But that also means the space rock has a nearly 99% chance of safely passing by Earth in 2032, according to the ESA and NASA. Future observations of the asteroid will help scientists determine the likelihood of an impact.
The asteroid is estimated to be between 131 and 328 feet (40 and 100 meters) wide. Asteroids of this size impact Earth every few thousand years, and they can cause severe damage to local regions, according to the ESA.
The space rock has a “size range comparable to that of a large building,” said Dr. Paul Chodas, director for the Center for Near Earth Object Studies, or CNEOS, at NASA’s Jet Propulsion Laboratory in Pasadena, California. Chodas added that the actual size of the asteroid, which astronomers are trying to determine with follow-up observations using multiple telescopes, is currently highly uncertain.
“If the asteroid turns out to be on the large end of its estimated size range, the impact could produce blast damage as far as 50 kilometers (31 miles) from the impact site,” Chodas said. “But that’s in the unlikely event that it might impact at all. The potential for damage arises because of the incredibly high speed (about 17 kilometers per second, or 38,028 miles per hour) at which the asteroid would enter the atmosphere.”
Spotting an asteroid that’s new to science
The Asteroid Terrestrial-impact Last Alert System, or ATLAS, telescope located in Rio Hurtado, Chile, first spied the space rock on December 27. The telescope is one of the asteroid discovery programs funded by NASA to scan the sky in search of near-Earth asteroids, said Davide Farnocchia, navigation engineer at JPL and CNEOS.
“The discovery happened while the asteroid was in the Earth’s neighborhood, which made it bright enough to be detected,” Farnocchia said.
Automated asteroid warning systems sent out an alarm after determining the asteroid had a slim chance of impacting Earth in 2032, bumping it to the top of the ESA’s asteroid risk list and NASA’s automated Sentry risk list on December 31. Such lists include any known asteroids with a nonzero probability of colliding with Earth.
Since early January, astronomers have used the Magdalena Ridge Observatory in New Mexico, the Danish Telescope and the Very Large Telescope in Chile to track the asteroid, which is currently 28 million miles (45 million kilometers) from Earth and moving farther away over time, Farnocchia said. The observations can also help researchers refine their estimates of the asteroid’s size and trajectory.
As the asteroid moves away from Earth and becomes fainter, researchers will have to rely on larger telescopes to observe it. The celestial object should be visible through early April, and as it continues on its orbit around the sun, it won’t return to Earth’s vicinity until 2028, Farnocchia said.
If 2024 YR4 disappears from view before space agencies can entirely rule out any chance of impact, the space rock will remain on the risk list until it’s back in view in 2028.
“Using the available tracking data, we can predict the future position of an asteroid,” Farnocchia said. “The longer we track an asteroid, the more precise the prediction. As we collect additional data, the uncertainty in the position of 2024 YR4 in 2032 will decrease. Given that the impact probability is only 1%, it is 99% likely that the Earth will eventually fall outside the swath of possible positions and that the probability would fall to zero.”
cnn
