Are Japanese hop robots safe on Ryugu asteroid?

Two small jumping rovers seem to have reached their asteroid target, but we still do not know if they are safe on the surface.

MINERVA-II1A and MINERVA-II1B minirobots separated from their parent ship, the Japanese spacecraft Hayabusa2, as scheduled at 12:06 EDT (0406 GMT) today (21 September) and headed for the large Ryugu asteroid .

The Hayabusa2 team confirmed the deployment of the rovers and established a communication with them soon after. This communication link was lost early this morning – but it was not a reason to panic, mission team members said. [Japan’s Hayabusa2 Asteroid Ryugu Sample-Return Mission in Pictures]

"Communication with MINERVA-II1 is currently halted, this is probably due to Ryugu's rotation, and MINERVA-II1 is now on the other side of the asteroid, and we are currently working to confirm if any images capture the landing of MINERVA-II1, "said Hayabusa2's team on Twitter around 6am (New York time, 10am GMT).

Being isolated from the other side, however, is only a temporary failure. The 900-meter-wide Ryugu rotates every 7.5 hours, so the MINERVA-II1 duo should soon switch to radio if it has not already done so.

We can not assume that everything is fine, of course – landing on an asteroid 200 million miles (300 million kilometers) from Earth is a very delicate matter. For example, it is difficult to put a landing on a body with such light traction, as shown by the experience of the Rosetta mission of the European Space Agency.

In November 2014, the mother ship Rosetta dropped a landing gear called Philae on the surface of comet 67P / Churyumov-Gerasimenko, which is about 4 kilometers wide. Philae was supposed to anchor on the icy surface of the comet with a harpoon, but that did not work and the lander rebounded several times before settling in a shady spot next to the wall of the comet. 39, a cliff. Philae did not have enough light to recharge his batteries as planned and the scientific work of the operator was halted.

The Hayabusa2 engineers are probably doing all they can to greet the MINERVA-II1 bots, but all we can do is wait.

The $ 150 million Hayabusa2 mission was launched in December 2014 and arrived in Ryugu at the end of June this year. The deployment of MINERVA-II1A and MINERVA-II1B – each of them measuring 7 inches wide by 2.8 inches tall (18 by 7 centimeters) and weighs 2.4 pounds. (1.1 kg) – launches an ambitious surface exploration campaign on the big asteroid.

In early October, the orbiter will deploy a larger lander, called Mobile Asteroid Surface Scout (MASCOT). And another small hopper, MINERVA-II2, is expected to head to the surface next year.

Also in 2019, the mother ship will send an impactor (non-explosive) taxiing to Ryugu. The orbiter will then move to the newly created crater and collect a sample of virgin material, previously beneath the surface, that will descend to Earth in a special return capsule in December 2020, if all goes as planned.

Scientists from around the world will study this cosmic gravel and gravel, looking for clues about the beginnings of the solar system and the role that carbon-rich asteroids such as Ryugu have played in the construction of the Earth.

This information will be combined with the data collected by the MINERVA-II, MASCOT and Hayabusa2 orbiter bins.

MINERVA – shortened to "Experimental Micro Robot Vehicle for Asteroids" – is designed to jump because traditional roving does not work well in very low gravity environments. A slight wheel spin would send a robot into space, so jumping is the way to go.

And the hops will be pronounced, they will last about 15 minutes and will cover perhaps 50 feet of horizontal distance each, said members of the Hayabusa2 team.

And about the "II" on behalf of the larvae: The first Hayabusa mission, which was also operated by the Japan Aerospace Exploration Agency and arrived at the asteroid Itokawa in 2005, included a hopper named MINERVA. The original MINERVA failed to land safely on its asteroid target.

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