“Christmas Eve is going to be a busy night in space for Earth-dwellers. Not only will the International Space Station (ISS) be visible over the U.K. on Christmas Eve, but there will also be a giant asteroid passing over Earth. And Santa’s sleigh will be up there too, obviously. The asteroid, known as both 163899 and 2003 SD220, will pass Earth on Christmas Eve at 8 kilometers (5 miles) per second. While initial reports estimated the asteroid to be between 0.7 and 1.3 kilometers (0.4 and 0.8 miles) in diameter, recent findings from the Arecibo Observatory say it’s more likely to be around 2 kilometers (1.2 miles) in size.”