Picture of the Day: Saturn's Rhea Eclipsed by the Larger Titan

563448main_PIA12515_full.jpg

Though it is Saturn's second-largest moon, Rhea appears tiny in this photograph of occultation, the celestial event in which a distant object is covered by a larger body. In the foreground of this image is Titan, the largest of Saturn's 62 known moons and the only natural satellite anywhere in our Solar System known to support a dense atmosphere.

"Occultations such as this one, in which one moon passes close to or in front of another, help scientists refine their understanding of the orbits of Saturn's moons," NASA explained. "Titan is about 621,000 miles (1 million kilometers) from Cassini in this image. Rhea is about 1.4 million miles (2.3 million kilometers) from Cassini."

To provide a better sense of the size of these moons, NASA noted that the image scale is nine miles per pixel for Rhea and four miles per pixel for Titan.

View more Pictures of the Day.

Image: NASA.

Presented by

Nicholas Jackson is a former associate editor at The Atlantic.

'How Do You Function Without a Cellphone?'

A short documentary about a San Francisco designer who doesn't own a cellphone, and a teenager who can't imagine life without hers.

Join the Discussion

After you comment, click Post. If you’re not already logged in you will be asked to log in or register with Disqus.

Please note that The Atlantic's account system is separate from our commenting system. To log in or register with The Atlantic, use the Sign In button at the top of every page.

blog comments powered by Disqus

Video

A History of Contraception

In the 16th century, men used linen condoms laced shut with ribbons.

Video

'A Music That Has No End'

In Spain, a flamenco guitarist hustles to make a modest living.

Video

What Fifty Shades Left Out

A straightforward guide to BDSM

More in Technology

Just In