Asteroid Ryugu has no dust on it and we don’t know why

By Abigail Beall

Akihiro Ikeshita/JAXA

The most detailed photos yet of the asteroid Ryugu have published something odd: it’s surprisingly free of mud.

Japan’s Hayabusa 2 spacecraft arrived on the asteroid in June 2018, dropped three landers and took a sample of mud from Ryugu’s surface. Now, photos from one in all the landers have published small print about what the asteroid is made up of.

From outdated observations, scientists knew Ryugu’s composition used to be related to that of a team of meteorites known as carbonaceous chondrites, which rise up lower than 5 per cent of all meteorites that fall to Earth.

However they had been deal surprised regarding the ingredient of rock texture they had been able to gaze on the outside, says Ralf Jaumann on the German Aerospace Center’s Institute of Planetary science in Berlin, who led the look. “Having the ability to witness otherwise colored radiant inclusions within the rock, crumbly surfaces and tranquil textures is unprecedented,” he says.

The photos new there are two forms of rock on Ryugu’s surface, darkish and tough or radiant and tranquil, and they every safe an equal share within the outside.

The photos also new the outside of Ryugu doesn’t have a layer of mud, love there may perhaps be on the moon, as an example. This is odd because mud is anticipated to acquire thru assorted bumps and scrapes in home. Why it isn’t there may perhaps be a mystery.

Akihiro Ikeshita/JAXA

One clarification may perhaps well well be that racy mud particles turn out to be charged ensuing from solar radiation and and are eliminated by electrical forces, says Jaumann. Yet every other possibility is that the originate of unstable gasses from the outside may perhaps well well need blown the mud away. Or presumably, if the asteroid shakes as it travels thru home, the mud may perhaps well well have progressively trickled into the inside the asteroid, which manner we can’t survey it.

“At this point it’s unclear which mechanism, is most doable for Ryugu,” says Jaumann.

Journal reference: science, DOI: 10.1126/science.aaw8627