Particle Sandbox is described as 'A two-dimensional gravity sandbox simulator' and is a Video Editor in the video & movies category. There are 2 alternatives to Particle Sandbox for Web-based. The best Particle Sandbox alternative is Super Planet Crash, which is free.
A game of gravity. Go crash some planets!
Make a planetary system of your own creation be stable (i.e. no planet is ejected, or collides with another body). This is of course exceedingly easy when your system comprises of a few Earth-mass planets, but dynamical instability can q.
Control the Sun with your mouse. Use it to manipulate the planets' paths. The Sun's pull gets stronger as planets get closer. If the gravity is at a right angle to the direction of travel, an orbit can form.
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