A few hours ago the Japanese space probe Hayabusa 2 touched down on the soil of asteroid Ryugu to collect some subsurface samples that will be transported to Earth. This is the second attempt of the three possible at the start of the mission. After the first sample taken on February 22, 2019, the Japanese space agency JAXA decided to proceed with a second attempt in another area to then finish Ryugu’s study and return to Earth with the samples taken.
The Hayabusa 2 space probe reached the Ryugu asteroid between June 26 and 27, 2018. The landing of some small rovers called Minerva and the lander Mascot and the study from the orbit allowed to start understanding this asteroid’s characteristics, including the soil’s, to find the areas most suitable for touchdown attempts, to take samples.
The gravelly surface of the asteroid Ryugu made the preparations for the sample collection operations more complex but on February 22 the first attempt was successful. The choice of the second area for the descent of the Hayabusa 2 space probe was even more difficult and finally went to the area classified as C01-Cb. In addition to the dangers of the rocks on the ground, the dust raised during the operation carried out on April 5 to create a crater in the area could create some visibility problems. Due to the distance, it’s impossible to remote control Hayabusa 2 so the operation is automated and if the onboard systems are deceived by dust it’s not possible to intervene.
Despite the risk of collision with some rocks, the mission control center decided to proceed because it’s the first time that a space probe has taken samples of an asteroid from two different areas. In essence, from a scientific point of view it was worth taking the risk. At this point, however, a third attempt would add nothing, so it was decided to cancel it.
The second descent was defined a success at the mission control center. The taking of materials raised in April after the creation of a crater with the Small Carry-on Impactor (SCI) projectile should enable obtaining samples of asteroid Ryugu’s subsoil. The hope is to have obtained during the two descents both samples of regolith, the superficial layer, and of the subsoil to be analyzed and compared to understand also the effects of the exposure to space with solar wind and cosmic rays.
JAXA has also confirmed that after the descent and the attempt to capture materials, the Hayabusa 2 space probe has regularly begun the maneuvers that will bring it back slowly into orbit. This part of the mission is completed while the operations in orbit will be completed in the coming months. According to the schedule, Hayabusa 2 will begin its return journey to Earth in December 2019, which should take about a year.