Japan's Hayabusa-2 Probe Prepares To Land On Asteroid Ryugu In February

After an epic 2018 marked by two successful landings on asteroid Ryugu, the Japanese Hayabusa-2 mission is getting ready for its third and most important touchdown on the 3,000-foot-wide space rock.

Launched in 2014, Hayabusa-2 set out to collect and retrieve samples from asteroid Ryugu, a carbon-rich, diamond-shaped space rock located some 180 million miles from Earth. The mission has already landed three spacecraft on the asteroid's rugged surface — a pair of twin 2.4-pound MINERVA-II1 rovers and the 22-pound MASCOT lander, which touched down on the space rock's pitted terrain in September and early October, respectively.

Next up for the Japanese asteroid-sampling mission is a series of three touch-and-go landings performed by the Hayabusa-2 spacecraft itself — with the first one scheduled to take place next month.

As the Inquisitr previously reported, this first touchdown by the Hayabusa-2 probe was originally intended to occur in late October of 2018 but ended up being postponed due to the challenging nature of this endeavor. After obtaining the first close-up views of asteroid Ryugu in June, when Hayabusa-2 finally reached the "Dragon Palace" space rock, the Japan Aerospace Exploration Agency (JAXA) learned that its surface was more rugged than initially estimated and decided to push back the big landing in order to plot a safe touchdown course.

"The time has finally come," JAXA senior project member Takashi Kubota said during a news conference on Tuesday. "Two candidate landing spots have their own advantages and drawbacks, but we will robustly try to collect samples."

According to the Asahi Shimbun, the Hayabusa-2 probe will make its first descent somewhere near the asteroid's equator, with the final landing site due to be chosen by early February.

A total of three possible touchdown locations had been selected for the Hayabusa-2 spacecraft, per a previous Inquisitr report, all of them meeting very specific criteria in terms of surface features and temperature. Each of these potential landing sites is located within 656 feet of Ryugu's equator and represents a flat, 300-foot-wide region that is ideal for accommodating the landing of a fridge-sized spacecraft such as the Hayabusa-2. In addition, all of the suggested touchdown spots are populated by relatively small boulders, less than 20 inches in height.

"For a safe touchdown, it is necessary that there are no rocks bigger than 50-70 centimeters [20 to 27 inches] high around the landing site," the Japan Times reported last week.

The upcoming Hayabusa-2 landing could take place as early as February 18, the mission's team announced via Twitter earlier today.

In September and October, the Hayabusa-2 team conducted a series of landing rehearsals on asteroid Ryugu, during which the scientists managed to lower the spacecraft to about 40 feet above the space rock. Over the course of these rehearsals, which targeted the three potential landing sites, JAXA successfully tested a number of laser sensors that allowed the Hayabusa-2 probe to autonomously orient itself and control its positioning.

"We've got to the point where the only thing left for us to do is make a landing, so we're fully prepared in terms of technique," said Hayabusa-2 project manager Yuichi Tsuda.

The highest-resolution image of asteroid Ryugu, snapped by the Hayabusa-2 probe from a distance of 210 feet away during the landing of the MINERVA-II1 rovers on September 21, 2018.
JAXA, University of Tokyo & collaborators
The highest-resolution image of asteroid Ryugu snapped by the Hayabusa-2 probe from a distance of 210 feet away during the landing of the MINERVA-II1 rovers on September 21, 2018.

During the last week of 2018, the spacecraft returned to the so-called "home position" nearly 13 miles above the asteroid, as shown in the latest update from JAXA's Hayabusa-2 website. From here, the probe will swoop down to Ryugu's surface and use "target markers," dropped beforehand on the space rock's jagged terrain, to guide itself to the landing spot.

Once there, Hayabusa-2 will spend no more than a few seconds on the asteroid's surface — just enough time to deploy its Samper Horn, a 3.2-foot-long cylindrical device designed to fire a copper projectile into the space rock and dislodge sand and rock fragments. The spacecraft will then retrieve the asteroid samples and return to home position, explained JAXA.

"We will carry out the mission carefully yet daringly," said Kubota.