[4] This galaxy's slightly distorted wedge shape gives it the appearance of a herring or a whale, hence its nickname.

NGC 4631 contains a central starburst, which is a region of intense star formation.

So many supernovae have exploded in the center of NGC 4631 that they are blowing gas out of the plane of the galaxy.

[8] Although no supernovae have been observed in NGC 4631 yet, a luminous red nova, designated AT 2021biy, was discovered on 29 January 2021 (type LRN, mag.

[11][12][13][14] However, exact group identification is problematic because this galaxy and others lie in a part of the sky that is relatively crowded.