This movie shows pulsed gamma rays from the Vela pulsar as constructed from photons detected by Fermi's Large Area Telescope. The Vela pulsar, located in our galaxy several hundred light years away from Earth, spins 11 times a second and is the brightest persistent source of gamma rays in the sky. The movie includes data from August 4 to Sept. 15, 2008. The bluer color in the latter part of the pulse indicates the presence of gamma rays with energies exceeding a billion electron volts (1 GeV). For comparison, visible light has energies between two and three electron volts. Red indicates gamma rays with energies less than 300 million electron volts (MeV); green, gamma rays between 300 MeV and 1 GeV; and blue shows gamma rays greater than 1 GeV. The movie frame is 30 degrees across. The background, which shows diffuse gamma-ray emission from the Milky Way, is about 15 times brighter here than it actually is.

Credit: NASA/DOE/Fermi LAT Collaboration

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