Celestial Surprise: 5 Most Incredible Discoveries of the Week

A big astronomical claim and a century-old U-boat were among the discoveries making headlines:

• There May Be a 9th Planet Past Pluto: Pluto remains a lowly dwarf planet, but there's another icy orb even further out in our solar system that may be deemed a planet instead. The so-called "Planet Nine," thought to be five to 10 times as massive as Earth, is believed to exist by two scientists who actually set out to disprove its existence. That changed in a "jaw-dropping moment."
• Cocaine Makes Your Brain Eat Brains: Scientists already knew that cocaine killed brain cells, but "autopsies" on the dead brain cells of mice given '70s-rock-star levels of cocaine revealed the cells had been killed when a process went completely bonkers and the cells began, well ... eating themselves.
• Pot Doesn't Make Teens Stupid: That's per a new study on hundreds of pairs of twins—one of whom smoked pot as an adolescent and continued for over 10 years while the other abstained. Scientists found marijuana users lost about four IQ points over time—but their teetotaling twins showed a similar decline. As for declines in specific things such as vocabulary, some other factors appear to be at play.

• This May Be First Evidence of Hunter-Gatherer War: Scientists working on the shores of Lake Turkana in Kenya have uncovered a grisly scene: the bodies of 27 people, killed around 8,000BC. Experts say the spot may be the first to reveal evidence of a massacre—or perhaps even war—between two nomadic hunter-gatherer groups. One clue suggests the attackers came from afar.
• Century Later, Fate of Lost German U-Boat Revealed: A U-boat set off from Germany for a routine patrol with 35 on board on Jan. 13, 1915. It was never seen again. Rumor had it the submarine had washed ashore in Britain with all those on board dead, perhaps due to a gas leak—but that story has now been debunked. The sub lies in 100 feet of water about 55 miles off the coast of Norfolk, England, and it was found by accident.

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