Reefa Posted May 13, 2014 Share Posted May 13, 2014 Here on Earth, at NASA’s Ames Research Center in California, scientists have created stardust — or more accurately, they’ve recreated the dust that forms in the outer atmosphere of a dying red giant star (such a red giant is pictured above, with its dust cloud perfectly captured by Hubble). Out there in space, over millions of years, this interstellar dust gathers together into a nebula and goes on to coalesce into planets and other stars. Down here on Earth, of course, NASA isn’t trying to create its own planets (not yet, anyway) — no, they have the much more humble undertaking of trying to better understand how the universe and its trillions of planets and stars evolved over the last 14 billion years.At the Ames Research Center, NASA’s Cosmic Simulation Chamber (which is lumbered with the fantastically useless acronym COSmIC) has the exceedingly rare ability to recreate the harsh conditions of deep space. There, on the outer edge of a dying star, temperatures average 100 Kelvin (-170C, -273F), the atmosphere is one billionth that of Earth’s, and there’s tons of ultraviolet radiation. While the COSmIC mimics these conditions, the scientists inject some small hydrocarbon molecules, and then watch as various chemical processes turn these molecules into the solid dust grains that are produced en masse by dying stars.Real-life stardust, created by NASA’s COSmIC Once the experiment is completed, the dust is collected an analyzed with Ames’ scanning electron microscope (SEM), which produces the photos that you see here. The grains came in a variety of sizes, “on the order of 10 nm size, grains ranging from 100-500 nanometers and aggregates of grains up to 1.5 micrometers in diameter,” said Ames research fellow Ella Sciamma-O’Brien.While this might not sound all that exciting, there are significant implications and ramifications for both planetary science and astrophysics. Until now, we really had no idea what kind of dust formed around stars — we know that that large clouds of cosmic dust can eventually become a nebula, which then coalesces into new stars and planet, but beyond that we have to do a lot of guesswork about the exact details of the star- and planet-forming process. Until we fly a probe out to the nearest star-forming nebula (which is probably the Orion Nebula at 1350 light years distant), making interstellar dust here on Earth is the next best thing. Obviously, the more we know about how the universe’s evolution, the more we can know about our place in it. This story also has increased significance — for me, at least — because the new version ofCosmos is currently being aired on TV. Cosmos was originally written by Carl Sagan, who was very fond of saying that everything in the world — everyone you have ever known or loved, everything you’ve eaten, everywhere you’ve been — is made of star stuff. Here he was referring to the fact that everything stems from the repeated births and deaths of stars, where the process of nuclear fusion creates the elements that make rocks, life, and apple pies possible. And now, for the very first time, we’ve made our very own star stuff here on Earth.Source Quote Link to comment Share on other sites More sharing options...
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