An asteroid just came incredibly close to Earth

January 27, 2023

An asteroid just hurtled past Earth in an event described by NASA as “one of the closest approaches by a near-Earth object ever recorded.”

Asteroid 2023 BU zipped by at 7:27 p.m. (4:27 p.m. PT), passing over the southern tip of South America a mere 2,200 miles from Earth’s surface — a distance that put it well within the orbit of geosynchronous satellites.

The space rock, which is estimated to be 11.5 to 28 feet (3.5 to 8.5 meters) across, never posed any risk to Earth, NASA said. The space agency explained that even if it had been on a direct path with our planet, it would’ve turned into a fireball and mostly disintegrated in the atmosphere, “with some of the bigger debris potentially falling as small meteorites.”

The asteroid was first sighted by amateur astronomer Gennadiy Borisov as he looked out from an observatory in Crimea last Saturday. Following additional sightings by observatories around the world, astronomers were able to nail down 2023 BU’s orbit.

Once it had enough data, NASA’s Scout impact hazard assessment system, operated by the Center for Near Earth Object Studies at the agency’s Jet Propulsion Laboratory, was able to confirm that the approaching asteroid would miss Earth.

“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.”

Earth’s gravity will have shifted the asteroid’s path, sending it into a new orbit that will see it circle the sun every 425 days instead of every 359 days.

While 2023 BU was fairly small and ended up passing Earth, scientists recognize that much larger asteroids pose a serious threat to our planet. That’s why they’re working on a system to change the path of hazardous asteroids. It involves smashing a spacecraft into the rock to nudge it into a new path, away from Earth. Last year, NASA tested the system on a non-hazardous asteroid and the mission proved a success. Scientists are now working to refine the technology, while also improving ways of identifying potentially dangerous asteroids.

But rest assured, NASA isn’t currently predicting any major asteroid calamities in the coming years.

Still, if you want to find out more about the kind of mess that a major strike could cause, then check out this online simulator that made headlines a couple of months ago.