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An asteroid will head towards Earth right before the US election: NASA | Mapped – Daily Hive

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An Earth-rattling mass is headed towards the planet in November, and it’s not Donald Trump.

According to the Center for Near Earth Objects Studies (CNEOS) at NASA’s Jet Propulsion Laboratory, an asteroid is projected to zoom pretty close to Earth on November 2, the day before the 2020 US presidential election.

The asteroid, known as 2018VP1, was first identified at the Palmor Observatory in San Diego County in 2018. It’s expected to be anywhere between 1.8 metres to 3.9 metres in diameter and has a 0.41 percent chance of actually making contact with our planet.

Asteroids are small rock-like objects that orbit the sun. NASA says asteroids can range in size from that of a pebble to ones that are measured in hundreds of miles in diameter.

Asteroids orbiting around the solar system is not uncommon. In fact, a car-sized asteroid made its closest-known approach to Earth earlier in August when it zoomed by the planet without researchers even knowing until hours after it had passed.

NASA says Asteroid 2020 QG (formerly known as ZTFoDxQ) flew by Earth on August 15 at 12:08 am EDT, getting as close as 2,945 kilometres away. According to NASA, it was the closest an asteroid flyby has ever been recorded to Earth.

The CNEOS says the chance of November’s 2018VP1 striking Earth is very unlikely, but considering everything we’ve gone through already in 2020, would anyone really be that surprised?

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A physicist says new math proves paradox-free time travel is possible – SlashGear

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Time travel has been the staple science fiction books and movies for many years. Most who have read or watched content focusing on time travel knows about the paradox issue. Perhaps the best example is the 80s classic “Back to the Future,” where Marty accidentally prevents his parents from meeting and has to fix his error before he’s wiped out of existence.

Time travel is something that scientists and physicists have considered for many years. A physics student named Germain Tobar from the University of Queensland in Australia says that he has figured out the math that would make time travel viable without paradoxes. According to Tobar, classical dynamics says if you know the state of the system at a particular time, it can tell you the entire history of the system.

His calculations suggest that space-time may be able to adapt itself to avoid paradoxes. One example is a time traveler who journeys into the past to stop a disease from spreading. If the mission were successful, there would’ve been no disease for the time traveler to go back and try and prevent. Tobar suggests that the disease would still spread in some other way, through different route or method, removing the paradox.

He says whatever the time traveler did, the disease wouldn’t be stopped. Tobar’s work is highly complicated but is essentially looking at deterministic processes on an arbitrary number of regions in the space-time continuum. It’s demonstrating how closed timelike curves, which Einstein predicted, can fit in with the rules of free will and classical physics.

Tobar’s research supervisor is physicist Fabio Costa from the University of Queensland. Costa says that the “maths checks out,” further noting that the results are the stuff of science fiction. The new math suggests that time travelers can do what they want, and paradoxes are not possible. Costa says that events will always adjust themselves to avoid any inconsistency.

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We May Finally Know What Life on Earth Breathed Before There Was Oxygen – ScienceAlert

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Billions of years ago, long before oxygen was readily available, the notorious poison arsenic could have been the compound that breathed new life into our planet.

In Chile’s Atacama Desert, in a place called Laguna La Brava, scientists have been studying a purple ribbon of photosynthetic microbes living in a hypersaline lake that’s permanently free of oxygen.

“I have been working with microbial mats for about 35 years or so,” says geoscientist Pieter Visscher from the University of Connecticut.

“This is the only system on Earth where I could find a microbial mat that worked absolutely in the absence of oxygen.”

Microbial mats, which fossilise into stromatolites, have been abundant on Earth for at least 3.5 billion years, and yet for the first billion years of their existence, there was no oxygen for photosynthesis.

How these life forms survived in such extreme conditions is still unknown, but examining stromatolites and extremophiles living today, researchers have figured out a handful of possibilities. 

While iron, sulphur, and hydrogen have long been proposed as possible replacements for oxygen, it wasn’t until the discovery of ‘arsenotrophy‘ in California’s hypersaline Searles Lake and Mono Lake that arsenic also became a contender.

Since then, stromatolites from the Tumbiana Formation in Western Australia have revealed that trapping light and arsenic was once a valid mode of photosynthesis in the Precambrian. The same couldn’t be said of iron or sulphur.

Just last year, researchers discovered an abundant life form in the Pacific Ocean that also breathes arsenic. 

Even the La Brava life forms closely resemble a purple sulphur bacterium called Ectothiorhodospira sp., which was recently found in an arsenic-rich lake in Nevada and which appears to photosynthesise by oxidising the compound arsenite into a different form -arsenate.

While more research needs to verify whether the La Brava microbes also metabolise arsenite, initial research found the rushing water surrounding these mats is heavily laden with hydrogen sulphide and arsenic.

If the authors are right and the La Brava microbes are indeed ‘breathing’ arsenic, these life forms would be the first to do so in a permanently and completely oxygen-free microbial mat, similar to what we would expect in Precambrian environments.

As such, its mats are a great model for understanding some of the possible earliest life forms on our planet. 

While genomic research suggests the La Brava mats have the tools to metabolise arsenic and sulphur, the authors say its arsenate reduction appears to be more effective than its sulfate reduction.

Regardless, they say there’s strong evidence that both pathways exist, and these would have been enough to support extensive microbial mats in the early days of life on Earth.

If the team is right, then we might need to expand our search for life forms elsewhere.

“In looking for evidence of life on Mars, [scientists] will be looking at iron and probably they should be looking at arsenic also,” says Visscher.

