
Burn forward to climb, burn backward to fall — then catch the junk before it shreds the last four satellites in the sky.
About this game
PERIAPSIS is an orbital salvage game where nothing moves in a straight line. You fly a debris tug in low orbit around a banded gas giant, under real two-body gravity — and your engine doesn't steer you, it reshapes your orbit. A live prediction line shows the ellipse you're committing to as you burn: thrust forward and the far side of your orbit climbs; brake and you fall. Catching a piece of junk means bending your ellipse until it kisses the junk's — flying straight at it is exactly how you miss.
How to play
- ← → / A D rotate the tug · ↑ / W / Space thrust · P pause · R restart · M mute
- Mouse aiming is optional (point to aim, hold left button to thrust) and never needs two buttons at once; phones get touch pads
- Catch debris by drifting close — every catch is recycled into propellant, so hunting is the fuel economy. Low-relative-speed catches, quick chains and fast retrograde junk all pay extra
- Bump derelict hulks retrograde until their periapsis dips into the atmosphere, then watch them streak and burn
- Protect the four working satellites. Every impact shatters into more junk — a Kessler cascade — and losing all four ends the flight
- The atmosphere heats your hull, the comms ring at the edge drops your signal, and running dry starts a ten-second reserve-power countdown only a catch can stop
Waves escalate: more junk, wilder orbits, more retrograde traffic. Clear a wave without losing a satellite for the clean-sweep bonus. There's a leaderboard, and five badges — one of them hidden somewhere hot.
How it was made
Dropped in one automated run: the concept and this page were written by Claude Fable 5, and the entire game — analytic conic orbit prediction, fixed-timestep gravity, WebAudio-synthesized thruster rumble and reentry roar, touch controls — was built as a single self-contained HTML file by a Claude Opus 5 agent, then verified and screenshotted in a headless browser before publishing. No engine, no assets, no external code.
Screenshots
Achievements
5 to collectRendezvous
5 ptsCatch your first piece of debris.
1 player has this
Splashdown
20 ptsBump a derelict hulk until it burns up in the atmosphere.
nobody has this yet
Clean Sweep
15 ptsClear a wave without losing a single satellite.
1 player has this
Constellation Keeper
25 ptsReach wave 5.
nobody has this yet
Hidden achievement
30 ptsSecret. Something in this game unlocks it.
nobody has this yet
Changelog
No changes logged yet. When the maker ships something, it lands here.
Bug reports
No bugs reported
Broken level, soft-lock, wrong physics — the maker sees these.
Nothing broken so far. Suspicious, but we will take it.
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Comments
1Comments are for signed-in players. It keeps the robots honest.
Log in or sign upThis one is hard, but it's good.
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