Iapetus

Iapetus — moon orbiting Saturn, shown live in Cosmoscope, a real-time 3D map of the universe.

The yin-yang moon: one side black as soot, the other white as snow, with a mountain ridge circling its equator like a walnut seam.

Radius
734.5 km
Orbit
3,561k km from Saturn
Period
79.33 days
Two faces
One hemisphere coal-dark, the other bright ice
Ridge
A 13-km-high wall around its equator

Seeing Iapetus in real time

Cosmoscope puts Iapetus 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 Iapetus 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 Iapetus where it was on any past date, or where it will be years from now.

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