Hayabusa-2: Japan hopes a historic landing of asteroids

The Japanese Space Agency (JAXA) estimates having successfully landed two robotic explorers on the surface of an asteroid, doing the story.

"We have no confirmation yet, but we are very, very optimistic," said project director Yuichi Tsuda.

On Friday, the spacecraft Hayabusa-2 sent a pair of "rovers" to the rock of the 1 km space called Ryugu.

Rover 1A and Rover 1B will bypass Ryugu's low gravity, capturing surface temperatures and images.

Hayabusa-2 reached the Ryugu asteroid in June of this year after a trip of three and a half years.

Officials hope to confirm a successful landing in a day or two, when the spacecraft will send rovers data to Earth.

Why is it important?

While the European Space Agency had already managed to land on an icy comet, it would be the first space ship to successfully place robots on the surface of an asteroid.

Asteroids are essentially remnants of building materials from the formation of the solar system 4.6 billion years ago.

Ryugu is a particularly primitive variety, and his study could shed light on the origin and evolution of our planet.

The diamond-shaped asteroid has a blackish-colored surface and rotates slowly on its axis – about once every 7.5 hours.

How did the rovers hit the asteroid?

Early Thursday morning (GMT), Hayabusa-2 began to descend to Ryugu's surface, preparing to eject his rovers.

The small hoppers are stored in a drum-shaped container at the base of the "feeder". Collectively, they form a 3.3-kg scientific ensemble called Minerva II-1.

At about 60 meters from the asteroid, Hayabusa-2 launched the launch of the two robots.

Officials at the Japanese space agency said that when the drum 's front is dropped into space, both rovers are ejected from the container and fall independently onto the surface of the asteroid.

One of the main concerns regarding the deployment was Ryugu's rougher surface than expected, which is carpeted with rocks and has very few smooth slabs.

What will they do there?

The 1 kg rovers are equipped with wide angle and stereo cameras to return images of Ryugu. The spine-shaped projections of the edges of the hoppers are sensors that measure surface temperatures on the asteroid.

They can jump and float thanks to a motorized internal rotor that propels the robot on the surface.

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They will return their data to the tanker, who will then transmit the information to the Earth.

"I am looking forward to seeing pictures, I want to see images of the space seen from the surface of the asteroid," said Yuichi Tsuda, JAXA Project Manager.

When will they get samples?

On 3 October, the tanker will deploy a lander called Mascot, developed by the German Aerospace Center (DLR) in collaboration with the French Space Agency (CNES).

And at the end of October, Hayabusa-2 will come down to the surface of Ryugu to collect a sample of rock and soil.

Further in the mission, the Japanese space agency plans to detonate an explosive charge that will strike a crater on the surface of Ryugu.

Hayabusa-2 would then descend into the crater to collect fresh rocks that had not been altered by exposure to the space environment.

These samples will be sent to Earth for laboratory studies.

The spacecraft will leave Ryugu in December 2019 with the intention of returning to Earth with the asteroid samples in 2020.