Best of 2010: The Death of Nemesis: The Sun’s Distant, Dark Companion
In July, scientists said the data that once suggested the Sun is orbited by a distant dark companion now raises even more questions
Over the last 500 million years or so, life on Earth has been threatened on many occasions; the fossil record is littered with extinction events. What’s curious about these events is that they seem to occur with alarming regularity.
The periodicity is a matter of some controversy among paleobiologists but there is a growing consensus that something of enormous destructive power happens every 26 or 27 million years. The question is what?