The global scientific community is keenly observing China’s launch of its Tianwen-2 probe, a dual-objective mission designed to explore a near-earth asteroid and a main-belt comet. The mission seeks to unlock secrets about the formation and evolution of our solar system.

According to Sara Webb, a Melbourne-based astrophysicist and lecturer at Swinburne University of Technology, “The Tianwen-2 launch marks an exciting milestone in our ongoing exploration of the solar system.” She added, “Every time we are able to return samples from solar system objects, we gain valuable insights into their formation and evolution.”

Tianwen-2 represents China’s first endeavor in asteroid sampling, focusing on the near-Earth object 2016HO3.Following sample collection and the dispatch of a return capsule to Earth, the spacecraft will journey to comet 311P, an “active asteroid” located in the asteroid belt between Mars and Jupiter.

richard de Grijs, a Sydney-based astrophysicist at Macquarie University, stated, “If successful, Tianwen-2 will make China the third nation to return asteroid samples to Earth, and the first to conduct a dual mission involving a comet.” He emphasized, “in this very way samples are rare at this time, any additional data will, without a doubt, offer significant new scientific insights, allowing us to better understand our place, origin and evolutionary history in the solar system.”

Unveiling Solar System Mysteries

De Grijs, also executive director of the International space Science institute-Beijing (ISSI-BJ), highlighted the mission’s broader scientific and technological importance. He noted the increasing meaning of detailed, in-situ studies of small rocky bodies in the inner solar system, even though the solar system’s inner planets have been explored for decades.

“China is on a realy fascinating solar system exploration trajectory,”

The selection of Tianwen-2’s targets adds scientific intrigue. Asteroid 2016HO3, with its unique orbit close to Earth, may provide clues to the early solar system. De Grijs suggests, “it might potentially be a fragment of the Moon that could have been dislodged by an earlier impact on the Moon.” Its orbit and composition could reveal information about lunar ejecta and the materials present during the solar system’s formation.

After dispatching the asteroid sample back to Earth, Tianwen-2 will proceed to comet 311P. unlike typical comets from the outer solar system, 311P resides in the main asteroid belt and exhibits unusual behavior, including multiple tails and episodic dust ejections.

Technological Advancements and International Collaboration

De Grijs explained, “Scientifically, a close-up look at this object will offer insights into how asteroids break up, the impact of solar radiation on asteroids and the nature of these active asteroids.”

He lauded Tianwen-2 as a significant technological advancement for China, building upon the success of Tianwen-1, which placed an orbiter, lander, and rover on Mars in may 2021. This achievement made China the second country to operate a rover on Mars.

the Tianwen missions, named after a classical Chinese poem, demonstrate China’s commitment to interplanetary exploration. De Grijs stated, “The mission will put China among the few nations (United States and Japan) capable of executing asteroid sample-return missions.” He added,”An innovation with respect to previous international missions is that it will continue to a second target,providing in-situ measurements. This is rare in a single mission.”

A key element of the mission is its attempt at deep-space anchored sampling, a complex operation involving a secure landing on a low-gravity body.

De Grijs believes Tianwen-2 showcases China’s strategic and steadily advancing exploration agenda. He remarked, “China is on a really interesting solar system exploration trajectory,” adding, “Each mission is designed to test certain key new capabilities and so far, this appears to have worked very well.”

He also emphasized the importance of international collaboration in space science. While Australia is relatively new to deep-space missions, it can contribute to the scientific analysis of mission data. De Grijs, actively fostering such cooperation through his leadership at ISSI-BJ, added, “As scientists, irrespective of where one comes from, global scientific collaboration benefits everyone involved.”