NGC 2207 / IC 2163
NGC 2207 and IC 2163 are a pair of colliding spiral galaxies, about 80 million light-years away, in the constellation Canis Major. They are only in the first step of colliding and merging, and are still two separate spiral galaxies.
Both galaxies were discovered by John Herschel in 1835. So far three supernovae have been observed in NGC 2207.
NGC 2207 is in the process of tidal stripping IC 2163. In about a billion years time they will totally merge and become an elliptical galaxy.
The composition NGC 2207 / IC 2163 itself is a representation of various aspects of this colliding and merging, via cello and piano inter-reactions, compressed into just a few minutes time.
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