates are actually located within the South Pacific Gyre: an enormous rotating current that actually prevents nutrient-rich water from flowing into the area. Without any food sources, it is impossible to sustain any life in this part of the ocean (other than the bacteria and small crabs that live near the volcanic vents on the seafloor).

Because Point Nemo is located in what has been described as “the least biologically active region of the world ocean,” scientists were surprised when, in 1997, they detected one of the loudest underwater sounds ever recorded near the pole.

The sound was captured by underwater microphones more than 3,000 miles apart. Befuddled scientists at the National Oceanic and Atmospheric Administration were at a loss to think of something large enough to create such a loud sound underwater and dubbed the mystery noise “The Bloop.” Sci-fi enthusiasts, however, quickly thought of one explanation.

When writer H.P. Lovecraft first introduced readers to his infamous titular, tentacled monster in 1926’s “The Call of Cthulhu,” he wrote that the creature’s lair was the lost city of R’yleh in the south Pacific Ocean. Lovecraft gave R’yleh the coordinates 47°9′S 126°43’W, which are astonishingly close to those of Point Nemo and to where The Bloop was recorded. The fact that Lovecraft first wrote about his sea monster in 1928 (nearly a full 50 years before Lukatela calculated Nemo’s location) led some people to speculate that the pole of inaccessibility was, in fact, home to a yet-undiscovered creature of some sorts.

As it turns out, The Bloop was actually the sound of ice breaking off of Antarctica and not the call of Cthulhu. Point Nemo does, however, have at least one other eerie claim to its name. Due to its remoteness and distance from shipping routes, the area around Nemo was chosen as a “spaceship graveyard.”

Because autonomous spaceships are not designed to survive re-entry into Earth’s atmosphere (the heat usually destroys them), scientists needed to select an area where there would be an extremely low risk of any humans being struck with flying space-debris. With a population of zero, the oceanic pole of inaccessibility at Point Nemo offered the perfect solution.
Fish 06:19 PM 11-21-2019

First Detection of Sugars in Meteorites Gives Clues to Origin of Life

An international team has found sugars essential to life in meteorites. The new discovery adds to the growing list of biologically important compounds that have been found in meteorites, supporting the hypothesis that chemical reactions in asteroids – the parent bodies of many meteorites – can make some of life’s ingredients. If correct, meteorite bombardment on ancient Earth may have assisted the origin of life with a supply of life’s building blocks.

The team discovered ribose and other bio-essential sugars including arabinose and xylose in two different meteorites that are rich in carbon, NWA 801 (type CR2) and Murchison (type CM2). Ribose is a crucial component of RNA (ribonucleic acid). In much of modern life, RNA serves as a messenger molecule, copying genetic instructions from the DNA molecule (deoxyribonucleic acid) and delivering them to molecular factories within the cell called ribosomes that read the RNA to build specific proteins needed to carry out life processes.

“Other important building blocks of life have been found in meteorites previously, including amino acids (components of proteins) and nucleobases (components of DNA and RNA), but sugars have been a missing piece among the major building blocks of life,” said Yoshihiro Furukawa of Tohoku University, Japan, lead author of the study published in the Proceedings of the National Academy of Sciences November 18. “The research provides the first direct evidence of ribose in space and the delivery of the sugar to Earth. The extraterrestrial sugar might have contributed to the formation of RNA on the prebiotic Earth which possibly led to the origin of life.”

“It is remarkable that a molecule as fragile as ribose could be detected in such ancient material,” said Jason Dworkin, a co-author of the study at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “These results will help guide our analyses of pristine samples from primitive asteroids Ryugu and Bennu, to be returned by the Japan Aerospace Exploration Agency’s Hayabusa2 and NASA’s OSIRIS-REx spacecraft.”

An enduring mystery regarding the origin of life is how biology could have arisen from non-biological chemical processes. DNA is the template for life, carrying the instructions for how to build and operate a living organism. However, RNA also carries information, and many researchers think it evolved first and was later replaced by DNA. This is because RNA molecules have capabilities that DNA lacks. RNA can make copies of itself without “help” from other molecules, and it can also initiate or speed up chemical reactions as a catalyst. The new work gives some evidence to support the possibility that RNA coordinated the machinery of life before DNA.

