An asteroid the size of a delivery truck will pass close to Earth on Thursday night, one of the closest such encounters ever recorded.
NASA insists that it will be a flyby with no chance of the asteroid hitting Earth.
The agency said Wednesday that this newly discovered asteroid will pass within 3,600 kilometers (2,200 miles) over the southern tip of South America. That's 10 times closer than the group of communication satellites orbiting above.
The closest approach will be at 7:27 p.m. Eastern Time (9:27 p.m. local time).
Even if the space rock got much closer, scientists say almost all of it would burn up in the atmosphere, with some of the biggest chunks possibly falling as meteorites.
NASA's impact risk assessment system, called Scout, quickly ruled out a collision, said its developer, David Farnocchia, an engineer at the Jet Propulsion Laboratory in Pasadena, California.
"But despite very few observations, he was able to predict that the asteroid will come extraordinarily close to Earth," Farnocchia said in a statement. "In fact, it's one of the closest approaches of a near-Earth object ever recorded."
Discovered on Saturday, the asteroid known as 2023 BU is believed to be between 3.5 meters (11 feet) and 8.5 meters (28 feet) across. It was first detected by Gennady Borisov, the same amateur astronomer in Crimea who discovered an interstellar comet in 2019. Within days, astronomers around the world made dozens of observations, allowing them to refine the asteroid's orbit.
The asteroid's trajectory will be drastically altered by Earth's gravity once it passes close. Instead of going around the Sun every 359 days, it will move in an oval orbit that will last 425 days, according to NASA.
