Janus — moon orbiting Saturn, shown live in Cosmoscope, a real-time 3D map of the universe.
The larger of the co-orbital twins, waltzing with Epimetheus in a gravitational do-si-do that has repeated every four years for millions of years.
Cosmoscope puts Janus at its true position in the solar system, computed from JPL-derived ephemeris and updated continuously. Open the live 3D view to see, in real time, how far Janus is from the Sun and from Earth right now, how many minutes or hours light takes to cross that gap, and how fast it is moving along its orbit. Scrub the timeline to place Janus where it was on any past date, or where it will be years from now.