Where research code doesn't just run in CI — it runs in orbit.
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Bring your research to orbit — we'll handle the rocket. 🛰️
Tiansuan Constellation (天算星座 — literally "celestial computing") is an open-source testbed of low-Earth-orbit satellites for computing and networking research. It was initiated in 2021 by Prof. Shangguang Wang's team at the State Key Laboratory of Networking and Switching Technology, Beijing University of Posts and Telecommunications (BUPT), and is jointly built with partners across industry, academia, and research.
Putting an experiment into orbit has always demanded a launch budget, a hardware program, and a healthy tolerance for risk — which is why most research ideas never leave the ground. Tiansuan exists to change that. The constellation pairs in-orbit satellites with ground stations, a cloud supercomputing center, and an open service platform, so that the global research community can deploy, test, and measure real systems on real satellites — openly, and at low cost.
Beyond the satellites themselves, the team founded OPENSAT — Open Source Satellite Community, an open community that gathers satellite-related open resources — software, papers, datasets, and industry standards and specifications — from Tiansuan and from the wider community.
At a glance: 5 satellites in orbit · 7 world-first systems verified on orbit · 33 alliance members across China and Europe · 20+ peer-reviewed publications (2021–2025)
| Phase | Scale | Status |
|---|---|---|
| Phase I | 6 LEO satellites (2 main · 2 auxiliary · 2 edge) + ground stations, TT&C center, cloud supercomputing center, open service platform | ✅ In service — 5 of 6 satellites on orbit |
| Phase II | 24 satellites | In planning |
| Phase III | 300 satellites | Long-term vision |
Where we are heading next:
- Batch-deploying payloads verified on pilot satellites across the growing fleet
- Cloud-native satellites with inter-satellite links, plus cloud-native ground stations
- An autonomous, controllable, software–hardware co-designed open-source satellite platform
Once completed, the constellation will stand as a global base for satellite-network innovation — one of the forces shaping the coming era of interstellar exploration.
Phase I of the constellation comprises 6 LEO satellites — 2 main, 2 auxiliary, and 2 edge satellites — supported by ground stations, a TT&C center, a cloud supercomputing center, and an open service platform. Five are flying today.
| Satellite | Launched | Role in the constellation | What it carries / proves |
|---|---|---|---|
| Tiansuan-1 · "Baoyun" (宝酝号) | Dec 7, 2021 | Pilot satellite: intelligent service & computing platform | On-orbit 5G soft base station + lightweight core network, 6G cognitive service architecture, KubeEdge + Sedna edge-AI stack, spaceborne UPF, DOIP protocol, and the first satellite-borne Data-Internet test node. Built with China Mobile Research Institute, Peking University, and Huawei Cloud |
| Tiansuan-2 · "Chuangxing Leishen" (创星雷神号) | Feb 27, 2022 (record 22-satellite rideshare) | Pilot satellite: satellite–ground integrated network services | KubeEdge-based remote-sensing inference, lightweight 5G core network v2, QUIC on orbit, and an adaptive service-provisioning framework for satellite edge computing. Built with Beijing University of Technology |
| Tiansuan-3 · "Wangqizhou" (望齐州号) | Dec 14, 2022 — launch failure | Edge satellite | Payload lost during launch; its role will be taken over by satellites in later phases |
| BUPT-1 (北邮一号) | Jan 15, 2023 | First main satellite: core node of the open-source in-orbit testbed | Cloud-native satellite running distributed on-orbit AI inference, 5G core network v4, and eBPF-based lightweight network elements; hosted Tsinghua's IoTDB, Peking University's Data-Internet node #3, Beihang's lightweight containers, and the Ascend Atlas 200 AI acceleration module |
| BUPT-2 (北邮二号) | May 17, 2025 | High-compute core node | A self-developed high-performance server flying as the computing payload — a major step up in on-orbit compute for "process-then-downlink" satellite autonomy. Runs on-orbit container updates, WASM measurements, semantic image communication, model compression and incremental learning, and single-event-upset characterization. Hosted ZTE's spaceborne core-network service trials |
| BUPT-3 (北邮三号) | May 17, 2025 | Inter-satellite interconnection node | High-bandwidth laser inter-satellite links, breaking the bandwidth, latency, and security bottlenecks of conventional microwave links — the foundation of a space-based information highway |
The constellation's work also lives in OPENSAT — Open Source Satellite Community, an open satellite community founded by the Tiansuan Constellation team. OPENSAT shares satellite-related open resources — software, papers, datasets, and industry standards and specifications — from the Tiansuan team and from the wider community, giving anyone a single place to find, reuse, and contribute to them.
The following is a selection of the constellation's open-source projects:
| Project | What it is |
|---|---|
| TiansuanExperimentPlatform | 🚀 The heart of the constellation: apply to run your experiment on our real satellites — open to the global academic community, low-cost and easy to access |
| RROS | 🦀 A dual-kernel OS for satellites — Rust RTOS + Linux — for scenarios needing both real-time and general-purpose abilities; the first Rust OS to run in orbit |
| MobiCom24-SatelliteCOTS | Artifact of Deciphering the Enigma of Satellite Computing with COTS Devices (ACM MobiCom '24) |
| SatLink-Artifact | Measurement and analysis of LEO satellite data transmission: performance and reliability |
| ATC25-RHONE-DATA | Emulating space computing networks with RHONE (USENIX ATC '25) |
| awesome-satellite-data | A curated collection of satellite data for scientific research |
The constellation is open — and it needs you.
🚀 Run your experiment in orbit. The Tiansuan Experiment Platform lets researchers worldwide propose experiments, submit their code, and have our team deploy it on real satellites — then return your results and data. No launch vehicle required. Start with the User Agreement.
💻 Contribute code. We build in the open: satellite OS kernels (RROS) and satellite open-source community (OPENSAT). All code is public, and contributions are welcome.
📊 Use our data and artifacts. Measurement datasets (SatLink), emulation tools (RHONE), and paper artifacts are all public. Use them, extend them, and cite the papers — that's what they're for.
- 🌐 Website: http://www.tiansuan.org.cn (English · 中文)
- 🧪 Experiment platform: platform repository
- 📧 General:
buptts@163.com· Alliance applications:liyuanzhe@bupt.edu.cn - 🛰️ Maintained by the Star Network and Intelligent Computing Laboratory, BUPT
Founded at BUPT · Co-built with Spacety and the Tiansuan Alliance