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Birthday · July 22, 2015

Gamma-ray Rain from 3C 279

July 22, 2015

Even the most precise clock in the world cannot measure how unlikely your existence really is.

Gamma-ray Rain from 3C 279

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APOD published July 22, 2015 · Video still. Full image credits are on the original APOD entry below. A publication-date match, not a photo taken on your date. Independent of NASA.

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Gamma-ray Rain from 3C 279

Original APOD · July 22, 2015

If gamma-rays were raindrops a flare from a supermassive black hole might look like this. Not so gently falling on the Fermi Gamma-ray Space Telescope from June 14 to June 16 the gamma-ray photons, with energies up to 50 billion electron volts, originated in active galaxy 3C 279 some 5 billion light-years away. Each gamma-ray "drop" is an expanding circle in the timelapse visualization, the color and maximum size determined by the gamma-ray's measured energy. Starting with a background drizzle, the sudden downpour that then trails off is the intense, high energy flare. The creative and calming presentation of the historically bright flare covers a 5 degree wide region of the gamma-ray sky centered on 3C 279.

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