ngc672 2

NGC 672 is a spiral galaxy in the northern constellation of Triangulum, positioned around 2° to the southwest of the star Alpha Trianguli. The original object designated NGC 672 was discovered by the German-born astronomer William Herschel on 26 October 1786, but this was later cataloged as NGC 614. The object now identified as NGC 672 was discovered by John Herschel on 11 November 1827.

This galaxy is located at a distance of approximately 23.4 megalight-years from the Milky Way, where it forms an interacting pair with the irregular galaxy IC 1727. In the neutral hydrogen radio band, a tidal bridge is observed between the galaxies. NGC 672 appears to be the more massive of the two, and hence IC 1727 shows more distortion from the interaction. Together they form members of a combined group of galaxies that includes NGC 784.

The two galaxies NGC 672 and IC 1727 are physically very close and show gravitational interaction with one another. IC 1727 shows a strong asymmetry in the apparent distribution of young stars, while that of older stars is more even. The galaxy NGC 672 shows no asymmetry in the distribution of stars of different ages. The distance from NGC 672 is estimated at 7.22 ± 0.10 Mpc and that from IC 1727 at 7.14 ± 0.10 Mpc. It is estimated that star formation in the two galaxies occurred in two intervals 20-30 and 450-700 million years ago.

I will leave it as an excercise to the reader to identify the much more distant red shifted splinter galaxy, center left.