''Tianwen-2'' () is a Chinese asteroid sample return and comet exploration mission that launched on 28 May 2025. China National Space Agency (CNSA) plans for the probe to return samples from asteroid 469219 Kamoʻoalewa in 2027. After the mothership drops off the sample return vessel to Earth, it is planned that it will then rendezvous with

main-belt comet Active asteroids are Small Solar System body, small Solar System bodies that have asteroid-like orbits but show comet-like visual characteristics. That is, they show a Coma (cometary), coma, comet tail, tail, or other visual evidence of mass-loss ...

311P/PANSTARRS and explore it with its 11 onboard instruments.

Overview

CNSA launched the ''Tianwen-2'' probe using a

Long March 3B The Long March 3B (), also known as the CZ-3B and LM-3B, is a Chinese orbital launch vehicle. Introduced in 1996, it is launched from Launch Area 2 and 3 at the Xichang Satellite Launch Center in Sichuan. A three-stage rocket with four strap-on ...

carrier rocket on 28 May 2025 from the

Xichang Satellite Launch Center The Xichang Satellite Launch Center (XSLC), also known as the Xichang Space Center, is a spaceport in China. It is located in (), Mianning county, approximately northwest of Xichang, Liangshan Yi Autonomous Prefecture in Sichuan. It is op ...

in southwest China. The probe uses solar electric propulsion for maneuvering between its many objectives. It is planned to explore the co-orbital

near-Earth asteroid A near-Earth object (NEO) is any small Solar System body orbiting the Sun whose closest approach to the Sun (perihelion) is less than 1.3 times the Earth–Sun distance (astronomical unit, AU). This definition applies to the object's orbit aro ...

469219 Kamoʻoalewa and the

311P/PANSTARRS. The spacecraft will rendezvous with Kamoʻoalewa and conduct

remote sensing Remote sensing is the acquisition of information about an physical object, object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring inform ...

observations in orbit, before landing on the asteroid to collect a sample of of regolith. 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. 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 OSIRIS-REx was a NASA asteroid-study and sample-return mission that visited and collected samples from 101955 Bennu, a C-type asteroid, carbonaceous near-Earth object, near-Earth asteroid. The material, returned in September 2023, is expected ...

and '' Hayabusa2'' used touch-and-go. ''Tianwen-2'' will then return to Earth to drop off a return capsule containing the sample and conduct a

gravity assist A gravity assist, gravity assist maneuver, swing-by, or generally a gravitational slingshot in orbital mechanics, is a type of spaceflight flyby (spaceflight), flyby which makes use of the relative movement (e.g. orbit around the Sun) and gra ...

maneuver to propel the spacecraft toward 311P/PANSTARRS. A flyby of an unnamed asteroid may also be attempted en route to 311P/PANSTARRS. Remote sensing and in-situ measurements will be conducted at 311P/PANSTARRS for at least one year.

History

Hubble views extraordinary multi-tailed asteroid P2013 P5

In 2018, a deep space exploration roadmap covering the 2020–2030 timeframe was proposed by researchers at the

Chinese Academy of Sciences The Chinese Academy of Sciences (CAS; ) is the national academy for natural sciences and the highest consultancy for science and technology of the People's Republic of China. It is the world's largest research organization, with 106 research i ...

, which included an asteroid exploration mission planned for launch around 2022 or 2024.. Initially, the space probe was known as ''ZhengHe'', with the name referencing the 15th century

Ming Dynasty The Ming dynasty, officially the Great Ming, was an Dynasties of China, imperial dynasty of China that ruled from 1368 to 1644, following the collapse of the Mongol Empire, Mongol-led Yuan dynasty. The Ming was the last imperial dynasty of ...

explorer

Zheng He Zheng He (also romanized Cheng Ho; 1371–1433/1435) was a Chinese eunuch, admiral and diplomat from the early Ming dynasty, who is often regarded as the greatest admiral in History of China, Chinese history. Born into a Muslims, Muslim famil ...

. 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''.

Instruments

''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 Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a '' mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is us ...

, a

magnetometer A magnetometer is a device that measures magnetic field or magnetic dipole moment. Different types of magnetometers measure the direction, strength, or relative change of a magnetic field at a particular location. A compass is one such device, ...

, and a charged/neutral particle and dust analyzer. International contributions to these payloads are being encouraged.

Scientific payload

* Visible Infrared Imaging Spectrometer * Thermal Radiation Spectrometer * Multispectral Camera * Medium Field Color Camera * Detection Radar * Magnetometer * Charged and Neutral Particle Analyzers * Ejecta Analyzer * Narrow Field of View Navigation Sensor * Laser Integrated Navigation Sensor

Mission timeline

References

External links

{{Portal bar, Astronomy, Space, Spaceflight Chinese space probes Sample return missions 2025 in spaceflight 2025 in China Missions to comets Missions to near-Earth asteroids Proposed space probes