Potentially dangerous asteroid: NASA and ESA activate reaction groups

Following the discovery of a potentially dangerous asteroid for the Earth, NASA and ESA have activated their designated response teams. This is the usual protocol in the event that an asteroid with a size of over 50 meters and a collision probability of over one percent is discovered, the European Space Agency (ESA) announced. This applies to the celestial body with the designation 2024 YR₄, which was discovered at the end of 2024. Nevertheless, an impact is fairly unlikely: NASA puts the probability of the celestial body passing the Earth at a safe distance at 99 percent.

Possibly on the lists for years to come

The International Asteroid Warning Network (IAWN), coordinated by Nasa, coordinates the work of organizations that observe and characterize asteroids. ESA is also a member of the network and uses the observations to update the risk information. The ESA points out that 2024 YR₄ is currently moving away from Earth and will only be observable for a few more months. If, despite further observations during this time, it cannot be ruled out that it poses a danger to Earth, it will probably remain on the list of the most dangerous asteroids until at least 2028.

In addition to the IAWN, the ESA's Space Mission Planning Advisory Group (SPMAG) has also been activated. Its task is to prepare an international response, if necessary, to a threat posed by a near-Earth object from space. Further steps are to be examined at a scheduled meeting in Vienna next week, should the probability of an impact still exceed one percent. It is also possible that various options for measures involving defense against the asteroid with the help of a spacecraft will already be evaluated.

2024 YR₄ was discovered on December 27 using a telescope in Chile. Follow-up observations have shown that an impact of the asteroid cannot be ruled out during its next but one encounter with Earth in 2032. This is why the asteroid is now at the top of two lists of the currently most dangerous celestial bodies. According to the NASA list, the probability of an impact is now 1.3 percent, slightly higher than on Wednesday. According to the ESA list, however, the calculated distance to Earth during the flyby has recently increased slightly. The asteroid has a diameter of 40 to 90 meters. According to a study from 2017, asteroids can claim victims from a size of 18 meters, from 56 meters they leave craters on the surface.

The US space agency has now also responded and pointed out that the celestial body is being observed. NASA points out that the values still mean that a collision can currently be ruled out with almost 99 percent probability. Usually, more precise measurements later result in greater distances and the calculated risk is reduced, but such high initial values as for 2024 YR₄ have not been determined for a long time. For the asteroid Apophis, a 2.7 percent probability of impact was initially determined over 20 years ago, but a collision has since been ruled out.

(mho)