Tuesday, July 23, 2013

Scientists Believe Gold and Platinum Are Forged in the Explosive Aftermath of Neutron Star Collisions

Harvard scientists believe that all the Earth’s gold and platinum can be traced to one of the most violent explosions in the universe — a gamma-ray burst produced in the collision of two neutron stars.

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Their findings finally unravel a long-standing mystery of how rare precious metals and other “heavy” elements found their way to our planet.

The late astronomer and Pulitzer Prize-winning author Carl Sagan famously said that we are all made of “starstuff,” meaning that dying stars billions of years ago cooked up the lighter, basic elements on the planet.

“The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff,” Sagan wrote in Cosmos.

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But scientists had remained baffled about the origins of the heaviest elements, including gold and platinum (79 and 78, respectively, on the Periodic Table).

Then the answer emerged last month...

On June 3, NASA’s Swift satellite observed a gamma-ray burst 3.9 billion light-years away that astrophysicists believe was the result of a clash of neutron stars.

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Images of the burst captured by the Hubble Telescope nine days later showed evidence that the collision generated a bevy of heavy elements, including the equivalent of several moon masses of gold, according to Edo Berger of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.

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"Call it the golden glow," Berger told USA Today. "In this case, we were able to observe it for the first time and see how the merger seems to be producing the heavy elements."

While common stars collide in our galaxy about once every century, explosive collisions of neutron stars occur once in 10,000 years.

Neutron stars weigh more than our sun, but are barely the size of Manhattan. When these already-dense masses collide, they have the ability to generate gold and other heavy elements.

So, if these neutron star collisions produced several moon masses of gold, how much would that be worth?

"At today's prices, that amount of gold would be worth 10 octillion dollars," Berger told USA Today.

Star illustrations: NASA

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