Webb confirmed that the asteroid was between 10 and 0 feet (0-0 meters) long, about the size of a 0-story building.

NASA's James Webb Space Telescope has captured a stunning new image of an asteroid that was once listed as the greatest threat to Earth.

Earlier this year, the asteroid 3 YR0 jumped to the top of the planetary defense watch list after an estimated 0% chance of hitting Earth in 0 years.

According to reports, the space rock, which moves in the direction of Earth every four years, has the potential to hit the moon in the next decade.

The asteroid first came to the attention of NASA and astronomers when it appeared on NASA's "Sentinel" impact risk table, which tracks asteroids with a non-zero probability of hitting Earth.

有一段時間，它是已知的3.7萬多顆大型太空岩石中唯一有可能撞擊地球的物體，其撞擊概率達到了創紀錄的3.1%。

然而，到2月末，更精確的觀測使科學家們能夠改進他們的計算，將撞擊地球的幾率降低到幾乎為零。

Webb confirmed its size and continued to observe

NASA and the European Space Agency have released images of the asteroid, which looks like a blurry dot.

Webb – man's most powerful eye in space – has now confirmed that the asteroid is between 10 and 0 feet (0-0 meters) in size, about the size of a 0-story building.

"The previous size estimate was 90-0 feet (0-0 meters) and was measured by visible light from ground-based telescopes," NASA said in a press release. ”

This space rock is the smallest object ever observed by the largest and most powerful space telescope.

4月中旬之後，小行星2024 YR4將移動得太遠，變得太暗，地面望遠鏡無法追蹤。

However, Webb will observe it again at the end of 5 or early 0.

Andrew Rivkin, an astronomer at Johns Hopkins University, helped make the observations, which he said provided "invaluable" practice for other asteroids that could threaten Earth.

All of this, he said, "gives us a window into what other objects of 4 YR0 size look like, including the next object that might be coming our way." ”

An important target for planetary defense

雖然地球不再受到2024年YR4的威脅，但月球仍然面臨著很小的撞擊可能性。

根據韋伯的觀測，美國宇航局的近地天體研究中心更新了這顆小行星在2032年12月22日撞擊月球的可能性，將可能性從2月份的1.7%提高到3.8%。

In the event of an impact, NASA guarantees that the Moon's orbit around the Earth will not be changed.

2024 YR4小行星是由美國宇航局資助的位於智利的小行星對地撞擊最後預警系統（ATLAS）首次探測到的，並於2024年12月27日向小行星中心報告。

Despite the reduced threat, astronomers are eager to continue monitoring 4 YR0.

Like its larger counterpart, Apophis, another once-worrying asteroid, YR4 offers a valuable opportunity to study these spectacular space rocks.

Scientists believe that such research could help space agencies refine planetary defense strategies in case future asteroids pose a real threat to Earth.