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[slate]

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[slate]

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So first part of this

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discovery comes from the LIGO observatory which for the first

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time detected gravitational waves, ripples in space-time

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from two colliding neutron stars

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And if that wasn't enough just two seconds later

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with the Fermi Gamma Ray space Telescope we detected

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a short bright flash of high energy light that we call a gamma ray

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burst. This alerted the entire astronomical community

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to the fact that something very exciting was happening and over

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70 telescopes from around the world. searched for a counterpart

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in other wavelengths. They were able to identify the host galaxy and

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study the remains of this explosion in amazing details.

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[slate]

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That's exactly what I'm saying. For the first time we could actually

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weigh the amount of heavy metals that were formed in one of these

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systems. Over two hundred times the weight of the Earth.

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was formed in gold and platinum following the merger of these

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systems. They were thrown out at very high speeds and dispersed throughout

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the universe and eventually they were formed as

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stars and planets like Earth.

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[slate] So Fermi and other

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NASA satellites quite often detect what we call gamma ray bursts, very

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short high energy flashes. Gamma ray

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radiation. Several dozen times a year at least. What

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makes this really amazing is that you're actually able to see

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the source that powered this gamma ray emission

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from gravitational waves. We could link the merger of two

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neutron stars to the gamma ray burst which is something

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we hypothesized was the case for a long time

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but now we had really direct confirmation that that was happening. That's the first time

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we've been able to do that.

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[slate] Gravitational waves are often referred to

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as ripples in space-time when a very dense

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massive object accelerates, it actually causes gravitational

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energy to propagate throughout the universe, changing the distance

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between sources that are relatively close to each other. And

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with very precise detectors on the ground we can actually measure

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those changes and use them to infer the presence of these really remarkable

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collisions.