The active galaxy Hercules A was given that name because it is the brightest radio source in the constellation of Hercules. Astronomers found that the double-peaked radio emission corresponded to a giant elliptical galaxy cataloged as 3C 348. Unusually, this behemoth galaxy is not found within a large cluster of hundreds of galaxies, but rather within a comparatively small group of dozens of galaxies. The 'active' part of the galaxy is the supermassive black hole in its core, which spews out strong jets of energetic particles that produce enormous lobes of radio emission. Some astronomers suspect that Hercules A may be the result of two galaxies merging together.
This video envisions a three-dimensional look at the combined visible light (Hubble Space Telescope) and radio emission (Very Large Array) from Hercules A. The size of these radio lobes dwarfs the large galaxy and extends throughout the volume of the galaxy group. This visualization is intended only to be a scientifically reasonable illustration of the three-dimensional structures. In particular, the galaxy distances within the group are based on a statistical model, and not measured values.
Z. Levay, F. Summers, G. Bacon, T. Davis, and L. Frattare (STScI)
Production: November 29, 2012
Publication: February 23, 2014