The Japan Aerospace Exploration Agency (JAXA) has released captivating footage of the Hayabusa 2 spacecraft descending and making contact with the primordial asteroid Ryugu. During the rendezvous, the probe shot a bullet into the surface to kick up a sample for return to Earth sometime late in the year 2020.
Hayabusa 2 finally arrived at Ryugu on June 27, 2018, having survived a three-and-a-half-year journey through the hostile environment of deep space. Following months of observation and characterization of the asteroid, Hayabusa 2 was given the green light to begin its historic descent to the surface of the ancient alien body on February 22 this year.
Both the asteroid itself and Hayabusa 2's rendezvous area have been given names from the Japanese fairy tale Urashima Tarō. In the story, Ryugu was the name of a dragon king's palace that existed at the bottom of the ocean. The landing site was unofficially dubbed Tamatebako, was the name given to a sacred treasure box of great value that rested within the palace.
Upon being opened in the fable, smoke emerged from Tamatebako. Members of the ambitious mission thought this would be a fitting name, as a cloud of dust would be kicked up by the thrusters of the probe upon leaving the asteroid's surface, and that the sample returned also represents a priceless treasure.
The camera tasked with recording the dramatic dive was funded by donations from the public. The instrument began continuously recording the descent when the probe was 59 seconds away from impact, travelling at a rate of 7 cm/s relative to the asteroid.
The footage, which is played at five times its original speed, shows Hayabusa 2 descending, kicking up a large cloud of debris, and subsequently soaring away. Upon touching down, the probe fired a projectile into the ground, propelling matter into the air that was then captured in the spacecraft's "sampler horn."
During the encounter, the hauntingly bleak surface of Ryugu was captured in incredible detail, with smaller features becoming ever clearer as the spacecraft's shadow grows larger. The flying debris observed in the video was created by a combination of the metal projectile slamming into the asteroid, and the pressure of the probe's thrusters as it pushed itself back away from Ryugu.
A scientific analysis of the imagery is still in progress, but based on initial impressions, JAXA is confident that the potential for sample collection was high.
The sampler horn was seemingly able to make contact with the surface without striking any large stones. Following the impact, rocks with a diameter of several tens of centimetres in diameter were sent shooting outward.
The next major mission milestone for Hayabusa 2 will see the probe create a larger artificial crater on Ryugu by striking the asteroid's surface with a small copper weight. This operation is currently scheduled to take place in the first week of April. The probe will then descend once more to collect another sample from the newly-exposed interior of the comet sometime after May.
Following the second sample recovery, a third landing is possible, though JAXA has stated that there is a high probability that this final descent is unlikely to happen.
Hayabusa 2 is expected to bid farewell to Ryugu in November, or possibly December, and begin a year-long journey home. Hopefully, the culmination of this epic voyage in the closing months of the year 2020 will see the return of precious asteroid samples descending through Earth's dense atmosphere, nestled safely in a protective capsule.
While Urashima was warned never to open his Tamatebako lest something dreadful happen, scientists back on Earth will have no such dire warning to contend with. They will be free to lift the lid off their treasure, and potentially shed light on the nature and formation of our solar system.
Source: JAXA