These raw, unprocessed images of Saturn's moon, Atlas, were taken on April 12, 2017, by NASA's Cassini spacecraft. The flyby had a close-approach distance of about 7,000 miles (11,000 kilometers).
These images are the closest ever taken of Atlas and will help to characterize its shape and geology. Atlas (19 miles, or 30 kilometers across) orbits Saturn just outside the A ring -- the outermost of the planet's bright, main rings.
Image Credit: NASA/JPL-Caltech/Space Science Institute
Explanation from: https://www.nasa.gov/feature/jpl/cassini-sees-flying-saucer-moon-atlas-up-close