Discover space! Every day, new images or photographs of our amazing Universe are published along with a short explanation written by a professional astronomer.
2026 June 30
Explanation:
Why are parts of this asteroid’s surface so smooth? The answer most likely has to do with the dynamics of the asteroid, which is a pile of debris rather than solid rock. The unusual asteroid Itokawa was visited by Japan’s Hayabusa spacecraft in 2005, which photographed and documented its unusual structure and mysterious lack of craters. Analysis of the boundary regions between smooth and rough areas suggests that asteroid impacts can create separation between large and small rocks near the surface, similar to the Brazil nut effect. The Hayabusa robot landed on one of the smooth areas, called the Sea of ​​MUZ, and collected soil samples. These samples were returned to Earth and provide clues not only to the ancient history of this unusual asteroid, but also to the early years of our entire solar system. Computer simulations show that the 500-meter asteroid Itokawa could collide with Earth within the next few million years.