Wednesday, July 17, 2013

Beauty for ashes; [Isa. 61:3]

Origin of gold found in rare neutron-star collisions

Fairbanks Gold Mining Inc./AP - Fort Knox Mine, which is currently the largest operating gold mine in Alaska. A new study based on observations from space suggests the gold on Earth came from rare neutron-star collisions.

By Joel Achenbach, Updated: Wednesday, July 17, 3:51 PM E-mail the writer

Gold — atomic number 79, element symbol Au, the most widely beloved of the precious metals — might have its origin in extremely rare and violent explosions in the far reaches of outer space. The bling apparently begins with a blam.
For many years, scientists had theorized that the heavy elements of the periodic table, such as gold, platinum, lead and uranium, had their origin in supernova explosions. But an astronomical observation in June has produced evidence that such metals come from something even more exotic: the collisions of ultra-dense objects called neutron stars.

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The birthplace of gold

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The year in space: In 2013, scientists captured stunning images of the planets, a galaxy, a planetary nebula and more from space.

It has long been understood that Earth’s elements are of cosmic origin. Carbon and oxygen atoms in our bodies, for example, come from the interior of stars, where they were formed under high pressure and heat. They were later spewed into the universe in supernova explosions. It is literally true, as the late astronomer Carl Sagan was fond of saying, that we are all star stuff.
But new evidence suggests that gold and other heavy elements don’t come from supernovas, but from the neutron-star smashups.
“We are all star stuff, and our jewelry is colliding-star stuff,” said Edo Berger, an astronomer who led the research at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.
Neutron stars are the collapsed cores of stars that have exploded in a supernova. A neutron star might be roughly the diameter of the District but contain as much mass as our sun, or more, with all of it crammed together by the force of gravity until even the atoms have collapsed, leaving the object with the density of an atomic nucleus