Don't miss last week's most-read essay, on the potential for life on rogue planets that don't orbit stars: http://ow.ly/LLTzD
4:01 PM - 18 Apr 2015
0 replies
2 retweets
5 likes
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.