Chandra Release - May 30, 2014

Visual Description: Elliptical Galaxies

These X-ray images showcase four of a sample of giant elliptical galaxies, which are characterized by their distinct shapes and colors. From top, left to right and bottom left to right is shown NGC 1399, NGC 4472, NGC 4636, and NGC 5044. Each of the images is colored in a rich sky blue, and resembles a large but irregularly shaped blue topaz gemstone glittering against a dark backdrop with bits of topaz dust sparkling around it.   The first image in the series, NGC 1399, displays a bright blue circular galaxy with white spots around it. This galaxy has a round shape, which is typical of elliptical galaxies.  The second image, NGC 4472, shows an even bigger and brighter blue circular galaxy, also with white spots around it. This galaxy shares similarities with the first one in terms of its round shape and presence of white spots.   The third image, NGC 4636, depicts an elliptical galaxy with two sets of what looks like interlocking arms.   The fourth image, NGC 5044, presents another irregularly shaped object, almost like a dense spider's web.   Chandra and the Hershel Space Observatory (not shown in the images) investigated these objects to understand why these galaxies have such low levels of star formation. Astronomers used Chandra to determine the role that supermassive black holes play in this dearth of stellar birth.  Outbursts from the supermassive black hole may be preventing the gas from cooling enough to allow stars to form.