NGC 2207 and 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. NGC 2207 was discovered by British astronomer John Herschel on 24 January 1835, while IC 2163 was discovered by Herbert Howe on 11 February 1898. The pair together carry the nickname the Cosmic Owl.
The larger spiral, NGC 2207, is classified as an intermediate spiral galaxy exhibiting a weak inner ring structure around the central bar. The smaller companion spiral, IC 2163, is classified as a barred spiral galaxy that also exhibits a weak inner ring and an elongated spiral arm that is likely being stretched by tidal forces with the larger companion. Both galaxies contain a vast amount of dust and gas, and are beginning to exhibit enhanced rates of star formation, as seen in infrared images.
NGC 2207 is in the process of colliding and merging with IC 2163. But unlike the Antennae or the Mice Galaxies, they are still two separate spiral galaxies. They are only in the first step of colliding and merging, with NGC 2207 being in the process of tidally stripping IC 2163. Soon they will collide, probably looking a bit more like the Mice Galaxies. In about a billion years' time they are expected to merge and become an elliptical galaxy or perhaps a disk galaxy.
Supernovae
Five supernovae have been observed in NGC 2207:- SN 1975A was discovered by Justus R. Dunlap on 15 January 1975.
- SN 1999ec was discovered by the Lick Observatory Supernova Search on 2 October 1999.
- SN 2003H was discovered by LOTOSS on 8 January 2003, located halfway between the two galaxies.
- SN 2013ai was discovered by E. Conseil on 1 March 2013.
- AT 2019eez was discovered by ASAS-SN on 27 April 2019.
- SN 2018lab was discovered by the Distance Less Than 40 Mpc Survey on 29 December 2018.
- SN 2010jp was discovered by The CHilean Automatic Supernova sEarch on 11 November 2010.