A NASA probe is collecting images of an unusual-looking asteroid

When NASA’s DART probe hit the moon, the asteroid Dimorphos, on September 27, 2022,
This was a complete mission success
: The object’s orbital period around the asteroid Didymus has been reduced by more than half an hour – more than the participants had hoped for. Shortly before its end, the probe was able to take some pictures of the asteroid and collect data.

Analysis of this material indicates that the asteroid is actively throwing material into space. There are probably millions of other small asteroids doing this as well, and continuously throughout the solar system. This is reported by Nair Trugolo of the University of Alicante and his team over at arXiv.

Brocken rotates on its own axis

Accordingly, Didymus rotates very quickly, and the centrifugal forces caused by this, especially at the equator, are sufficient to lift stones and dust off the surface and fling them into space, where they then float above the surface or orbit around the asteroid. to enter

Once every 2 hours 16 minutes, the part rotates completely around its axis. At these speeds, Didymus is an asteroid “on the verge of settling down,” the authors wrote.

Heavier particles can float for a while after liftoff, land on the surface, break off again, and these same cycles repeat over and over. Or they eventually land at latitudes from which no further take-off is possible.

The impact can become so strong that it rips asteroids apart

Some of the floating rocks will reach orbit, and others may land from a companion to Dimorphos. Even smaller particles may disappear from the system as the solar wind pushes them further into space and out of the asteroid’s gravitational field.

Contrary to what you might think, larger objects stay above the surface longer than smaller ones: the pressure of the solar wind on the side of the daytime asteroid rapidly pushes smaller grains to the surface.

These analyzes are still preliminary and can only be clarified by the HERA mission, which is supposed to reach the system in 2027. According to the working group, the size, shape and composition of the asteroid make this very likely.

The rotation is caused by something called the Yorp effect: the sun heats different parts of an asteroid to different degrees depending on its albedo. This heat is subsequently radiated and produces thrust, which also varies. It’s a small effect, but it builds up over time and can eventually push an asteroid faster and faster.

The impact could eventually become so strong that it rips asteroids apart, as happened in 2013 with P/2013 R3. In Didymus, however, according to current knowledge, this is not imminent in the near future.