ABOUT THIS IMAGE:

This beautiful pair of interacting galaxies consists of NGC 5754, the large spiral on the right, and NGC 5752, the smaller companion in the bottom left corner of the image. NGC 5754's internal structure has hardly been disturbed by the interaction. The outer structure does exhibit tidal features, as does the symmetry of the inner spiral pattern and the kinked arms just beyond its inner ring. In contrast, NGC 5752 has undergone a starburst episode, with a rich population of massive and luminous star clusters clumping around the core and intertwined with intricate dust lanes. The contrasting reactions of the two galaxies to their interaction are due to their differing masses and sizes. NGC 5754 is located in the constellation Bootes, the Herdsman, some 200 million light-years away.

This image is part of a large collection of 59 images of merging galaxies taken by the Hubble Space Telescope and released on the occasion of its 18th anniversary on 24th April 2008.

Note:

These two interacting galaxies are only a part of Arp 297. Arp 297 is actually a quartet consisting of two separate interacting pairs, NGC 5754/NGC 5752 and NGC 5755/NGC 5753, in the same line of sight. Halton Arp's Atlas of Peculiar Galaxies was based on observations only. Subsequent measurements show that the NGC 5754/52 pair is about 200 million light-years away while the NGC 5752/54 pair are at about twice the distance.