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Birthday · October 4, 2021

NGC 4676: When Mice Collide

October 4, 2021

Some stars end in silence, some in fire, and some leave behind the raw materials for birthdays.

NGC 4676: When Mice Collide

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APOD published October 4, 2021. 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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NGC 4676: When Mice Collide

Original APOD · October 4, 2021

These two mighty galaxies are pulling each other apart. Known as the "Mice" because they have such long tails, each spiral galaxy has likely already passed through the other. The long tails are created by the relative difference between gravitational pulls on the near and far parts of each galaxy. Because the distances are so large, the cosmic interaction takes place in slow motion -- over hundreds of millions of years. NGC 4676 lies about 300 million light-years away toward the constellation of Bernice's Hair (Coma Berenices) and are likely members of the Coma Cluster of Galaxies. The featured picture was taken with the Hubble Space Telescope's Advanced Camera for Surveys in 2002. These galactic mice will probably collide again and again over the next billion years so that, instead of continuing to pull each other apart, they coalesce to form a single galaxy. Follow APOD in English on: Facebook, Instagram, or Twitter

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