Press h to toggle orbit tracing (avoids lag) Click and drag (Will mess up rhythm) P to pause/unpause, R to reset. Arrow keys to change speed.
The planets travel at the same speed, but their distance from the sun affects their orbital period. A planet might make one full revolution in the time it takes another, more distant planet to make two. I made all the planets travel at the same speed to demonstrate this, with their orbit distances regular. Their orbital period ratios are as follows (from interior to exterior, measured in revolutions of the closest planet around the sun): 1:2:3:4:5