Summary:
Black Friday is a day when many people spend the day after Thanksgiving hunting for the best deals, but on Friday, NASA scientists had their own ""Black Hole Friday.""

Full article:
(CNN) -- Black Friday bargain hunters, do you ever get the feeling that you're being sucked in somewhere against your control, rapidly descending to a dark, cold place? It could be that feeling after you snatch the last Xbox away from a 9-year-old. Or it could be a black hole. Shoppers may have Black Friday, but NASA scientists have something that's arguably better: Black Hole Friday. NASA spent the day tweeting facts about black holes, including a handful of Black Friday-themed jokes. If humor isn't your thing, the agency also tweeted out a black hole-themed game. The space agency sent out over a dozen tweets and retweets on black holes. The "2-for-1 deal" was a hit, garnering over 1,000 retweets. NASA defines a black hole as "a place in space where gravity pulls so much that even light cannot get out," where "the gravity is so strong because matter has been squeezed into a tiny space." The space agency also posted some fun and less-known facts about black holes: For example, some scientists believe that the smallest black holes are the size of a single atom.