Recent calculations by NASA suggest that asteroid 2024 YR4, previously believed to be on a collision course with Earth, may actually impact the Moon. This asteroid, comparable in size to a 10-story building, has been assessed to have just over a 4% chance of colliding with the Moon in approximately seven years.
The potential close encounter and possible impact of YR4 with the Moon present an invaluable opportunity for planetary defense research. This event could serve as a crucial learning experience to develop techniques for deflecting asteroids that might threaten Earth in the future. In September 2022, NASA successfully conducted the Double Asteroid Redirection Test (DART), marking a significant milestone in planetary defense technology. The mission involved impacting asteroid Dimorphos, resulting in a successful alteration of its orbit.
Following the DART mission, another spacecraft known as Hera is currently en route to Dimorphos to gather data on the outcomes of the impact. Developed by OHB in Bremen, Germany, the Hera mission aims to further enhance our understanding of asteroid deflection strategies. As part of this ongoing effort, plans are underway to potentially redirect YR4, with a possible launch for the mission targeted for 2028.
Asteroid 2024 YR4 is part of a larger group of approximately 20,000 Apollo-type asteroids that orbit the sun at a distance similar to that of Earth. Initial observations of YR4, conducted in December, raised concerns about a possible impact with our planet. The International Asteroid Warning Network issued a warning on January 29 after calculations from NASA's Jet Propulsion Laboratory (JPL) and the European Space Agency (ESA) suggested that YR4 had a 1.3% chance of impacting Earth.
To address these concerns, astronomers organized dozens of follow-up observations using various telescopes, which ultimately allowed them to rule out the potential for an Earth impact.
For those interested in the ongoing study of asteroid 2024 YR4 and its implications for planetary defense, additional articles include:
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