The Hubble Space Telescope captured this image of a gamma ray explosion [shown at two different scales] on January 23, 1999. At the time it was the most powerful explosion ever recorded.

According to NASA, gammaray bursts "may represent the most powerful explosions in the universe since the Big Bang, the explosive birth of our universe. Hubble images showed that these brief flashes of radiation come from far-flung galaxies that are forming stars at enormously high rates. By pinpointing the host galaxies, Hubble also identified the sources of the 'bursts': the collapse of massive stars."

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