Using gravitational waves to catch runaway intergalactic black holes

4 July 2016 Astronomy Now

Researchers at the University of Cambridge have developed a new method for detecting and measuring one of the most powerful, and most mysterious, events in the universe — a black hole being kicked out of its host galaxy and into intergalactic space at speeds as high as 5,000 kilometres per second (11 million miles per hour).


No large caverns found inside Comet 67P

4 February 2016 Astronomy Now

Comets are known to be a mixture of dust and ice, and if fully compact, they would be heavier than water. However, measurements have shown some of them to have densities much lower than that of water ice, implying that comets must be highly porous. A new study of low-density Comet 67P/Churyumov-Gerasimenko using data from ESA’s Rosetta spacecraft rules out a cavernous interior.