Space agencies are keeping an eye on a recently discovered asteroid that has a small chance of hitting Earth. Called 2024 YR4, the celestial body has a 1.2% chance of hitting the planet on December 22, 2032, discovered the European space agency and NASA. But it also means that the space rock has almost 99% chance of safely passing through the earth in 2032, according to ESA and NASA.
Future observations of the asteroid will help scientists determine the likelihood of an impact. It is estimated that it has between 40 and 100 meters wide. Celestial bodies of this size impact Earth every few thousand years and can cause serious damage to local regions, according to ESA.
A has a “range of size comparable to that of a large building,” said Dr. Paul Chodas, director of the Center for Near Earth Object Studies, or Cneos, at the NASA jet propulsion laboratory in Pasadena, California.
Chodas added that the actual asteroid size, that astronomers are trying to determine with follow -up observations using various telescopes, is currently highly uncertain.
“If the asteroid is at the larger end of its estimated size range, the impact can produce explosion damage up to 50 kilometers from the impact site, but this is unlikely to impact. The damage potential arises because of incredibly high speed (about 17 kilometers per second) in which the asteroid would enter the atmosphere, ”he said.
Sighting a new asteroid for science
The Asteroid Terrestrial-Impact Last Alert System telescope, or Actals, located in Rio Hurtado, Chile, spotted the space rock for the first time on December 27. The telescope is one of NASA -funded asteroid discovery programs to scan the sky in search of asteroids near Earth, said Davide Farnocchia, JPL and Cneos navigation engineer.
“The discovery happened while the asteroid was in the vicinity of the Earth, which made him bright enough to be detected,” Farnocchia said.
Automated asteroid warning systems sent an alarm after determining that the space rock had a small chance of impacting Earth by 2032, placing it on the top of ESA’s asteroid risk list and NASA’s automated risk list in 31 December. These lists include any known asteroids with different probability than zero to collide with the 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 45 million kilometers from Earth and increasingly away with Time, said Farnocchia.
Observations can also help researchers refine their estimates of asteroid size and trajectory.
As the asteroid moves away from the earth and becomes weaker, the researchers will have to have larger telescopes to observe it. The celestial object should be visible until early April and, as it continues in its orbit around the sun, will not return to the vicinity of the Earth until 2028, Farnocchia said.
If 2024 YR4 disappears from sight before space agencies can completely discard any chance of impact, the space rock will remain on the risk list until it is back in cash in 2028.
“Using available tracking data, we can predict the future position of an asteroid. The more time we track an asteroid, the more accurate is the forecast. As we collect additional data, uncertainty in the position of 2024 YR4 by 2032 will decrease. Given that the probability of impact is only 1%, it is 99% likely that the earth will fall out of the possible position range and that probability falls to zero, ”said Farnocchia.
It is not uncommon for the likelihood of an asteroid’s impact to increase shortly after its discovery before this probability falls to zero after scientists learn more about its size and trajectory, according to the European space agency.
NASA and ESA regularly trace thousands of asteroids near Earth, but depending on the size, they are not always easy to detect. But improvements in asteroid research technology and future asteroid observation missions can detect the space rocks that astronomers could not see in the past.
Currently, there are no other large known asteroids that have more than 1% chance of impacting the earth, according to NASA.
Tracking a potential threat
Two international group response to the United Nations endorsed – NASA’s International Asteroid Warning Network and Space Mission Planning Advisory Group, chaired by ESA – were activated in response to threat level.
International Asteroid Warning Network is responsible for coordinating the organizations involved in tracking and characterizing asteroid details – and, if necessary, develop strategies to evaluate the consequences of an impact. Meanwhile, Space Mission Planning Advisory Group, currently gathering at a meeting already planned in Vienna until next week, will provide recommendations and evaluate options on mitigating a potential impact if asteroid remains a threat.
Mitigation tactics include diverting the asteroid to space or evacuating potentially impacted regions on the ground, Farnocchia said.
NASA performed Double Asteroid Redirection Test, called, in September 2022 to evaluate the effectiveness of asteroid deflection technology. The agency wanted to see if a kinetic impact – such as intentionally colliding a spacecraft with an asteroid 6.1 kilometers per second – would be sufficient to change the movement of a celestial object in space
. The spacecraft successfully Darted the way a small asteroid named Dimorphos moves, changing the orbital period of the lunar asteroid – or how long it takes a single revolution around a larger space rock called Didymos – in about 32 minutes.
Neither dimorphos nor didymos pose a danger to the earth. Still, the double asteroid system was a perfect target for testing deflection technology because dimorphos size is comparable to asteroids that can threaten our planet.
Now an ESA mission named Hera is on the way to evaluate the consequences of DART’s impact to determine whether the collision only left a crater behind or if the time of the spacecraft has completely remodeling Dimorphos.
Both agencies see the mission as a step necessary to understand the end result of Daer’s deflection test. Measuring Daer’s efficiency is crucial if a similar strategy needs to be used against an asteroid in a collision route with the earth in the future.
“If 2024 YR4 were still a threat at the end of the current observation window, mitigation measures could be considered,” said Farnocchia. “But talking about mitigation is premature. The priority now is to continue observing 2024 YR4 and reduce your positional uncertainties by 2032, as this will probably discard the impact. ”
