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Music

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Music

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Announcer: Five, four, three,

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engines start, one, zero, and

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liftoff of the Delta rocket carrying GLAST, a

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gamma-ray telescope searching for unseen physics in the stars of the

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galaxies. Narrator: Launched on June 11, 2008,

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GLAST, renamed the Fermi Gamma-ray Space Telescope, has

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been collecting gamma-ray data for five years. In that time

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it has made some astounding observations of some of the most powerful events

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and objects in the universe. Including some right on our doorstep.

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Narrator 2: Fermi looks at gamma rays, the highest energy form of light,

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and it just surprised everyone with a discovery about the fabric of space and time.

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Julie McEnery: Because Fermi saw no delay in the arrival time of the two photons, it

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confirms that space and time is smooth and continuous as

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Einstein had predicted. Narrator 3: With Fermi,

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astronomers have made the most accurate measurement of starlight in the universe, and

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used it to establish the total amount of light from all the stars that have ever shown.

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Narrator 4: In April 2013,

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a shockingly bright blast of gamma rays from a dying in a

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distant galaxy, produced the highest-energy light ever detected from such an event.

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Elizabeth Hays: Every three hours

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the Large Area Telescope on board Fermi builds up a picture of the sky in

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gamma rays. One thing it sees a lot of is blazars--active galaxies

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whose emissions are powered by supermassive black holes. Because we're

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watching them all the time, we can track their activity and alert other telescopes to

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new flare-ups. Narrator 5: Two years of scanning the sky with Fermi's

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Large Area Telescope have set the strongest limits yet for WIMP

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dark matter. The longer Fermi operates, the better its ability either

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to box in the nature of dark matter, or to find actual evidence of what it is.

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Narrator 6: Scientists have recently discovered a gigantic,

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mysterious structure in our galaxy. This never-before-seen feature looks like

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a pair of bubbles extending above and below our galaxy's center.

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Narrator 7: New images show where supernova remnants

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emit gamma rays a billion times more energetic than visible light.

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This glow suggests that the remnants are a source of cosmic rays--

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protons and electrons accelerated to near light speed.

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Narrator 8: Observations of two supernova remnants by NASA's Fermi Gamma-ray

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Space Telescope conclusively show these supernova remnants are accelerating

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protons. When they strike protons in nearby molecular clouds,

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they produce the gamma-ray emission Fermi sees.

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Narrator 9: Recently, astronomers have observed incredible flares in the nebula that theorists are hard-pressed

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to explain. The gamma rays most likely arise from electrons moving near the speed of

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light, but to account for these flares, the electrons must have the highest energies

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ever seen in cosmic sources. Narrator 10: In three

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years Fermi has detected more than 100 gamma-ray pulsars. And about a third of gamma-ray

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pulsars were discovered by Fermi on the basis of their gamma-ray pulsations alone.

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Narrator 11: In late 2010, NASA's Fermi Gamma-ray Space

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Telescope watched the system glow with faint gamma emission as the pulsar first

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approached the disk. Astronomers expected the same behavior in early 2011

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when the outbound pulsar grazed the disk again, but, instead,

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Fermi detected intense and puzzling gamma-ray flares.

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Roger Romani: We managed to get enough observations of the object to piece together its orbital period.

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And found, remarkably, that it was an incredibly heated

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object--blue white on one side, deep, deep red on the other--

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and it was orbiting around an energetic pulsar with an orbital period of about one-and-a-half

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hours. The gamma rays are blasting the companion at point-blank range.

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Narrator 12: Fermi found that star birth and

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death in the Cygnus X star factory corrals particles and

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boosts them to cosmic-ray energies. Narrator 13: In

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early March 2012, a powerful flare erupted on the sun

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During this event, the LAT detected the highest energy light every recorded from a

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solar flare. Narrator 14: New observations by NASA's Fermi

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Gamma-ray Space Telescope show that thunderstorms make antimatter.

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The process starts with a terrestrial gamma-ray flash, or TGF;

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an intense pulse of gamma rays originating from thunderstorms.

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Narrator 15: Scientists have discovered that radio signals, once thought to be produced by the lighting

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that triggers a TGF, are in fact broadcast by TGFs themselves.

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Eric Stoneking: There was a defunct Russian satellite

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in an orbit that would intersect Fermi's orbit in about a week. Julie McEnery: Those two spacecraft

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were occupying the same space within 30 milliseconds of each other.

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That's why this was scary. Having done the maneuver, and avoided

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a collision means we continue operating, so continue doing

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the great science that we have been doing over the past four-and-a-half years.

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Music

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Beeping

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Beeping