It is about the size of a football field and it is heading towards the Earth.
No need to worry, though. It will come close but will not hit us.
"It's going to come within the belt of geosynchronous satellites," says Dr. Edward Albin, the astronomer at the Fernbank Science Center.
Which means the asteroid will be closer to the Earth than the satellite that runs your GPS.
This asteroid, which like others is composed mainly of iron and nickel, comes from the outer reaches of our solar system, from the asteroid belt.
"These minor planets are out there and, once in a while, they collide and one falls into the inner solar system," says Albin, "where it, sometimes, strikes either Mars or Mercury or our moon."
If you're wondering what would have happened if this asteroid hit the Earth, there is evidence here in the U.S.
"Meteor crater, in Arizona, was formed about 50,000 years ago," Albin tells WSB. "A crater like that may form about once every 100,000 years.
"It's about a mile across and 600 feet deep," he says, "and it was formed when the Earth was hit by an object that may have been a little larger than a MARTA bus, or a railroad boxcar."
The most famous asteroid hit was 65 million years ago, an event that killed off most life on Earth.
"The extinction event that wiped out the dinosaurs," says Albin, "we're looking at an object that was much, much larger (than the asteroid that passed by the Earth today). That one was about a half-mile to a mile across."
But make no mistake; having an asteroid this large pass this close is very, very rare.
"In recent times we have not had an object like this pass this closely," says Albin. "It is really an exciting event for the astronomical community."