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PolskiOrbital Mechanics Lab: Launch, Thrust & Trajectories (2D)
Launch a spacecraft into a Newtonian gravity well, fire prograde, retrograde and radial thrust burns, and read live apoapsis, periapsis, eccentricity and orbital period off an RK4-integrated two-body trajectory.
This 2D companion drives real Newtonian two-body physics instead of the 3D version's decorative rotating-cylinder scene: a central planet with adjustable gravitational parameter, a spacecraft launched at a chosen altitude and velocity, and an RK4 integrator that solves the same inverse-square gravity law that governs real orbits. Prograde and retrograde burns raise or lower the far side of the orbit, radial burns tilt it, and a live telemetry panel derives apoapsis, periapsis, eccentricity and orbital period directly from the spacecraft's instantaneous energy and angular momentum — the same vis-viva and orbital-elements formulas used in real mission planning — so you can watch a circular orbit become an ellipse, a hyperbolic escape trajectory, or a re-entry, purely from the numbers you set.
2D orbital-mechanics sandbox: RK4-integrated Newtonian two-body gravity, prograde/retrograde/radial thrust impulses that consume fuel, and live apoapsis/periapsis/eccentricity/period readouts computed from orbital energy and angular momentum.
2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install
Newtonian inverse-square gravity between the spacecraft and a fixed central planet, integrated with fourth-order Runge-Kutta (RK4) for numerical stability, even at high time-warp.
From the spacecraft's specific orbital energy and specific angular momentum at each instant — the same closed-form relation used to classify real orbits as circular, elliptical, parabolic or hyperbolic.
The periapsis drops below the planet's surface radius and the spacecraft crashes; burning too much prograde instead can push the orbit's energy above zero and send it on an escape trajectory.