Credit: ESA/Hubble & & NASA, J. Dalcanton, Dark Energy Survey, DOE, FNAL, DECam, CTIO, NOIRLab/NSF/AURA, ESOAcknowledgement: J. Schmidt
The topic of this image is a group of 3 galaxies, collectively called NGC 7764A. They were imaged by the NASA/ESA Hubble Space Telescope, utilizing both its Advanced Camera for Surveys (ACS) and Wide Field Camera 3 (WFC3). The two galaxies in the upper right of the image seem interacting with one another– undoubtedly, the long tracks of stars and gas extending from them both offer the impression that they have actually both simply been struck at terrific speed, thrown into disarray by the bowling-ball-shaped galaxy to the lower left of the image.
In truth, however, interactions between galaxies take place over long time periods, and galaxies rarely clash head-on with one another. It is also uncertain whether the galaxy to the lower left is actually communicating with the other 2, although they are so reasonably close in space that it appears possible that they are. By pleased coincidence, the collective interaction in between these galaxies have caused the 2 on the upper right to form a shape, which from our Solar Systems perspective, resembles the starship understood as the USS Enterprise from Star Trek!
NGC 7764A, which lies about 425 million light years from Earth in the constellation Phoenix, is an interesting example of simply how awkward astronomical nomenclature can be. The three galaxies are separately described as NGC 7764A1, NGC 7764A2 and NGC 7764A3, and simply to be actually tough, a completely different galaxy, named NGC 7764, beings in the skies about a Moons distance (as seen from Earth) away. This rather haphazard calling makes more sense when we consider that a number of the catalogues for keeping track of heavenly bodies were put together well over 100 years earlier, long before modern innovation made standardizing scientific terminology much easier. As it is, numerous astronomical objects have a number of different names, or may have names that are so comparable to other items names that they trigger confusion.
