When galaxies get close enough to each other, tidal forces can tug entire star systems out of place, distorting the shapes of the interacting pair in sometimes dramatic fashion. When galaxies with active galactic nuclei interact, the result can be spectacular, as in this Hubble Space Telescope view of Arp 282, made up of Seyfert galaxy NGC 169 (bottom) and IC 1559 (top). Hidden in the cores of both galaxies are supermassive black holes, actively feasting on surrounding stars, gas and dust. Delicate streams of matter can be seen visibly connecting the two galaxies in a dramatic, 3D-like demonstration of titanic tidal interactions.
While NGC 278 may look serene, it is anything but. The galaxy is currently undergoing an immense burst of star formation as revealed in this NASA/ESA Hubble Space Telescope image. However, NGC 278’s star formation is somewhat unusual: why is it only taking place within an inner ring some 6,500 light-years across and not extend to the galaxy’s outer edges?
Astronomers at Swinburne University of Technology, Melbourne, have discovered an unusually shaped structure in two nearby disc galaxies. The Swinburne team recently developed new imaging software, making it possible to observe the double “peanut shell shape” formed by the distribution of stars bulging from the centres of these galaxies.