China has successfully launched its Tianwen-2 mission from the Xichang Satellite Launch Centre, aiming to retrieve samples from asteroid 469219 Kamo‘oalewa and later explore comet 311P/PANSTARRS, marking a major advancement in deep space exploration.
Key Objectives of Tianwen-2
- Asteroid Sample Collection from near-Earth asteroid Kamo‘oalewa (2016 HO3).
- Study of celestial origins and early solar system history.
- Technology Demonstration:
- “Touch-and-go” technique.
- “Anchor-and-attach” landing and sampling method.
- Planetary Defence Research:
- Understanding near-Earth object behavior.
- Future asteroid deflection capabilities.
- National Prestige:
- Reinforces China’s global space leadership alongside USA and Japan.
Target Asteroid: 469219 Kamo‘oalewa
- Discovered: 2016 (Pan-STARRS 1 Telescope, Hawaii).
- Type: Quasi-satellite (orbits Sun but stays near Earth).
- Distance: 15 to 39 million km from Earth.
- Size: Estimated 40 to 100 meters.
- Unique Trait: Its light spectrum resembles lunar rock, suggesting it may be a fragment of the Moon.
- Scientific Value: Rare orbit, unknown origin, and proximity to Earth.
Sampling Technique
- The spacecraft will:
- Hover and Probe: Hover near the asteroid. Extend a robotic arm for surface analysis.
- Rotating Brushes + Gas Jet: Use rotating brushes and gas blowers to collect particles. Collect surface fragments and funnel into container.
- Anchor-and-Attach: Possibly attempt “anchor-and-attach” landing using three legs to stabilize; A claw to grip the surface; A collector to gather materials. Necessary due to extremely low gravity of asteroid.
- Challenges:
- Extremely low gravity on asteroid surface makes landing and sampling difficult.
Comparisons with Other Missions:
| Country | Mission | Year | Object | Technique |
| Japan | Hayabusa | 2010 | Itokawa | Touch-and-go |
| Japan | Hayabusa2 | 2019 | Ryugu | Touch-and-go |
| USA | OSIRIS-REx | 2020 | Bennu | Touch-and-go |
| China | Tianwen-2 | 2025-2027 | Kamo‘oalewa | Touch-and-go + Anchor |
Second Phase of Mission (2027–2035)
- After returning asteroid samples in 2027, Tianwen-2 will use Earth’s gravity slingshot to visit comet 311P/PANSTARRS by 2035.
- 311P is a hybrid object (shows both comet-like and asteroid-like activity).
- Instruments on board: Cameras, spectrometers, particle analysers, radar, and magnetometer.
- Purpose: Understand the transition between asteroids and comets, and study the
China’s Broader Space Vision:
- Vision: Establish China as a global space superpower by mid-21st century.
| Mission | Focus | Status |
| Tianwen-1 | Mars orbiter + rover mission; Successful Mars mission. | Completed |
| Tianwen-2 | Asteroid + comet sample return; | Launched |
| Tianwen-3 | Mars sample return (future); Upcoming Mars sample return mission. | Planned |
| Tianwen-4 | Exploration of Jupiter & Uranus; Planned mission to Jupiter system and Uranus. | Planned |
- Long-term Goal: Establish China as a leading space power by mid-21st century.
Strategic Importance
- Scientific: Insights into solar system formation, Moon-Earth relationship, and origin of water. Explore the formation and evolution of quasi-satellites.
- Technological: Advances in landing, robotic sampling, and multi-object deep space navigation.
- Diplomatic: Positions China as a major competitor to NASA, JAXA in space science. Asserts China’s leadership in space science and innovation.
- Planetary Defence: Enhances knowledge of near-Earth object (NEOs) dynamics for future risk mitigation and to aid asteroid deflection research.
- Technology Testing: Combines both “touch-and-go” and “anchor-and-attach” sample collection methods.
Relevance for India and Global Space Community
- Sets a benchmark in asteroid sample retrieval and deep space navigation.
- Strengthens competition and cooperation possibilities in international space research.
- Opens up comparative opportunities for ISRO and other global agencies to develop similar capabilities.