The Japanese Hayabusa2 is possibly the first probe in history to collect material beneath the surface of an asteroid – a mission that could provide important new insights into the early stages of our solar system. Trying alone is an exciting feat, but we will not know for sure if the probe has successfully collected samples until it returns to Earth next year.
"From the data sent by Hayabusa2, it was confirmed that the placement sequence including the discharge of a sampling projectile was successfully completed," the Japan Aerospace Exploration Agency (JAXA) announced in a press release released today.
The probe made its short landing at 10:06 am Japanese time and works normally, according to JAXA.
This is the second time that Hayabusa2 has visited the surface of Ryugu – an 870 meter wide asteroid that is 300 million kilometers from Earth. The first landing took place last February. During this time, the probe fired a projectile on Ryugu's surface and hurled surface material, which she then collected.
This second visit is noteworthy in that Hayabusa2 attempted to collect materials beneath the surface that had never been done before. Already in April, the probe shot an "impactor", a copper ball, on Ryugu's surface, creating an artificial crater surrounded by underground material. This stuff is valuable to scientists because it is protected from the effects of space weathering, including the effects of cosmic rays and charged particles flowing from the sun. These samples could shed new light on the origins of the solar system and on how it was billions of years ago.
This second operation to visit the surface of the asteroid began on July 9th. Hayabusa's slow journey to the surface began on July 10. When he reached a distance of 30 meters (98 feet), the probe localized a marker, which he had previously filed and his trajectory had adjusted autonomously accordingly. The probe landed briefly at a location known as the C01-Cb region, about 20 meters from the artificial crater.
The placement process itself took only a few seconds. During this time, the probe fired a small projectile on the surface. This created a field of floating debris that fell into the containment pipe (so we hope). Hayabusa2 then returned to a safe distance, where he will continue to monitor the asteroid and sampling site.
This mission was potentially risky as Hayabusa2 had already tried to collect surface samples, and a failure here could have disabled the spaceship and prevented it from returning its precious cargo to Earth. Fortunately, this does not seem to be the case as the mission directors call today's landing "perfect."
"It was a success, a great success," said Takashi Kubota, team member of Hayabusa 2, at a press conference that took place earlier today. as reported by New Scientist. "We have achieved success in all of the planned procedures."
This mission was the last major operation that Hayabusa2 made next to his journey to Earth. The probe is expected to return with its samples by the end of next year.
Interestingly, according to AFP, the sample cans are deposited to re-enter the earth's atmosphere, but the probe itself remains in outer space. JAXA is accordingly considering an expanded mission to send Hayabusa2 to visit another asteroid.