This huge group of galaxies is the most massive structure within a billion light-years from us.
ESA & Planck Collaboration / Rosat/ Digitised Sky Survey
ESA's Planck mission recently took a look at the Shapley Supercluster in microwave light. The massive grouping has more than 8000 galaxies and a total mass of more than ten million billion times the mass of our sun.
Image: ESA & Planck Collaboration / Rosat/ Digitised Sky Survey
ESA & Planck Collaboration / Rosat/ Digitised Sky Survey