Inseparable Galactic Twins | NASA

Hubble image of galaxy pair MRK 1034
Image Credit : ESA/Hubble and NASA (acknowledgement, Judy Schmidt)

Looking towards the constellation of Triangulum (The Triangle), in the northern sky, lies the galaxy pair MRK 1034. The two very similar galaxies, named PGC 9074 and PGC 9071, are close enough to one another to be bound together by gravity, although no gravitational disturbance can yet be seen in the image. These objects are probably only just beginning to interact gravitationally.

Both are spiral galaxies, and are presented to our eyes face-on, so we are able to appreciate their distinctive shapes. On the left of the image, spiral galaxy PGC 9074 shows a bright bulge and two spiral arms tightly wound around the nucleus, features which have led scientists to classify it as a type Sa galaxy. Close by, PGC 9071 — a type Sb galaxy — although very similar and almost the same size as its neighbor, has a fainter bulge and a slightly different structure to its arms: their coils are further apart.

via Inseparable Galactic Twins | NASA.