A group of American scientists discovered the largest potentially hazardous asteroid in over eight years.

A giant asteroid could potentially collide with Earth, according to a group of American scientists, who added that the one they recently discovered is the largest detected in over eight years. The celestial body, dubbed 2022 AP7, is 1.5 kilometres (0.9 miles) wide, according to the team, and its potential impact will be felt across multiple continents.

“So far, we have discovered two large near-Earth asteroids that are about one kilometre across, a size that we call ‘planet killers,'” Scott Sheppard, an astronomer at the Carnegie Institution for Science’s Earth and Planets Laboratory and the lead author of a paper describing the discovery, said in a press release. According to the scientists, only 2022 AP7 has an orbit that makes it potentially dangerous to Earth.

The asteroid known as the ‘planet killer’ was hiding somewhere between Earth and Venus, making it difficult to detect. To study this area, astronomers must look in the direction of the Sun, and cutting-edge orbital telescopes like the James Webb and Hubble cannot be used because the Sun’s glare would burn their sensitive optics.

“Because of the difficulty of observing near the glare of the Sun,” Sheppard explained, “only about 25 asteroids with orbits completely within Earth’s orbit have been discovered to date.” The Dark Energy Camera of the Victor M. Blanco 4-meter Telescope at the Cerro Tololo Inter-American Observatory in Chile was used to make the discovery in this case.

Although the inner solar system is still largely unknown in terms of asteroids, scientists believe that it contains few potential threats to Earth.

“There are likely only a few [near Earth asteroids] with similar sizes left to find,” Sheppard said, adding that the vast majority of them would have orbits that would never put them in direct collision with Earth. It’s also unclear when, if ever, 2022 AP7 will pose a serious threat to Earth.

Despite this, astronomers are already monitoring up to 2,200 potentially hazardous asteroids that are more than one kilometre wide, according to Space.com. According to the media outlet, such space rocks could pose a threat to the entire planet because even a 50-meter-wide asteroid could damage an entire city like London if it explodes over its centre.

Apophis, an asteroid, has a dangerously close orbit to Earth. Scientists warned in 2020 that it could hit the planet in 2068. Later that year, the American Astronomical Society’s Division for Planetary Sciences predicted that the 370-meter-long space rock could pass through the orbits of some of our communication satellites as early as 2029.