Undetected Refrigerator-Sized Asteroid Sails 2,000 Miles Past Earth

by Jennifer Shea
Nicolas Economou/NurPhoto via Getty Images

Now that’s a close call. An asteroid whizzed by Antarctica this week, getting within 2,000 miles of the continent.

The asteroid was about as big as a refrigerator or golf cart. But it came within 1,800 miles of the southern hemisphere. And it went undetected by scientists until the Catalina Sky Survey noticed it, the New York Post reports.

The close call was reportedly the third nearest flyby of a foreign object that didn’t result in an impact.

Asteroid Would Have Been Burned Up by Earth’s Atmosphere

Scientists have dubbed the object Asteroid 2021 UA1. Had it come even closer to Earth, the asteroid probably would have burned up in the Earth’s atmosphere, according to CNET.

For example, a meteorite that impacted Russia in 2013 did in fact mostly burn up when it hit the Earth’s atmosphere. Unfortunately, it gave off 500 kilotons of energy as it did, shattering windows across the city of Chelyabinsk. Still, the meteorite, which was 20 times the size of this asteroid, was whittled down to the size of a large rock by the time it got through our planet’s atmosphere.

The asteroid ultimately soared past Antarctica on Sunday evening. It coasted past at an altitude nearer than the communications satellites in geostationary orbit, but farther than the International Space Station. It came from the sun’s general direction, which is why astronomers missed it at first.

NASA has a pending mission, the NEO Surveyor, which aims to take care of that potentially dangerous blind spot.

NEO Surveyor Infrared Space Telescope Tracks Dangerous Objects

In 2010, Congress told the National Aeronautics and Space Administration (NASA) to track down 90 percent of near-earth objects (NEOs) larger than 459 feet in size. Thus the NEO Surveyor mission was born. The Surveyor is an infrared space telescope. And it has a sunshade that allows it to spot earth-approaching objects.

University of Arizona astronomy professor Amy Mainzer is leading the mission. It’s currently in the preliminary design phase. And it will ultimately find, track and classify potentially dangerous asteroids and comets.

“We think there are about 25,000 NEOs large enough to wipe out an area like Southern California,” Mainzer said in a press release. “Once they get bigger than about 450 feet in diameter, they can cause severe regional damage. We want to find these, and as many smaller ones as possible.”

Scientists on the mission will track down NEOs by their heat emissions. That will also enable them to calculate how big the objects are. (The energy of an object’s impact is determined by its size.)

“Earth-approaching asteroids and comets are warmed by the sun, and they give off heat that the NEO Surveyor mission will be able to pick up,” Mainzer added. “Even asteroids as dark as a chunk of coal won’t be able to hide from our infrared eyes.”

Hopefully, thanks to missions like the NEO Surveyor, the next object to pass close by the Earth won’t come as a surprise to astronomers.