China's Tianwen-2 mission needs to overcome multiple technological challenges: scientists

China's first asteroid sample-return mission, Tianwen-2, launched on May 29 and set to explore two target asteroids, needs to overcome multiple key technological challenges, according to scientists.

The mission aims to achieve multiple goals over a decade-long expedition: collecting samples from near-Earth asteroid 2016HO3 and exploring main-belt comet 311P, which is farther from Earth than Mars.

The entire mission process for Tianwen-2 is complex. After launch, it will journey for about one year to reach its first target, during which it will perform deep-space maneuvers and mid-course corrections until it is about 30,000 km away from 2016HO3.

The probe will gradually approach the target, carrying out close exploration by circling and hovering over the asteroid to determine the sampling area, with a strategy of flying and probing simultaneously.

After completing the sampling, the spacecraft will fly back to the vicinity of Earth. A return capsule will separate from the main probe and is expected to deliver the samples to Earth by the end of 2027.

The main probe will then continue its voyage to rendezvous with the more distant target, the main-belt comet 311P, to carry out subsequent exploration tasks.

Multiple technological challenges are awaiting the exploration, including sampling on a low-gravity celestial surface, high-precision autonomous navigation and control, as well as trajectory design, according to the China National Space Administration (CNSA).

"We need to achieve a stable attachment and sampling of the asteroid in a near-zero gravity environment. The 2016HO3 asteroid has an average diameter of only about 41 meters and is spinning rapidly, which means we need to complete the stable attachment and sampling process within a limited time in a complex environment," said Han Siyuan, deputy director of the CNSA's Lunar Exploration and Space Engineering Center and spokesperson for the Tianwen-2 mission.

Asteroid 2016HO3 is located between 18 million km and 46 million km from Earth, while the main-belt comet 311P lies approximately 150 million km to 500 million km away.

The immense distance from Earth imposes stringent requirements on the probe's communication system, trajectory design, power management, and the capability to maintain highly reliable long-term operational performance, according to Han.

"During the exploration, we face larger issues such as delays in measurement and control signals, which will pose great challenges and raise the requirements to the probe's autonomous control, intelligence level, trajectory design and the durability and reliability of relevant products," said Han.

The mission's name originates from the long poem "Tianwen," meaning "Questions to Heaven," written by Qu Yuan (about 340-278 BC), one of the greatest poets of ancient China. The poem poses philosophical and cosmological queries about heaven, stars, myths, and nature, reflecting a spirit of seeking the truth.

CNSA noted that all of China's interplanetary missions bear the Tianwen series name, symbolizing the nation's enduring pursuit of truth and exploring nature and the universe. China's first Mars exploration mission was named Tianwen-1.

China's Tianwen-2 mission needs to overcome multiple technological challenges: scientists

The erroneous remarks made by Japanese Prime Minister Sanae Takaichi on China's Taiwan region have constantly drawn concerns and criticism from the international community.

At a Diet meeting last month, Takaichi claimed that the Chinese mainland's "use of force on Taiwan" could constitute a "survival-threatening situation" for Japan and implied the possibility of armed intervention in the Taiwan Strait.

Several international experts emphasized that these remarks interfere with China's internal affairs, posing a grave threat to the post-WWII international order and to regional peace and stability, and must be withdrawn immediately.

Speaking on Dec 13, the day that China observes as a National Memorial Day for Nanjing Massacre Victim, German scholar of international relations Eberhard Sandschneider suggested that Japan's failure to reconcile with its own history has allowed the way for the recent politically charged decisions that risk destabilizing regional diplomacy.

"We have had a very intensive debate about our own history here in Germany. And quite obviously, the same is not happening in Japan. And it is a part of the way you understand yourself in modern times, if you are not able to critically take into account what your country did in the past. It would be necessary. One should wish that Japan is making this step, but for the time being, unfortunately, I don't see any progress in this respect," he said.

Others have said Takaichi's remarks constitute a dangerous departure from international norms that challenge China's core sovereignty interests.

"I believe her remarks undermined the principle of the one-China policy, in terms of the position that China holds, and that, of course, amounts to interference. These actions are worrying. These actions risk taking the country back completely, and they are actions that should not be tolerated at all, because bringing back militarization is not something that should be encouraged, because it risks bringing war and also sending the very wrong signals about peace and stability and even governance of the country that is Japan itself," said Bernard Momanyi, editorial director of Capital FM, a news outlet in Kenya.

Int'l experts express concern over Takaichi's erroneous remarks