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rotastellar Orbital runtime
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Orbital Runtime · Simulation

Orbital Sim. Stateless orbital computation.

Propagate positions, detect eclipses, compute ground passes, and expand constellation templates - the digital twin every plan is built on. A stateless API at sim.rotastellar.com, no keys, no signup.

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Try it now

No keys, no signup. Send elements and a time.

sim.rotastellar.com
$ curl sim.rotastellar.com/v1/propagate -d '{
    "norad_id": "25544",
    "at": "2026-05-31T12:00:00Z"
  }'

# stateless · CORS-enabled · computed from orbital mechanics
{
  "position_km": [-4382.1, 5158.7, 100.4],
  "velocity_kms": [-1.9, -2.0, 7.4],
  "eclipse": false
}
Why stateless

Compute, don't cache.

Orbital state is a pure function of time and orbital elements - there's nothing to store and nothing to go stale. The sim service runs on the edge with no database: send elements and a timestamp, get back a physically-accurate answer, every time.

Propagation

Send elements and a time. Get the full state.

Stateless endpoints

Everything for an orbital digital twin.

POST /v1/propagatePosition and velocity for a satellite at a given time.
POST /v1/stateFull orbital state - illumination, eclipse, and geometry.
POST /v1/state/batchState for many satellites or many times in one call.
POST /v1/passesGround-station contact windows over an interval.
GET  /v1/templatesConstellation templates (Walker, sun-synchronous, and more).

Tracking, conjunctions, and ground-station geometry live on the intelligence API at api.rotastellar.com.

Architecture

At the edge, by design.

Stateless
No database, no cache. Every answer is computed from orbital mechanics on request.
Edge-native
Runs on Cloudflare Workers worldwide, so the digital twin is close to wherever you call it from.
Open
CORS-enabled, no API key. Call it from a browser, a notebook, or a flight planner.
Get started

Put your first workload in orbit.

Tell us what you want to run and the satellite you want to run it on. We'll come back with a feasible plan - or an honest reason it can't be done yet.

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