NGC 6872 and IC 4970 are two galaxies in the process of undergoing a collision. IC 4970 is the small galaxy at the top of the image that, thanks to Chandra and Spitzer data. New images show IC 4970 has stripped cold gas from NGC 6872 and is using it to feed its growing supermassive black hole. The galaxies and black holes co-exist, inextricably linked in their evolution. To better understand this symbiotic relationship, scientists have turned to rapidly growing black holes – so-called active galactic nucleus (AGN) – to study how they are affected by their galactic environments. The latest data from Chandra and Spitzer show that IC 4970, the small galaxy at the top of the image, contains an AGN, but one that is heavily cocooned in gas and dust. This means in optical light telescopes, like the VLT, there is little to see. X-rays and infrared light , however, can penetrate this veil of material and reveal the light show that is generated as material heats up before falling onto the black hole (seen as a bright point-like source).

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Image of the Day: The Tango of Galaxies in Collision