The globular cluster M13 in Hercules is a favorite target for amateur astronomers and professionals alike, a vast concentration of stars easily visible in binoculars and even to the unaided eye on clear, dark nights. But through a telescope, M13 turns into a glimmering metropolis of more than 100,000 suns, one of the brightest and best-known globular clusters in the northern sky. Now rising in the early evening sky for viewers in the northern hemisphere, M13 offers an especially beautiful sight when imaged by the Hubble Space Telescope. This view is a composite of archival data collected in 1999, 2000, 2005 and 2006 with the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys.
The Hubble Space Telescope imaged a distant cluster of galaxies that was found by ESA’s Planck satellite, which detected distortions in the cosmic background radiation caused by the cluster’s gravity. Some five billion light years from Earth, the cluster’s members appear as a swarm of red-shifted galaxies, along with an arc of bluish light caused by gravitational lensing.
Researchers have found a large population of distant dwarf galaxies that could reveal important details about a productive period of star formation in the universe billions of years ago. It is believed that dwarf galaxies played a significant role during the so-called reionisation era in transforming the dark early universe into one that is bright, ionised and transparent.
A near-record 17-billion-solar-mass black hole discovered in a sparse area of the local universe indicates that these monster objects may be more common than once thought. The newly discovered supermassive black hole is in NGC 1600, an elliptical galaxy in the constellation Eridanus some 149 million light-years away.