The Japan Aerospace Exploration Agency (JAXA) has placed the main section of the Hayabusa2 probe on the asteroid Ryugu from this month to January 2019, Nature reported, after mission scientists had determined that the surface of the Ryugu is rougher than expected and the landing needs more planning time.
While Hayabusa2 carries a number of smaller rovers, some of which have already passed. The mothership must land on the surface of the asteroid to collect samples. According to Natura, the JAXA scientists have found that there are only a few boulder fields on the asteroid and the best is very small:
For the sampling phase, the project team had searched for at least one region 100 meters wide would be relatively free of boulders – ie without Stones over 50 centimeters. Otherwise, higher boulders could hit the main body of the vehicle when it uses its 1 meter arm to collect a sample, says a JAXA statement.
But detailed maps of the surface have shown that the best such area is only about 20 feet wide. The agency now wants to make sure it can hit such a narrow target on the rotating surface.
Hayabusa2 will collect samples using a variety of methods; The first run, which is the delayed descent, is performed by shooting the ship to the surface to fire a tantalum orb in Ryugu. After that, loose material is collected through a sampling horn and the aircraft will fire its thrusters to escape the surface of the asteroid. A final collection of samples planned for 2019 involves the remote firing of a kinetic impactor on the asteroid and the detonation of a shaped charge in the distance. (According to Popular Science, the 10 kg of explosives will fire a copper disk in Ryugu in a similar way to military antitank weapons). After no debris has been removed from the impactor for about two weeks, it will sink to the surface to collect samples from the impact site.
"Although the spacecraft can be controlled with a positional error of 10 meters at a height of up to 50 meters, the question remains whether this accuracy can be maintained when the spacecraft descends to the surface," JAXA told Nature a statement. However, JAXA Head of Mission Makoto Yoshikawa from the Sagamihara agency's Space and Astronautics Institute told the magazine that Hayabus' return to Earth in 2020 is unlikely to be delayed, which is good.
According to Nature, JAXA will conduct a test in October to verify that the vehicle can descend safely to the surface:
JAXA says it will be ready from 14-16 May. We will do a touchdown test on October 10 and lower the ship to a height of about 25 meters until today – to test the height measurements of the probe at short intervals.
A close approach of Hayabusa2, which lies within 25 meters, has already been completed this week.
JAXA made a call to delay the landings last week, with project leader Yuichi Tsuda, the Agence France-Press said: "The mission … is going to strike without roc ks." That would be "the hardest," he added, "because we expected the surface to be smooth … but it appears that there is no flat surface. "
At the end of September, Hayabusa's MINERVA-II1A and MINERVA-II1B were rovers (using the torque generated by internal engines to hop instead of relying on wheels), made a successful landing on Ryugu and began to survey their surface. Soon they began to transmit fascinating images of the meteor surface. Ten days later, Hayabusa2 successfully deployed its Mobile Asteroid Surface Scout (MASCOT) observation robot, which included a camera, spectrometer, magnetometer, and radiometer, although its non-rechargeable lithium-ion battery ran slightly more than 17 hours later than planned Touchdown