Cislunar Space Beginner's Guide
From the Artemis program to planned lunar space stations, human spaceflight is moving from low Earth orbit into cislunar space. What is this 380,000-kilometre expanse? How do spacecraft fly through it? And how far along are the world's programs? This site answers those questions in plain, accurate language — no background required.
Start Here
Build the big picture in three steps, in order:
① What Is Cislunar Space
Concepts & territory — start here
② Cislunar Orbits
NRHO · DRO · transfer orbits explained
③ Research Frontiers
Directions · institutions · programs
From the News to the Knowledge
Just saw a launch headline and want the context? Space News is updated daily and archived by month — another way into this space. And whenever something is unclear, ask AI Q&A: it answers from this site's full content.
Glossary
Bilingual · searchable
Space News
Daily industry archive
AI Q&A
Ask anything across the site
Orbit Simulation
Tune orbits in your browser
Data & Code
Tools & resources
About This Site
Openly maintained on GitHub and Gitee under the Apache license. Contributions welcome.