Only four days after it was discovered, an asteroid raced through the earth at a distance of only 16,700 miles.
The asteroid, known as 2021 GW4, traveled 18,700 miles per hour as it passed our planet – nine times faster than a rifle bullet.
At its closest point, GW4 2021 passed us at just 7 percent of the distance between the earth and the moon. It was also much closer to us than some man-made geostationary satellites, which usually orbit about 22,000 kilometers. The closest pass of the asteroid occurred at 09:01 ET.
Astronomer Gianluca Masi, founder of the Virtual Telescope Project, wrote on his website that the asteroid is “extremely close” to Earth.
According to NASA statistics, astronomers believe that the space rock is between 3.5 and 7.7 meters wide, which means that it is relatively small.
Because of its size, the asteroid was not visible to the naked eye when it passed by, but amateur astronomers were able to capture it with telescopes.
The photo below was taken by the Masi just after 20:00 ET on Sunday with a single 180-second exposure on a PlaneWave 17-inch telescope.
Gianluca Masi / Virtual Telescope Project
GW4 of 2021 can be seen as a single white dot in the center of the photo, highlighted with an arrow. At the time, it was about 186,000 miles away. The vague lines are caused by the light of stars as the telescope moves to detect the asteroid.
Masi wrote that the approach of GW4 in 2021 is safe. “Asteroids of this size that come so close are relatively rare, but so far this year we have had four objects coming within 0.07 lunar distance of the Earth’s center: 2021, GW4 is the largest of these four rocks,” he said.
Sometimes asteroids affect the Earth’s atmosphere, and they tend to explode in the air due to the violent forces caused by their speed.
In October 2008, the 2008 asteroid TC3 exploded in the air over Sudan with a power of about 1,000 tons of TNT.
The space rock was detected just one day earlier by Richard Kowalski on the Catalina Sky Survey. Astronomers then predicted when and where it would land, and NASA said at the time that the forecast highlighted “the successful evolution of the Near-Earth Object program”, which follows the orbits of asteroids that are considered near our planet.
NASA’s center for near-Earth object studies has so far discovered more than 25,000 asteroids. It is estimated that about 1,000 are larger than 1 km, but most are smaller.