NGC 4839

NGC 4839 is located near the edge of the Coma galaxy cluster, one of the largest known clusters in the universe about 340 million light-years away. As NGC 4839 moves toward the center of the Coma cluster, the hot gas in the galaxy group is stripped away by its collision with gas in the cluster. This results in a tail forming behind the galaxy group.

The image on the left shows an X-ray view of the Coma galaxy cluster taken with ESA’s (European Space Agency’s) XMM-Newton (blue), along with optical data from the Sloan Digital Sky Survey (yellow). The galaxy group NGC 4839 is located in the lower right of that image. The inset on the right is the Chandra image (purple) of the region outlined by the square. The head of NGC 4839’s tail is on the left side of the Chandra image and contains the brightest galaxy in the group and the densest gas. The tail trails to the right. (The Chandra image has been rotated so that north is about 30 degrees to the left of vertical.)

X-rays from the hot gas in the outer regions of the Coma cluster — that NGC 4839 is traveling through — are too faint to be seen in the XMM image shown here, but are highlighted in a supplementary, XMM-only image. This mosaic of images shows gaps between individual images where data was not obtained, and dark holes where point sources of X-rays were removed. ... https://www.youtube.com/watch?v=acsUyRDaT7I