Holy Einstein! 5 Most Incredible Discoveries of the Week

A huge find in the cosmos and potent pot make the list:

• Gravitational Waves Exist, Guys: Albert Einstein predicted them in 1916, and they were just confirmed—100 years later. Scientists say gravitational waves have been detected, produced by "two colliding black holes that merged to form a single black hole 1.3 billion years ago" and detected by LIGO in September. Find out how LIGO made its find, as well as some reax from a few high-profile fans.

• Today's Pot Is Stronger Than 1995's: Marijuana potency is on the rise, say researchers who analyzed some 38,600 samples of illegal marijuana seized by the DEA over the past 20 years. Not only did samples of a really potent type of marijuana increase from 2010 to 2014: Researchers also found the level of THC (the main psychoactive ingredient in weed) in samples jumped from 4% in 1995 to 12% in 2014; an earlier study in Colorado found some samples contained up to 30%. But why is more potent pot hitting the market?

• How a Woman's Fitbit Gave Her an Enormous Surprise: A couple in New York City have good news to share thanks to wonky Fitbit data and a helpful Redditor. YoungPTone, who identifies himself only as David, posted about issues with his wife's Fitbit on a Reddit thread, suspecting a problem with the device's sensor after it showed a consistently high heartbeat. But a fellow Redditor asked an important question—and David came back online with amazing news.

• After 30 Years, Missing Man Remembers Who He Is: Since 1986, no one knew where Edgar Latulip was. The developmentally disabled man went missing from an Ontario group home in September of that year, and all leads turned up cold. Some thought he may have committed suicide. But Latulip is alive and well, a DNA test has confirmed, and he was discovered after he suddenly remembered his own name out of the blue. Find out where he's been all this time.

• Americans Have Weird Answers When Naming US Presidents: It's Presidents Day weekend, so it's only appropriate to highlight a report that asked 326 participants to pick out 41 US presidents from a list of 123 men in total (82 were "lures," like Alexander Hamilton). So how did America do? Well, in terms of Hamilton, 71% of respondents said they were "fairly sure" he was one of our past commanders-in-chief (he was not). See who else they did, or didn't, pick correctly out of the lineup.

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