The James Webb Space Telescope (NASA/ESA/CSA) has taken a unique photo of one of the smallest observable objects in its history – asteroid 2024 YR4. On March 8, 2025, the telescope’s infrared cameras (NIRCam and MIRI) “spotted” a space visitor. The results of the observation proved definitively that the asteroid poses no threat to our planet in 2032 and beyond. However, this space debris has told scientists a whole story about the mysteries of the Solar System.
Features of 2024 YR4
2024 YR4 is only 60 meters in diameter – about as big as a 15-story house. It became the smallest asteroid whose size James Webb was able to measure directly. NIRCam recorded reflected sunlight and MIRI investigated the thermal emission from the surface. This kind of data has helped explain how the object heats, cools, and interacts with solar energy in its orbit.
The analysis showed that 2024 YR4 behaves differently than larger asteroids. Its fast rotation and lack of dust on the surface make it “stubborn” to temperature changes. Instead, its surface is probably covered with rocks the size of your fist or larger. This may explain why it doesn’t retain heat the way dust-covered asteroids do.
The efforts of the international team
Experts from the European Coordination Center for Near-Earth Objects, NASA and international scientists joined the study. Joint observations finally confirmed: the trajectory of 2024 YR4 does not intersect with the Earth. “This is a perfect example of how technology and collaboration reduce collision risks,” the ESA said.
James Webb’s data not only reveal the asteroid’s physical properties, but also complement ground-based observations, improving calculations of its orbit. Although 2024 YR4 has been recognized as safe, its study is a step toward unraveling how small objects in the Solar System formed and evolved. The study will also improve prediction of the motion of other potentially dangerous space debris that may be approaching Earth.
Next time you see a 15-story building, imagine this: somewhere in space is a rock “tower” of that size, 4.6 billion years old, that the human mind has only now deciphered.
Previously, we reported on where asteroid 2024 YR4 could fall.
According to ESA
