Hosts: Ed Brown, Penny Dumsday, Lucas Randall

00:02:00 There's a stream of stars hurtling through our region of the Milky Way galaxy, and they're bringing with them a "dark matter hurricane". It's probably nothing to worry about, though.

00:12:16 For the first time since 1889, the kilogram has been redefined according to a natural constant, instead of a lump of metal in a vault in Paris. The actual mass, for all intents and purposes, remains the same.

00:23:51 Previous studies of Neanderthal skulls found high rates of head injuries leading experts to believe they were a violent, savage people. But a new study finds that our human ancestors had a similar injuries and might not have been much different.

This episode contains traces of Professor Brian Greene explaining Dark Matter to CNN's Fareed Zakaria.