Overview
Tiangong (天宫, "Heavenly Palace") is China's modular space station and the only crewed outpost in orbit besides the ISS. Assembled between 2021 and 2022 from three permanently docked modules, it has hosted rotating three-person crews continuously since June 2022. At roughly 100 tonnes it is about a quarter of the ISS's mass, but its laboratories support hundreds of experiments in microgravity science, astronomy and life sciences — and unlike the ISS, it is operated by a single nation. Track its position in real time on our live Tiangong tracker.
Station Layout
The Modules
Tianhe (core, April 2021) provides crew quarters, life support, propulsion and the robotic arm's home base. Wentian (July 2022) adds biology and life-science racks, a crew airlock and a backup control system; Mengtian (October 2022) carries fluid physics, materials and fundamental-physics experiments plus a cargo airlock for deploying small satellites. Full specifications for each are in our CSS modules guide.
Tiangong vs the ISS
| Tiangong | ISS | |
|---|---|---|
| Mass | ~100 t (station total) | ~420 t |
| Pressurised modules | 3 | 16 |
| Typical crew | 3 | 7 |
| Habitable volume | ~110 m³ | ~388 m³ |
| Altitude | 395 km | ~420 km |
| Inclination | 41.5° | 51.6° |
| First module | 2021 | 1998 |
| Operator | China (CMSA) | USA · Russia · ESA · Japan · Canada |
Compare their positions right now: the ISS tracker and Tiangong tracker both run live.
Assembly & Crew History
- Apr 2021 — Tianhe core module launched on a Long March 5B
- Jun 2021 — Shenzhou-12 delivers the first crew
- Jul 2022 — Wentian laboratory module docks
- Oct 2022 — Mengtian completes the T-configuration
- Nov 2022 → today — permanently crewed: Shenzhou rotations every ~6 months, Tianzhou cargo roughly twice a year — the full visiting-vehicle log runs live on the tracker and every launch is in our launch database
- Planned — the co-orbiting Xuntian space telescope (Hubble-class mirror, 300× field of view) and a possible expansion to six modules
Science Aboard
Tiangong's racks host 100+ concurrent experiments: protein crystallisation and stem-cell growth in Wentian, ultracold atomic clocks and fluid physics in Mengtian, plus external platforms exposing materials to raw space. China has opened payload slots to UN member states, flying experiments from over a dozen countries — its answer to the ISS's international role.
How to See Tiangong Tonight
Tiangong is the second-brightest artificial object in the night sky after the ISS, reaching magnitude −2 on a good pass — as bright as Jupiter, moving steadily without blinking. Passes last 2–6 minutes, best 1–2 hours after sunset or before sunrise. Get exact pass times for your location with the Tiangong pass predictor or our general pass predictions tool.