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.
Water is a hot topic in the study of exoplanets, including “hot Jupiters” close to their parent stars that can reach a scorching 1,100 °C, meaning any water they host would take the form of vapour. Hot Jupiters have been found with water in their atmospheres, but others appear to have none. NASA scientists wanted to find out what the atmospheres of these giant worlds have in common.
When our galaxy was born, around 13,000 million years ago, a plethora of clusters containing millions of stars emerged. But over time, they have been disappearing. However, hidden behind younger stars that formed later, some old and dying star clusters remain, such as the so-called E 3. European astronomers have now studied this testimony to the beginnings of our galaxy.
Astronomers have discovered evidence for an unusual kind of black hole born extremely early in the universe. They showed that a recently discovered unusual source of intense radiation is likely powered by a “direct-collapse black hole,” a type of object predicted by theorists more than a decade ago.