It began with a cryptic announcement of a press conference in Brazil where "an international team of astronomers" would announce "a surprise discovery in the outer solar system."
If that sounds intriguing to you, you're not alone. In the 27-odd hours between the time the heads-up reached folks' email in-boxes and the press conference (which kicks off at 3 p.m. local time (11 a.m. PDT) at Brazil's National Observatory in Rio de Janeiro), clever people took to Twitter to make their best guesses about what this surprise discovery might be.
The predictions make reference to the ill-fated Comet ISON, Neil deGrasse Tyson's reboot of "Cosmos," the Voyager spacecraft and even the 1990s sitcom "Friends."
Below are some of our favorite predictions: