Mission type | Asteroid
sample return Comet orbiter/lander |
---|---|
Operator | CNSA |
Mission duration | 10 years (planned) |
Spacecraft properties | |
Manufacturer | CAST |
Launch mass | ≤2,000 kg (4,400 lb) [1] |
Start of mission | |
Launch date | May 2025 (planned) [2] |
Rocket | Long March 3B [2] |
Launch site | Xichang [3] |
Contractor | CASC |
469219 Kamoʻoalewa orbiter | |
Sample mass | ≥100 g (0.2 lb) [1] |
311P/PANSTARRS orbiter | |
Orbital insertion | 2034 [4] [5] |
Tianwen-2 ( Chinese: 天问二号) is a planned Chinese asteroid sample return and comet exploration mission that is currently under development. [6] Tianwen-2 was originally known as ZhengHe. [7]
Tianwen-2 is scheduled to be launched on a Long March 3B rocket in May 2025. [2] It will use solar electric propulsion to explore the co-orbital near-Earth asteroid 469219 Kamoʻoalewa and the main-belt comet 311P/PANSTARRS. [8] [9] The spacecraft will rendezvous with Kamoʻoalewa and conduct remote sensing observations in orbit, before landing on the asteroid to collect a sample of 100 g (3.5 oz) of regolith. [1] [7] A nano-orbiter and nano-lander will be deployed to conduct remote sensing and sampling observations, and explosives will be used to expose potential subsurface volatiles for detection. [3]
The spacecraft will use both anchor-and-attach and touch-and-go methods to attempt collection of a sample from the asteroid. It would be the first time an anchor-and-attach method has been used on an asteroid, as both OSIRIS-REx and Hayabusa2 used touch-and-go. [10]
Tianwen-2 will then return to Earth to drop off a return capsule containing the sample and conduct a gravity assist maneuver to propel the spacecraft toward 311P/PANSTARRS. [11] A flyby of an unnamed asteroid may also be attempted en route to 311P/PANSTARRS. [3] Remote sensing and in-situ measurements will be conducted at 311P/PANSTARRS for at least one year. [7] [12]
The original name of this mission referenced the 15th century Ming Dynasty explorer Zheng He.
In 2018, a deep space exploration roadmap covering the 2020–2030 timeframe was proposed by researchers at the Chinese Academy of Sciences, [13] which included an asteroid exploration mission planned for launch around 2022 or 2024. [14] [15] In spring 2019, after a design study for the mission was carried out by the Chinese Academy of Space Technology (CAST), the CNSA began soliciting international proposals for scientific instruments to be carried on Tianwen-2. [7] [8] [11]
Tianwen-2 will incorporate several types of instruments, including wide/narrow angle multispectral and color cameras, a thermal emission spectrometer, a visible/near-infrared imaging spectrometer, a mass spectrometer, a magnetometer, and a charged/neutral particle and dust analyzer. [7] [11] International contributions to these payloads are being encouraged.