Robotic spacecraft will fly to asteroid, comet

Probe plans to collect samples, explore celestial bodies during 10-year mission

Chinese scientists and engineers have begun to develop a robotic spacecraft to collect samples from an asteroid and have performed many ground tests, a top scientist said.

Ye Peijian, a leading spacecraft researcher at the China Academy of Space Technology, said Chinese researchers have chosen 2016 HO3, the smallest and closest "quasi-satellite" to Earth, as the target.

"We plan to use a probe to obtain some samples and bring them to Earth. After accomplishing this goal, it will continue to fly toward a main-belt comet to explore it," he told the main forum of the 2021 China Space Conference in Nanjing, Jiangsu province, on Saturday, which was China's Space Day. "The whole mission is expected to take about 10 years."

The mission's basic road map is to use a large carrier rocket to send a probe consisting of two parts－an orbiter and a reentry module－toward the asteroid. After approaching the asteroid, the spacecraft will first orbit around the small body and then fly very close to it to use a mechanical arm to collect samples from its surface. Carrying the samples, the probe will fly back to Earth orbit and release the reentry module, allowing it to fall back to the ground with the samples.

The orbiter will then travel toward a main-belt comet named 311P to continue its scientific exploration tasks.

Ye said the mission has been included in China's interplanetary exploration program, which also plans to retrieve samples from Mars and send a spacecraft to the Jovian system.

"We want to explore an asteroid because, scientifically speaking, such small, celestial bodies contain traces left through the evolution of our solar system that will help scientists deepen their knowledge about the system and origins of life," he said. "Exploring an asteroid requires new types of spacecraft and scientific apparatus, which will boost research in space science and technology."

Such missions will enable humanity to prospect for exploitable resources and devise methods for avoiding asteroid-caused hazards, Ye said.

Scientists have identified about 1 million asteroids in our solar system, with more than 20,000 of them traveling near Earth, he said.

2016 HO3, also known as 469219 Kamo'oalewa, was first spotted in April 2016 by an asteroid survey telescope at the Haleakala Observatory in Hawaii.

The celestial body travels in an orbit around the sun that makes it a constant companion of Earth. It is too distant to be considered a true satellite of Earth, but it is the best and most stable example to date of a near-Earth companion, or quasi-satellite, experts from NASA have said.

The mission will be challenging because it will take a very long period of time and involve a great many uncertainties, Ye said, adding that scientists hope it can obtain information about the physical, chemical, structural and orbital characteristics of 2016 HO3 and 311P.

He said that designers and engineers will need to develop technologies to allow the probe to carry out highly sophisticated maneuvers such as orbiting around a celestial body with weak gravitational attraction.