Planetary Defense

Since near-Earth asteroid 2024 YR4 was first discovered in December 2024, NASA and the worldwide planetary defense community have continued to observe the asteroid, which was ruled out as a significant impact risk to Earth. New infrared observations from NASA’s James Webb Space Telescope have decreased the uncertainty of the asteroid’s size and 2024 YR4...

NASA has significantly lowered the risk of near-Earth asteroid 2024 YR4 as an impact threat to Earth for the foreseeable future. When first discovered, asteroid 2024 YR4 had a very small, but notable chance of impacting our planet in 2032. As observations of the asteroid continued to be submitted to the Minor Planet Center, experts …

Observations made overnight on Feb. 19 – 20 of asteroid 2024 YR4 have further decreased its chance of Earth impact on Dec. 22, 2032, to 0.28%. NASA’s planetary defense teams will continue to monitor the asteroid to improve our predictions of the asteroid’s trajectory. With this new data, the chance of an impact with the …

Now that skies are darker after a week of limited visibility around full moon, astronomers have resumed observations of asteroid 2024 YR4. Ground-based telescopes require dark skies to observe asteroids, which are often very faint. Around the time of a full moon, the sky becomes too bright to detect these faint points of light. NASA’s …

While still an extremely low possibility, additional observations and analysis of asteroid 2024 YR4 indicate that its impact probability with Earth has increased to a 2.3% chance on Dec. 22, 2032. Ongoing observations from ground-based telescopes involved with the International Asteroid Warning Network will continue while the asteroid is still visible through April, after which …

NASA analysis of a near-Earth asteroid, designated 2024 YR4, indicates it has a more than 1% chance of impacting Earth on Dec. 22, 2032 – which also means there is about a 99% chance this asteroid will not impact. Such initial analysis will change over time as more observations are gathered.    Currently, no other …

The small near-Earth asteroid 2024 PT5 was first observed on Aug. 7, 2024, by the Sutherland, South Africa telescope of the University of Hawai’i’s Asteroid Terrestrial-impact Last Alert System (ATLAS), which is funded by NASA. Estimated to be about 33 feet (10 meters) wide, the asteroid does not pose a hazard to Earth. Because 2024 …

In a world where many global challenges exist, finding ways to respond to an as yet undiscovered asteroid that might one day impact Earth could seem like a lesser priority. While it is true there are currently no known asteroids of significant size on a collision trajectory with Earth, an asteroid impact with our …

On Feb. 15, 2013, the people of Chelyabinsk, Russia, experienced a shocking event, and yet it was a small fraction of the devastation an asteroid on a collision course with Earth could yield. As NASA's Planetary Defense experts reflect on the Chelyabinsk impact 10 years ago, they also look forward to the future and all …