“The sugar in DNA (2-deoxyribose) was not detected in any of the meteorites analyzed in this study,” said Danny Glavin, a co-author of the study at NASA Goddard. “This is important since there could have been a delivery bias of extraterrestrial ribose to the early Earth which is consistent with the hypothesis that RNA evolved first.”

The team discovered the sugars by analyzing powdered samples of the meteorites using gas chromatography mass spectrometry, which sorts and identifies molecules by their mass and electric charge. They found that the abundances of ribose and the other sugars ranged from 2.3 to 11 parts per billion in NWA 801 and from 6.7 to 180 parts per billion in Murchison.

Since Earth is awash with life, the team had to consider the possibility that the sugars in the meteorites simply came from contamination by terrestrial life. Multiple lines of evidence indicate contamination is unlikely, including isotope analysis. Isotopes are versions of an element with different mass due to the number of neutrons in the atomic nucleus. For example, life on Earth prefers to use the lighter variety of carbon (12C) over the heavier version (13C). However, the carbon in the meteorite sugars was significantly enriched in the heavy 13C, beyond the amount seen in terrestrial biology, supporting the conclusion that it came from space.

The team plans to analyze more meteorites to get a better idea of the abundance of the extraterrestrial sugars. They also plan to see if the extraterrestrial sugar molecules have a left-handed or right-handed bias. Some molecules come in two varieties that are mirror images of each other, like your hands. On Earth, life uses left-handed amino acids and right-handed sugars. Since it’s possible that the opposite would work fine – right-handed amino acids and left-handed sugars – scientists want to know where this preference came from. If some process in asteroids favors the production of one variety over the other, then maybe the supply from space via meteorite impacts made that variety more abundant on ancient Earth, which made it more likely that life would end up using it.
Fish 06:33 PM 11-21-2019
Probably these:

NASA’s Curiosity Rover Finds Unexplained Oxygen on Mars
Fluctuating levels of the atmospheric gas, a potential tracer of alien life, have left researchers mystified

NASA’s Curiosity rover, for three Martian years—nearly six years to us Earthlings—has been sniffing the air above Mars’ Gale Crater, its near-equatorial exploration site. Using its Sample Analysis at Mars (SAM) portable chemistry lab, the rover has ascertained not only what the surface atmosphere is made of, but also how its gases change with the seasons.

Many of Mars’ gases “are very well behaved,” says Melissa Trainer, a planetary scientist at NASA and a team member on the SAM experiment. One, however, appears to be behaving in a decidedly unexpected and altogether bizarre manner: oxygen.

Scientists have long known that carbon dioxide on Mars, which makes up 95 percent of the planet’s atmosphere, freezes out over the poles in winter, and sublimates back into a gas in summer. In the thin air around Gale Crater, Curiosity’s measurements have shown tiny amounts of inert argon and nitrogen periodically rising and falling as expected, due to this seasonal cycling of carbon dioxide.

Curiosity’s instruments also registered atmospheric oxygen rising and falling at similar times but in amounts that defy easy explanation. There was far more of it during the spring and summer, and less of it in the winter, than the seasonal whooshing back and forth of other gases would predict.

That suggests something is making or unleashing stores of oxygen in the warmer months and trapping or swallowing it up during frigid ones. It could be a geological, chemical, atmospheric or, perhaps even a biological process, but right now, no one has the foggiest as to what the culprit actually is. And although the oxygen’s trampolining certainly appears to be a local feature, it might be a regional or even global peculiarity.

François Forget, a planetary scientist at the French National Center for Scientific Research, says that this finding is surprising, weird and mysterious. Jon Telling, a geochemist and geomicrobiologist at Newcastle University, says he and other experts are understandably “flummoxed.”

An unanticipated challenge has suddenly been laid out before the scientific community. It is unclear when, or even if, the case of the overzealous oxygen will be cracked. Already, says Paul Niles, a planetary geologist and analytical geochemist at NASA, it is abundantly clear that “Mars is a lot more alien than we thought.”

In situ measurements of the pressure, temperature and composition of Mars’ atmosphere date back nearly a half century, from the Viking landers in the 1970s through to the Spirit, Opportunity and now Curiosity rovers. Curiosity’s SAM suite, however, has painstakingly tracked how Martian atmospheric gas amounts change through the seasons, thereby providing scientists with a game-changing, precise chronicle of the planet's atmosphere.

