A large flying object expected in December has caught NASA’s attention, but it isn’t Santa Claus’ sleigh. Instead, an asteroid called 3200 Phaethon is projected to come close enough to Earth that it’s been classified as “potentially hazardous” by the International Astronomical Union’s Minor Planet Center. The asteroid has a diameter of about 3 miles, according to NASA, making it the third-largest “potentially hazardous” asteroid to pass by Earth.

NASA expects Phaethon to be the closest to Earth on Dec. 16, when it’s projected to be more than 6.4 million miles away. That’s about 27 times the average distance between Earth and the moon, which is 238,855 miles.  It will be the closest this asteroid has been to Earth since Dec. 16, 1974, when it was just over 5 million miles away, according to NASA. But humans weren’t aware of its presence until later; the asteroid was first discovered in 1983. READ MORE