A long time ago in a galaxy far, far away


A chara, – You report that, “A collision of two neutron stars, 130 million light years away, has opened up a new window on the universe. The spectacular event occurred on August 17th” (Space – a new frontier is announced” , October 16th). It did not occur on August 17th. It happened in NGC 4993, a (relatively) nearby elliptical galaxy, which is indeed 130 million light years away. But that means that it happened 130 million years ago; it has taken that time for the news to get here. Perhaps another spectacular aspect of the episode is that it has been observed here at all! – Is mise,



Dublin 16.