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Gold formed by colliding neutron stars

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http://phys.org/news/2013-07-earth-gold-colliding-dead-stars.html

Earth's gold came from colliding dead stars

We value gold for many reasons: its beauty, its usefulness as jewelry, and its rarity. Gold is rare on Earth in part because it's also rare in the universe. Unlike elements like carbon or iron, it cannot be created within a star. Instead, it must be born in a more cataclysmic event - like one that occurred last month known as a short gamma-ray burst (GRB).

Observations of this GRB provide evidence that it resulted from the collision of two neutron stars - the dead cores of stars that previously exploded as supernovae. Moreover, a unique glow that persisted for days at the GRB location potentially signifies the creation of substantial amounts of heavy elements - including gold.

"We estimate that the amount of gold produced and ejected during the merger of the two neutron stars may be as large as 10 moon masses - quite a lot of bling!" says lead author Edo Berger of the Harvard-Smithsonian Center for Astrophysics (CfA).

Berger presented the finding today in a press conference at the CfA in Cambridge, Mass.

A gamma-ray burst is a flash of high-energy light (gamma rays) from an extremely energetic explosion. Most are found in the distant universe. Berger and his colleagues studied GRB 130603B which, at a distance of 3.9 billion light-years from Earth, is one of the nearest bursts seen to date.

Gamma-ray bursts come in two varieties - long and short - depending on how long the flash of gamma rays lasts. GRB 130603B, detected by NASA's Swift satellite on June 3rd, lasted for less than two-tenths of a second.

Although the gamma rays disappeared quickly, GRB 130603B also displayed a slowly fading glow dominated by infrared light. Its brightness and behavior didn't match a typical "afterglow," which is created when a high-speed jet of particles slams into the surrounding environment.

Instead, the glow behaved like it came from exotic radioactive elements. The neutron-rich material ejected by colliding neutron stars can generate such elements, which then undergo radioactive decay, emitting a glow that's dominated by infrared light - exactly what the team observed.

"We've been looking for a 'smoking gun' to link a short gamma-ray burst with a neutron star collision. The radioactive glow from GRB 130603B may be that smoking gun," explains Wen-fai Fong, a graduate student at the CfA and a co-author of the paper.

The team calculates that about one-hundredth of a solar mass of material was ejected by the gamma-ray burst, some of which was gold. By combining the estimated gold produced by a single short GRB with the number of such explosions that have occurred over the age of the universe, all the gold in the cosmos might have come from gamma-ray bursts.

"To paraphrase Carl Sagan, we are all star stuff, and our jewelry is colliding-star stuff," says Berger.

Provided by Harvard-Smithsonian Center for Astrophysics

earthsgoldca.jpg

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Should probably stop hording gold then...back to barrels o'oil I go...lets see you recreate that in lab

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Should probably stop hording gold then...back to barrels o'oil I go...lets see you recreate that in lab

Already been done using gen-modded algae & bacteria acting on biomass.

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I would really love for the world to find a vast deposit of gold, i know this would the value out, but gold being one of the best conductors of electricity would lead to a revolution in computing and electronics, devices requiring less power, more efficient. 

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Gold can also be created by the ancient Alchemy -- a lost art.

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Can you just imagine two neutron stars colliding, such cool stuff.

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This kind of stuff always amazes me. I love astronomy.

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Can you just imagine two neutron stars colliding, such cool stuff.

 

I can, I've thought about that sort of thing before. Along with a white dwarf syphoning gas off another star, and causing a helium flash on the surface of the white dwarf. Or even a carbon flash. But only in heavier carbon/oxygen remnant white dwarfs. I studied astrophysics in college, so I kinda love astronomy and quantum mechanics etc. Don't even get me started on supernova and pair-instability conversations :D

 

The universe is amazing. It is really sad most people can't see it that way, or don't want to see it that way.

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I can, I've thought about that sort of thing before. Along with a white dwarf syphoning gas off another star, and causing a helium flash on the surface of the white dwarf. Or even a carbon flash. But only in heavier carbon/oxygen remnant white dwarfs. I studied astrophysics in college, so I kinda love astronomy and quantum mechanics etc. Don't even get me started on supernova and pair-instability conversations :D

 

The universe is amazing. It is really sad most people can't see it that way, or don't want to see it that way.

I wish I even had a clue what half of that meant. I'm fascinated by astronomy, but not educated in it.

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What about silver?

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I wish I even had a clue what half of that meant. I'm fascinated by astronomy, but not educated in it.

 

You don't have to be educated in astronomy to appreciate it. Like you already do :)

 

What about silver?

 

If I remember correctly, silver is made specifically in supernova explosions. Along with us. Earth. Sun. Stuff.

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So if it is 3.9 billion light years away, does that mean that this explosion actually happened at least 3.9 billion years ago, and we're just now seeing it because of how long it took the light to get here?

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So if it is 3.9 billion light years away, does that mean that this explosion actually happened at least 3.9 billion years ago, and we're just now seeing it because of how long it took the light to get here?

 

Yes.

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If I remember correctly, silver is made specifically in supernova explosions. Along with us. Earth. Sun. Stuff.

IIRC normal stellar nuclear processes only produce elements up iron (mass 54-60) and nickel (mass 58-64). Heavier elements require more energetic processes like supernovae, collisions, etc. Silver is mass 105-111.

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So if it is 3.9 billion light years away, does that mean that this explosion actually happened at least 3.9 billion years ago, and we're just now seeing it because of how long it took the light to get here?

 

Until Nokia develops a camera that can see light before we can.

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Indeed. Iron is the end state of nuclear fusion in stars since after Iron-56, energy is consumed. Depending on the mass of the star, any number of things can happen at this point. Complete core collapse into a neutron star or black hole. Or a pair-instability event may happen where the resultant explosion is more powerful than the gravity binding everything together - leaving nothing behind. Not even a black hole. (Note, these are exceeding rare events in the universe, at least with our current understanding of it)

 

So yup, everything beyond Iron itself, is made in the supernova explosion itself, or in the core of the star before the explosion (and then spewed into space in the explosion).

 

Man I love this stuff.

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Gold can also be created by the ancient Alchemy -- a lost art.

 

 

I liked that episode of Fairy Tale Theater too.   :whistle:

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