It's supposed to be about Monday's death of former British Prime Minister Margaret Thatcher and looks to have been popularized by the website "IsThatcherDeadYet," which was not upset to hear about the Iron Lady's passing. "It's fair to say that we are not fans," site co-creator Jared Earle told The Guardian.
When Thatcher died, the website asked readers "how are you celebrating?" and suggested they use the #nowthatcherisdead hashtag.
Monday at 7:58 a.m. ET, just after the news broke of Thatcher's death, the hashtag popped up on Twitter. The first tweet from someone who seemed to have read it wrong came four minutes later:
"So sad to hear that Cher is dead. #nowthatcherisdead."