Scientists expect the impact formed a crater 2 meters in diameter (6.5 feet), large enough to reveal subsurface materials that are to be brought back to Earth for analysis.
Scientists will have to wait until later this week to see whether the experiment succeeded. Hayabusa2 returns then to the site, having ducked for cover on the other side of the asteroid to avoid impact with resulting debris.
“We expect that very small fragments will meanwhile have their orbits disrupted by solar radiation pressure – the slow but persistent push of sunlight itself,” said in a statement Patrick Michel from the Côte d'Azur Observatory, a scientist working for the Japanese mission.
“In the meantime we’ve also been downloading images from a camera called DCAM3 that accompanied the SCI payload to see if it caught a glimpse of the crater and the early ejecta evolution.”
These downloaded images have been compiled in a short video showing in slow motion the descent of the slug toward the surface.
This month’s experiment is not the first one conducted by Hayabusa2. In September 2018 two tiny robots landed on Ryugu’s surface on a mission to collect samples and return them to Earth.
This video shows the descent of the SCI (Small Carry-on Impactor) made from images captured at 2 second intervals just after separation from Hayabusa2 by the onboard TIR (Thermal Infrared Camera). In the background, you can see the surface of Ryugu 500m away. pic.twitter.com/O5niPDb2XI— [email protected] (@haya2e_jaxa) 21 aprilie 2019