Today (Thursday) at around 4:27 PM, a truck-sized asteroid will fly past the southern tip of South America just 2,200 miles above Earth's surface. That's ten times closer to us than the slew of satellites in orbit, a very rare near miss according to NASA's Scout impact hazard assessment system. From NASA's Jet Propulsion Laboratory:
But even if it did [impact Earth], this small asteroid – estimated to be 11.5 to 28 feet (3.5 to 8.5 meters) across – would turn into a fireball and largely disintegrate harmlessly in the atmosphere, with some of the bigger debris potentially falling as small meteorites.
The asteroid was discovered by amateur astronomer Gennadiy Borisov, discoverer of the interstellar comet 2I/Borisov, from his MARGO observatory in Nauchnyi, Crimea, on Saturday, Jan. 21. Additional observations were reported to the Minor Planet Center (MPC) – the internationally recognized clearinghouse for the position measurements of small celestial bodies – and the data was then automatically posted to the Near-Earth Object Confirmation Page. After sufficient observations were collected, the MPC announced the discovery. Within three days, a number of observatories around the world had made dozens of observations, helping astronomers better refine 2023 BU's orbit.
"Scout quickly ruled out 2023 BU as an impactor, but despite the very few observations, it was nonetheless able to predict that the asteroid would make an extraordinarily close approach with Earth," said Davide Farnocchia, a navigation engineer at JPL who developed Scout. "In fact, this is one of the closest approaches by a known near-Earth object ever recorded."