China is ready to launch a mission to collect samples from a near-Earth asteroid.
Propellant was being loaded into a Long March 3B rocket at Xichang spaceport in the southwest of the country, following checks and rehearsals, the China National Space Administration (CNSA) announced on May 26.
The Tianwen 2 mission is set to launch on May 29 Beijing time, according to CNSA. This aligns with airspace closure notices suggesting that launch will take place around 1:30 p.m. EDT on May 28 (1730 GMT; or 1:30 a.m. Beijing time, May 29). It was unclear at time of reporting if live streams of the event would be available.
“At present, at the Xichang Satellite Launch Center, various preparations for the mission are progressing steadily. The Long March 3B Y110 carrier rocket that will carry out the launch is about to be filled with propellant,” the CNSA statement read.
Tianwen 2 will first target Kamo’oalewa (also referred to as 2016 HO3), a small, unusual near-Earth asteroid, aiming to deliver samples of the object to Earth sometime in 2027. The mission will test out a number of sampling techniques, including attempting a landing on the rocky body, if terrain allows.
Scientists want to assess the samples to determine the origins of the asteroid, which may be pieces of the moon sent into orbit by a giant impact, and provide insights into the wider evolution of the solar system. Mission data could also assist planetary defense planning.
Kamo’oalewa is just the first of the mission’s destinations, however. Tianwen 2 will use its return visit to Earth to both drop off the samples in a reentry module and use our planet’s gravity to slingshot it on a path that will take it to the comet 311P/PANSTARRS, arriving around 2035.
Once there, Tianwen 2 will orbit the comet and use its range of cameras, spectrometers and other instruments to collect data that may provide insights into mysteries such as where Earth’s water came from. The spacecraft also carries charged and neutral particle analyzers, a radar instrument, an ejecta analyzer and a magnetometer.
311P orbits in the main asteroid belt between Mars and Jupiter, exhibiting the orbit of an asteroid but also displaying dust tails like a comet, according to Chinese researchers.
Tianwen 2 is China’s second planetary exploration mission, following on from the Tianwen 1 Mars orbiter and rover, which launched in 2020. Tianwen 3 will be a Mars sample return mission, launching in late 2028, while Tianwen 4 will visit the Jupiter system and potentially Uranus.
