Proto-Cluster Candidates (IMAGE) University of Arizona Caption The Planck all-sky map at submillimeter wavelengths (545 GHz). The band running through the middle corresponds to dust in our Milky Way galaxy. The black dots indicate the location of the proto-cluster candidates identified by Planck and subsequently observed by Herschel. The inset images showcase some of the observations made by Herschel's SPIRE instrument; the contours represent the density of galaxies. Credit ESA and the Planck Collaboration/ H. Dole, D. Guéry & G. Hurier, IAS/University Paris-Sud/CNRS/CNES Usage Restrictions This visual may only be used in conjunction with reporting on or posting of this news release. Credit must be given as indicated. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.