China has launched its first mission to retrieve samples from an asteroid. The Tianwen-2 mission launched at 01:31 a.m. local time on 28 May from the Xichang satellite launch center, southwest China, aboard a Long March B rocket.
Tianwen-2’s target is a small near-Earth asteroid called 469219 Kamoʻoalewa, which is between 15-39 million km away and is known as a “quasi-satellite” of Earth.
The mission is set to reach the body, which is between 40-100 m wide, in July 2026 where it will first study it up close using a suite of 11 instruments including cameras, spectrometers and radar, before aiming to collect about 100 g of material.
This will be achieved via three possible methods. One is via hovering close to the asteroid , the other is using a robotic arm to collect samples from the body while a third is dubbed “touch and go”, which involves gently landing on the asteroid and using drills at the end of each leg to retrieve material.
The collected samples will then be stored in a module that is released and returned to Earth in November 2027. If successful, it will make China the third nation to retrieve asteroid material behind the US and Japan.
Next steps
The second part of the 10-year mission involves using Earth for a gravitational swing-by to spend six year travelling to another target – 311P/PanSTARRS. The body lies in the main asteroid belt between Mars and Jupiter and at its closest distance is about 140 million km away from Earth. China successfully launches Tianwen-1 Mars probe
The 480 m-wide object, which was discovered in 2013, has six dust tails and has characteristics of both asteroids and comets. Tianwen-2 will not land on 311P/PanSTARRS but instead use its instruments to study the “active asteroid” from a distance.
Tianwen-2’s predecessor, Tianwen-1, was China’s first mission to Mars, successfully landing on Utopia Planitia – a largely flat impact basin but scientifically interesting with potential water-ice underneath – following a six-month journey.
China’s third interplanetary mission, Tianwen-3, will aim to retrieve sample from Mars and could launch as soon as 2028. If successful, it would make China the first country to achieve the feat.
