Lab notes: neutron stars collide; sexism and syphilis – the week in science

A new frontier for science opened on Monday, when astronomers around the world witnessed neutron stars colliding - and resolved the debate about where gold and platinum come from. The extraordinary event, first picked up by the US-based observatory Ligo, in which the two ultra-dense stars spiralled inwards, violently collided and probably collapsed into a black hole, was "seen" for the first time, in both gravitational waves and light. In another first, Japan's space agency Jaxa announced that its Selene probe had come across a 54km-long chasm beneath the lunar surface that could be turned into an exploration base for astronauts. In a breakthrough for artificial intelligence, Google DeepMind has unveiled AlphaGo Zero, which took just three days to master the ancient Chinese board game of Go. Representing a leap from its 2015 predecessor, the program can learn without human input, and is a milestone on the road to general-purpose AIs working in medicine and science. Researchers explained the ability of whales and dolphins to learn, play and use tools applying the "cultural brain hypothesis" normally applied to humans. They argued cetaceans' intelligence developed, and their brains grew, as a way of coping with large and complex social groups. The acoustic design of theatres in Ancient Greece evolved to meet the cultural needs of a large group to hear the performance on stage. A study has made approximately 2,400 recordings at three sites, including the ancient theatre of Epidaurus, and concluded that the theatres' famed ability to convey a stage whisper to the cheap seats is a myth.