Janus and Mimas

Saturn's moons Janus and Mimas coast in their silent orbits beyond the rings in this view from NASA's Cassini spacecraft. The ansa, or outer edge of the rings, is visible at left. Janus hangs above center, while Mimas shines at right. Owing to its irregular shape, Janus’ terminator – that line which separates day from night – is jagged, while Mimas’ smooth terminator belies its round shape and larger size.

The image was taken in green light with Cassini's narrow-angle camera on Oct. 27, 2015.

The view was acquired at a distance of approximately 598,000 miles (963,000 kilometers) from Janus and at a Sun-Janus-spacecraft, or phase, angle of 86 degrees. Image scale at Janus is 3.6 miles (5.8 kilometers) per pixel. The distance to Mimas was 680,000 miles (1.1 million kilometers) for an image scale of 4.1 miles (6.6 kilometer) per pixel.