It really is so much more than just a poison.

The study was published in Communications Earth and Environment

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Hope for life on Venus survives for centuries against all odds – Finance Brokerage

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If you’re looking for an exemplar of mastering multiple identities, find a telescope and point it at Venus.

In both astronomy and popular culture, Venus has always assumed a diversity of guises. Morning star, evening star. Goddess. Planet. Frankie Avalon song. A plant that eats flies. And the realm ruled by women in the unforgettable film Queen of Outer Space (starring Zsa Zsa Gabor as the nemesis of the evil queen).

So it’s not surprising that Venus enjoys sufficient celebrity status to warrant big-type headlines when it makes news, or at least a lot of social media hype. In the latest such instance, all it took was a whiff of a noxious gaseous chemical in the planet’s clouds, hinting that Venus might harbor life, to stop the presses and start the tweetstorms. After all, life on Venus would be a big surprise. Scientists have long considered it the hell of the solar system, hotter than molten lead and with an unbreathable atmosphere.

Yet, as it was so ably reported by Lisa Grossman for Science News, the chemical in question, phosphine, is no guarantee of life on Venus. It’s just that the known nonbiologic ways to make phosphine do not seem plausible in the Venusian environment. Phosphine’s persistence in the clouds shrouding Venus suggests something must be currently producing it — otherwise the sulfuric acid in the planet’s upper atmosphere would have destroyed any signs of the gas by now. So phosphine might be a signal of life — perhaps some form of anaerobic bacteria (which do not require oxygen), as phosphine would be deadly to life that relied on oxygen.

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On the other hand, maybe there’s just a gap in Earthling chemistry textbooks, and some weird geochemical reactions produce Venusian phosphine. That’s probably a better bet than airborne anaerobic alien organisms. Phosphine as evidence of life on Venus may turn out to be as reliable as the famous “canals” once regarded as evidence for life on Mars.

Still, hope for life on Venus never dies. In centuries past, in fact, many scientists simply assumed that Venus possessed life. In the late 17th century, Bernard le Bovier de Fontenelle, a French popularizer of science, surmised Venus to be inhabited by a gallant race of lovers. “The climate is most favorable for love matches,” he wrote. About the same time, the Dutch physicist and astronomer Christiaan Huygens contemplated life on Venus. Venusians would receive twice the light and heat from the sun as Earthlings do, he knew, but noted that Earth’s tropics, though much hotter than northern lands, are successfully occupied by people. For that matter, Huygens believed much hotter Mercury to be populated as well, and that the Mercurians would no doubt consider Earth much too cold and dark to support life.

In the 19th century, spectroscopic examination of Venus suggested that its atmosphere was similar to Earth’s, containing water vapor and oxygen. Since Earth’s atmospheric composition owed so much to life, it seemed obvious that life — at least plants— must exist on Venus as well. “If there be oxygen in the atmosphere of Venus, then it would seem possible that there might be life on that globe not essentially different in character from some forms of life on the earth,” astronomer Robert S. Ball wrote in his widely read late 19th century book The Story of the Heavens. “If water be present on the surface of Venus and if oxygen be a constituent of its atmosphere, we might expect to find in that planet a luxuriant tropical life.”

As late as 1918, Svante Arrhenius, a Nobel chemistry laureate, estimated that water was especially abundant on Venus, with humidity six times the average on Earth. “We must therefore conclude that everything on Venus is dripping wet” — thereby accelerating the growth of vegetation, Arrhenius wrote.

But the early observations of Venus’ atmosphere were crude. About a century ago, refined techniques at the Mount Wilson Observatory in California contradicted the previous findings; oxygen and water vapor actually seemed scarce in the Venusian clouds. (In fact, as spacecraft visiting Venus in recent decades have shown, the air there is nearly all carbon dioxide with a little bit of nitrogen, plus only slight traces of water.) “It may be that the exacting conditions for the origin of life have not been satisfied” on Venus, Charles E. St. John and Seth B. Nicholson wrote in 1922 in the Astrophysical Journal.

Of course, it was possible that conditions on the surface, hidden by the thick clouds, might still allow life to find a way. 

“There is a possibility that the atmosphere of Venus is permeated with a finely divided dust, a possible product of intense volcanic activity, which would act as an excellent reflector of the sun’s rays and would at the same time effectually conceal the surface,” Isabel Lewis of the U.S. Naval Observatory wrote in Science News-Letter, the predecessor of Science News, in 1922. In 1926, the prominent astronomer Harlow Shapley maintained that in the solar system, Venus “more nearly fulfills the conditions (for life) than any planet other than the Earth…. But we cannot penetrate the dense covering of clouds and seek out the secrets of its surface.”

In 1927, Science News-Letter writer Frank Thone surveyed the prospects for life on other planets and declared Venus “the darling of the solar system” (excepting Earth, of course). While Mars seemed “wry and withered,” he wrote, “our sister Venus seems to have the vigor and sap of life in her.”

Yet as Thone acknowledged, the thick atmosphere guarding Venus’ surface from view made the question of life there unanswerable — probably, Thone guessed, for many generations.

And so today, the mystery remains unsolved. Phosphine sightings leave the question of whether Venus hosts life in a situation similar to that of Mars, long ago, when the newspaper publisher William Randolph Hearst (legend has it) cabled an astronomer asking for an article on the topic. “Is there life on Mars? Please cable one thousand words,” Hearst wrote. To which the astronomer cabled back: “Nobody knows. Repeat 500 times.”

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