Planetary Orbit Simulator — astro.dev.id

Planetary Orbit Simulator

Orbit Settings

set parameters for:

semimajor axis (AU) 1.00

eccentricity 0.400

Animation Controls

animation rate (yrs/s) 0.20

show empty focus show semiminor axis show center show semimajor axis r₁ — line to sun r₂ — empty focus

\(r_1 + r_2 = 2\,a\)

sweep continuously

sweep size 1 / 16 (6.3%)

\(dA/dt = \text{const}\) — equal areas in equal times

sweep duration — yr swept area — AU² time since perihelion — yr

\(P^2 = a^3\)

linear logarithmic

\(v\) = — km/s	vec	line
\(a\) = — m/s²	vec	line
angle between vectors: —

Visualization Options

show solar system orbits show solar system planets label the solar system orbits show grid

Help

This simulator models the motion of a hypothetical planet that orbits the sun according to Kepler's laws of motion.

The size and eccentricity of the planet's orbit can be set using the sliders in the Orbit Settings panel. Presets for the existing planets can be loaded by selecting a planet from the combo box and clicking OK.

Since the planets take months to years to orbit the sun the animation is shown speeded up. You can control the animation rate in the Animation Controls panel. The rate is specified in simulated years per second.

The Visualization Options panel provides options for showing the solar system planets and their orbits. Note that all of the planets' orbits are shown pointing in the same direction. In reality this is not the case (nor are the planets in exactly the same plane).

The clear optional features button hides the solar system planets and resets the features selected in the tabbed panel.

The tabbed panel beneath the visualization lets you control options specific to each of Kepler's laws. The Newtonian Features tab lets you see the velocity and acceleration vectors of the planet.

The orbit visualization window is partially interactive. The planet's position in the diagram can be adjusted by dragging it around.

About

The Planetary Orbit Simulator demonstrates Kepler's three laws of planetary motion using real orbital mechanics.

Orbital positions are computed by solving Kepler's Equation (M = E − e·sin E) via Newton-Raphson iteration, giving accurate positions at any point in time.

Physical quantities (velocity, acceleration) are derived from the vis-viva equation and Newton's law of gravitation.

Built with HTML5 Canvas and vanilla JavaScript. Part of the astro.dev.id simulation suite.