Rhea: Saturn's Second Largest Moon
8.06.2003

Rhea is the second largest moon of Saturn, behind Titan, and the largest without an atmosphere. It is composed mostly of water ice, but has a small rocky core. Rhea's rotation and orbit are locked together (just like Earth's Moon) so that one side always faces Saturn.

Regulus and the Red Planet
10.06.2010

Leo's royal star Regulus and red planet Mars appear in a colorful pairing just above the horizon in this starry skyscape. The photo was taken on June 4th from Oraman, a mountainous region of Kurdistan in western Iran near the border with Iraq.

Ecliptic New Zealand
10.07.2010

Four bright celestial beacons and a faint triangle of light follow the plane of the ecliptic as it arcs high through this southern hemisphere night skyscape. Seen on a July winter night from Lake...

Saturn: Light, Dark, and Strange
12.10.2010

What's creating those dark bands on Saturn? Sometimes it takes a little sleuthing to figure out the how and why of a picture taken by the Saturn-orbiting Cassini spacecraft. Let's see. That large orb on the left must be Saturn itself. Those arcs on the right are surely the rings.

Prometheus Rising Through Saturns F Ring
19.10.2010

What is that dark streak below Prometheus? Although it may look like a shadow or a trail blazed by sweeping up material, computer simulations indicate that the dark streak is better understood as an empty path pulled away by the gravity of Saturn's small moon.

Saturns Moons Dione and Titan from Cassini
20.04.2010

What would it be like to see a sky with many moons? Such is the sky above Saturn. When appearing close to each other, moons will show a similar phase. A view with...

Nashville Four Planet Skyline
9.02.2001

So far this February, evening skies have been blessed with a glorious Moon and three bright planets; Venus, Jupiter, and Saturn. But just last week, on January 30th, an extreme wide-angle lens allowed astrophotographer Larry Koehn to capture this twilight view of Moon and four planets

The Seasons of Saturn
2.07.2001

Soon it will be winter in Saturn's northern hemisphere. Since Saturn is tilted in its orbit around the Sun, it has seasons just like the Earth. When a hemisphere is tilted so that the Sun passes more directly overhead, summer occurs. Half an orbit later -- about 15 (Earth) years for Saturn -- winter occurs.

The Seasons of Saturn
5.04.2003

Since Saturn's axis is tilted as it orbits the Sun, Saturn has seasons, like those of planet Earth ... but Saturn's seasons last for over seven years. So what season is it on Saturn now? Orbiting the equator, the tilt of the rings of Saturn provides quite a graphic seasonal display.

Dark Terrain on Saturn s Iapetus
3.01.2006

Why are vast sections of Iapetus as dark as coal? No one knows for sure. Iapetus, the third largest moon of Saturn, was inspected again as the Saturn-orbiting robot Cassini spacecraft swooped past the enigmatic world again late last year.