PPolySim OS

Orbital Elements

A handful of numbers pin down any orbit in space. Adjust the size and shape and watch the satellite race through perigee and crawl through apogee.

Orbital ElementsLive

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An orbit's size and shape come from two numbers: the semi-major axis sets the period (and average altitude), and the eccentricity sets how elongated the ellipse is. Earth sits at one focus, so the satellite races through its low perigee and crawls at its high apogee — Kepler's second law in motion. The argument of periapsis rotates the ellipse.

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Data Inspector

Period166 min
Apogee alt.7629 km
Perigee alt.-371 km
Eccentricity0.40

Governing equation

Reading this result: Moderate eccentricity stretches the ellipse; the 166 min period is fixed by the semi-major axis alone, independent of how elongated the shape is.

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How it works

The Keplerian elements describe an orbit: the semi-major axis fixes its size and period, the eccentricity its elongation, and the argument of periapsis its orientation. Earth sits at one focus of the ellipse, so the satellite moves fastest at its low perigee and slowest at its high apogee — a live demonstration of Kepler's laws.

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Frequently asked questions

Is this orbital elements visualizer tool really free?
Yes. Orbital Elements runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.