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Earth’s Gold Forged in Stellar Collisions

This artist's illustration shows two neutron stars at the moment of collision. New observations confirm that colliding neutron stars produce short gamma-ray bursts. Such collisions produce rare heavy elements, including gold. All Earth's gold likely came from colliding neutron stars. Credit: Dana Berry, SkyWorks Digital, Inc.

This artist’s illustration shows two neutron stars at the moment of collision. New observations confirm that colliding neutron stars produce short gamma-ray bursts. Such collisions produce rare heavy elements, including gold. All Earth’s gold likely came from colliding neutron stars.  Credit: Dana Berry, SkyWorks Digital, Inc.

Until today, astronomers believed that all the gold on Earth, and in the universe, was forged in ancient supernova explosions. But new evidence points to a far more violent birth for this most precious metal.

The new culprit is the cataclysmic collision of two neutron stars. The impact produces a titanic flash of intense but short-lived gamma ray bursts (GRB) along with a debris cloud filled with a complex cocktail of heavy elements, including copious amounts of gold. (Related Silver in Space: Metal Found to Form in Distinct Star Explosions)

Using NASA’s SWIFT gamma-ray hunting satellite, astronomers on June 3 detected just such a distant, high-energy explosion—dubbed GRB 130603B—some 3.9 billion light-years from Earth. The team of astronomers estimates that material (some of it gold) equal to about one-hundredth the mass of our sun, was ejected by the gamma-ray burst. (see also Ultrabright Gamma-ray Burst “Blinded” NASA Telescope)

Edo Berger, lead author of the new study and astrophysicist at the Harvard-Smithsonian Center for Astrophysics, and his team followed the resulting infrared glow from the burst for days until it faded out of sight. This glow can only be produced by the radioactive heavy elements rich in neutron stars, and the team believes it indicates that GRBs are a product of two neutron stars merging.

With several moons worth of gold being produced by just one GRB, and the many such blasts that are thought to have occurred  since the Big Bang nearly 14 billion years ago, Berger and his team suggest that neutron star collisions are the primary factories for gold in the cosmos.

“We estimate that the amount of gold produced and ejected during the merger of the two neutron stars may be as large as ten moon masses—quite a lot of bling!” said Berger in a press statement.

At today’s market rate, that amount of gold would be valued at ten octillion dollars—that’s a 1 with 28 zeros behind it, says Berger.

Unlike supernovae, where lighter elements like carbon and iron are born from the demise of a single star, GRBs are the universe’s most cataclysmic events and are powerful enough to forge precious metals.

“To paraphrase Carl Sagan, we are all star stuff, and our jewelry is colliding-star stuff,” said Berger.

The gold study has been submitted for publication in The Astrophysical Journal Letters and available online.

 

Follow Andrew Fazekas, the Night Sky Guy, on Twitter and Facebook.

 

 

Comments

  1. pia
    philippines
    July 20, 2013, 1:29 pm

    wow. that’s all i could ever say after i’ve read this article. WOW!

  2. David
    TX
    July 18, 2013, 6:27 pm

    If you were to drop an object onto a neutron star from a height of just 1 meter, it would impact the surface in about 1 microsecond, at about 7.2 million kph. If that object has a mass of 1kg, that impact will have the energy of around 500 tons of TNT. One milliliter of neutron star material has a mass of more than a billion metric tons.

    The properties of a single neutron star are already mind-bogglingly extreme. The violence of two of them colliding is just unimaginable

  3. blair
    United States
    July 18, 2013, 12:38 pm

    yes, let’s make it all about money

    and ignore the question of how two colliding balls of neutrons created protons in the first place

    because being thralls to the greed culture is more important than understanding how the universe works…

  4. Calgary Indians
    Canada
    July 18, 2013, 3:19 am

    yes, there was a strange glow in the space. This has given evidence that all the gold on Earth was forged by the historic collisions of dead stars.
    Despite being a long thought that gold was created in a stellar explosion called supernova. But that did not fully explain the exact amount of the gold in the solar system.

  5. Angelgroove
    Silicon Valley, CA
    July 17, 2013, 3:53 pm

    Time to build a rocket ship! How cool is this!