Japan's space probe Hayabusa 2 landed on an asteroid just over 200 million kilometers from Earth. He shot a bullet to collect a rocky sample and tackled one of the mission's most difficult maneuvers before returning the asteroid sample to scientists on the ground in December 2020.
The spacecraft paused only a few moments on Ryugu's surface before firing engines to get off the asteroid. The ground team of Hayabusa 2 in Sagamihara, Japan celebrated when radio signals were reflected back from the probe. The touch-and-go maneuver went smoothly and enthusiastically engineers who had carefully planned and then redesigned the spacecraft landing.
] "The hand of humanity has reached a new star today," said Yuichi Tsuda, Project Manager of Hayabusa 2 at the Japan Aerospace Exploration Agency (JAXA), about a translator. "JAXA was successful in the operation (and) landing of Hayabusa 2 in Ryugu and the Ryugu sample collection."
Hayabusa 2 was on his own and crashed at a glacial speed towards Ryugu on Thursday, at his expected altitude and altitude Speed reached before contacting the surface at 2229 GMT (17:29 EST). Nineteen minutes later, a shift in the signal coming from Hayabusa 2 showed that it reached the surface and began its ascent, which was applauded by the thoughtful scientists in the control room.
The probe's navigation system autonomously tracked the position of a target marker The surface of the asteroid allows Hayabusa 2 to fire its control jets and steers the aircraft to a narrow landing zone surrounded by dangerous boulders.
At a press conference a few hours later, the JAXA mission officials confirmed that the spacecraft had gone flawlessly during the touch-and-go landing.
The telemetry of Hayabusa 2 showed a temperature rise inside the cabin tantalum projectile weighing 0.2 ounces (5 grams), which shot in the asteroid. The probe used explosives to fire the ball, and the mission managers testified that the temperature increase indicated the unit was working as intended.
The projectile was to fire as a sample horn emanating from Hayabusa 2 touched the surface of Ryugu. The rock and powder ejected from the impact of the projectile would move through the sample horn into one of three chambers in the spacecraft's back capsule, returning the samples to Earth in 2020.
Hayabusa 2, we were able to confirm that the sequence for setting up Hayabusa 2, including the sample collection bullet, has been implemented and the status of Hayabusa 2 is normal, "Tsuda said in a press conference at the Sagamihara Control Center.  The officers planned to seal the chamber with the samples from the landing on Thursday to ensure that the material was not contaminated during the return journey to Earth.
Hayabusa 2 is Japan's second mission to collect samples from an asteroid for the return to Earth.
A The predecessor probe, Hayabusa, flew to the asteroid Itokawa, but only collected microscopic specimens of the object after encountering numerous problems, including a malfunction in its own project response system, fuel leak, and reaction wheel failure. Hayabusa, meaning "peregrine falcon" in Japanese, returned the small asteroid material that it collected in June 2010 to earth.
Ryugu has the shape of a roundabout with an average diameter of almost 900 meters. Its gravity field is a thousand times weaker than Earth's, so Hayabusa 2 can fly around the asteroid with minimal fuel.
Scientists classify Ryugu as a C-type asteroid, meaning that it is rich in carbon, the building block of organic molecules. Researchers seek to obtain unadulterated asteroid samples for analysis in laboratories, and to seek clues about the source of water and life on Earth.
The asteroid named in a famous Japanese fairy tale for a dragon palace concludes a circle with Ryugu the Sun every 1.3 years. His path leads him briefly into Earth orbit, making Ryugu a potentially dangerous asteroid.
While Hayabusa 2 is exploring Ryugu, NASA's OSIRIS-REx spacecraft is investigating another asteroid called Bennu – next year. Like Ryugu, Bennu is a carbon-rich asteroid that regularly traverses Earth orbit.
OSIRIS-REx will ship at least 60 grams (1.2 ounces) of Bennu samples in 2023, while Hayabusa 2 could return to Earth at least 100 milligrams of asteroid material. Scientists are confident that both missions will return with much more.
Tsuda said the engineers were not immediately sure how much sample Hayabusa 2 had collected on Thursday. However, officials are convinced that the projectile worked as expected, and Tsuda said he has the "highest expectation" that Hayabusa 2 will get a "decent amount of samples".
Teams from the Hayabusa 2 and OSIRIS-REx missions cooperate in their asteroid exploration efforts. JAXA and NASA have agreed to exchange asteroid specimens sent to Earth by Hayabusa 2 and OSIRIS-REx, and three US scientists from the OSIRIS REx team will be co-investigators of the Japanese mission. In return, three Japanese researchers formally joined the OSIRIS REx team.
On December 3, 2014, Hayabusa 2 launched a Japanese H-2A rocket and hit its asteroid target with ion engines that arrived near Ryugu last June.
The probe dropped off a pair of Japanese robots that hopped over Ryugu's surface in September, then launched a European mobile scout on the asteroid in October. The Miniaturlanders were the first mobile vehicles to explore the surface of an asteroid. All three robots returned image data and scientific data.
The mission managers hoped to get the first sample of Hayabusa 2 in late October, but the officials postponed the descent to conduct further analysis and surveys after the spacecraft had expected the asteroid to be rockier and more robust than expected. The managers decided to use a target marker at their preferred landing site for Hayabusa's first sampling attempt, which will help the spaceship navigate through a narrow corridor to a safe spot with no boulders, which could jeopardize the mission.
"Ryugu has turned out to be more difficult than expected, so we decided to use all available technologies," Tsuda said.
Hayabusa 2 could try to collect two more samples from other locations on Ryugu before leaving the asteroid in November or December. The spacecraft will have to travel to Earth by the end of the year to return home in December 2020 when Hayabusa 2 releases a sample carrier to re-enter the atmosphere and land in Australia.
Tsuda Intends to Quit Hayabusa 2's critical operations in the asteroid in June or July as Ryugu approaches the sun in its 1.3-year orbit.
In one of the sampling maneuvers, Hayabusa 2 will fire a copper plate – 400 times as massive as the tantalum bullet used on Thursday – to carve a crater on the asteroid, which will be the one on the asteroid Spacecraft snap material under the surface of Ryugu. The subsurface sample could be valuable to scientists because it did not expose material to the particles and radiation bombarding the asteroid's surface.
"We need to figure out what to do with the two planned touchdowns," Tsuda said
"At the moment, we can not formulate a timetable," Tsuda said. "We do not want to be inactive for a month. That's not our plan. The condition of the (spacecraft) is such that it is in top shape. Maybe every two or three weeks there are critical operations that we want to perform.
Takanao Saiki, Project Engineer and Flight Director of Hayabusa 2, said the release of the copper impactor to create a crater on Ryugu will be one of two key highlights of the mission.
"As big as the touchdown operation, and it's pretty risky," Saiki said Thursday. "To be honest (the impactor) is really a challenge, but all the team members have used their minds in touchdown to this day … We want to celebrate success today, but tomorrow we want to start preparing for (the impactor). "
" This has increased our momentum, but we must remain cautious, "said Saiki.
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