Oxygen’s too-high spikes and too-low nadirs during the warmer and colder months, respectively, came as a shock. Curiosity’s scientists could conceive of only two possibilities: either a mysterious creator and destroyer of oxygen existed on Mars that scientists were unaware of, or the measurements were wrong. Trainer, lead author of the study reporting the discovery in the Journal of Geophysical Research: Planets, emphasizes that this detection and analysis took many years, with all possible false positive triggers ruled out.

“I think they’ve done their due diligence,” Niles says. Plenty can go wrong with these interplanetary science experiments, from equipment malfunctions to contamination. Regardless, he says, “I don’t see any reason to have any doubt in the oxygen measurements.”

“I hope it’s real,” Forget says, because an extraterrestrial oxygen enigma is far more fun than a glitch.

A true enigma would force researchers to go back to basics, says Manish Patel, a planetary scientist at the Open University. “We must first interrogate our understanding of the known processes for creating oxygen, before we invoke any new, or controversial, processes.”

Trainer and her colleagues did just that. But they still came up short. Solar radiation could be breaking up oxygen molecules and blowing them away into space, but this process appears to be too slow and inefficient to account for the seasonal dips seen by Curiosity. Perhaps carbon dioxide’s slow breakdown in the atmosphere could have released oxygen, causing a summertime spike—but again, this process would take too long to produce the observed peaks.

Martian soil is rich in oxygen-containing hydrogen peroxide and perchlorates. The Viking landers demonstrated that warm, damp air could free this oxygen, but those conditions do not prevail across enough of the planet—let alone Gale Crater—to suffice for the SAM data. Soil bombardment by ionizing radiation from cosmic rays and solar storms might do the trick, but is estimated to require a million years to create the oxygen peak seen during one solitary spring.

We simply do not know enough about Mars to get a grip on this particular puzzle, says Niles. So much about its chemistry—how gases are transported above and within the planet, what sources and sinks they may have—remains deeply uncertain. For all we know, he says, events in Mars’ past could have conspired to lock away vast amounts of oxygen belowground, which is now, for some reason, surging back into the atmosphere.

If the answer is not to be found in Mars’ lifeless air and rocks, could some cryptic, alien form of biology be to blame? On Earth, photosynthesis and respiration by living things cause tiny fluctuations in our planet’s otherwise steady oxygen concentration. We shouldn’t expect this on Mars, though. “That’s far out,” Telling says: Mars appears too inhospitable for a critical mass of life capable of sustaining either process. “It’s almost certainly going to be a nonbiological chemical reaction.”

Trainer herself does not rule out a biological explanation, but nevertheless underscores its unlikeliness. “People in the community like to say that it will be the explanation of last resort, because that would be so monumental,” she says. There are abiotic mechanisms aplenty, both known and unknown, to rule out first before leaping to any more sensational claims.

BigRedChief 09:21 AM 11-22-2019
Maybe a more efficent way to deliver electricity?

listopencil 05:22 AM 12-05-2019
Um...oh, shit:

Scientists worried by thousands of tardigrades crash-landing on the moon: ‘We have no idea what can happen’

The Beresheet lunar lander mission on April 11 was historic: Funded and deployed by Space IL, it was the first Israeli spacecraft to travel beyond Earth’s orbit and the first private landing on the Moon. Unfortunately for SpaceIL, things didn’t go as planned: Seconds before Beresheet (Hebrew for “beginning”) was supposed to land, it lost contact with the control room. During the braking procedure, the main engine stopped operating. By the time it was brought back online, it was too late for a soft landing and Beresheet crashed onto the surface. On board was a “lunar library” created by the Arch Mission Foundation as kind of time capsule for the combined knowledge of human civilization. The library contained samples of human DNA and 30 million pages of digital and analog data, including a full copy of Wikipedia, an Israeli flag, a Torah and a copy of the Israeli Declaration of Independence.

It also housed thousands of tardigrades—microscopic eight-legged animals also known as “water bears.”
Fish 08:05 AM 12-05-2019
It was 2119. The Great Moon Tardigrade Invasion had begun. Mankind was not prepared....

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