Positions are exact on the day Sputnik launched (from the JPL calculator) and then diverge; I use a series expansion to approximate the solution to [Kepler's][kepler] formulation for position as a function of time that's accurate to a couple of hundredths of radians (OK for animation.)
The rings are accurate (alpha is set to their albedo plus a small constant that makes Jupiter's and Uranus's rings visible).
Use the vertical slider to change perspective, the top left slider to move in time, and the top right one to scale the planets' radii relative to the sun. The date range is from [first flight][ff] to first contact ...