Credit: SunyaevZeldovich effect: ESA Planck Collaboration; optical image: STScI Digitized Sky Survey

Planck has discovered a bridge of hot gas that connects galaxy clusters Abell 399 (lower center) and Abell 401 (top left). The galaxy pair is located about a billion light-years from Earth, and the gas bridge extends approximately 10 million light-years between them.

The image shows the two galaxy clusters as seen at optical wavelengths with ground-based telescopes and through the Sunyaev-Zel'dovich effect (in orange) with the Planck satellite.

Provider: Planck

Image Source: http://planck.ipac.caltech.edu/image/planck12-003a

Curator: NASA Planck Science Center, Pasadena, CA, USA

Image Use Policy: Public Domain