Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2017 October 15
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On the Origin of Gold
Illustration Credit: Dana Berry, NASA

Explanation: Where did the gold in your jewelry originate? No one is completely sure. The relative average abundance in our Solar System appears higher than can be made in the early universe, in stars, and even in typical supernova explosions. Some astronomers have suggested, and many believe, that neutron-rich heavy elements such as gold might be most easily made in rare neutron-rich explosions such as the collision of neutron stars. Pictured here is an artist's illustration depicting two neutron stars spiraling in toward each other, just before they collide. Since neutron star collisions are also suggested as the origin of short duration gamma-ray bursts, it is possible that you already own a souvenir from one of the most powerful explosions in the universe.

Editorial Note: This "best of" APOD ran previously on 2011 September 11.
News Note: The next APOD will debut during an NSF discovery announcement and press briefing on Monday.
Tomorrow's picture: smashing discovery


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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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