Water World
17.11.1995

Water (Dihydrogen Oxide, H2O) is a truly remarkable chemical compound and is fundamental to life on Earth. Earth is the only planet in the Solar System where the surface temperature and pressure allow the three forms of water, solid (ice), liquid (ocean), and gas (water vapor condensing in clouds) to exist simultaneously on its surface.

Prometheus, Pandora and Saturn's F Ring
22.12.1995

The third and fourth innermost moons of Saturn were unexpectedly discovered to be gravitational "shepards." The inner moon Prometheus and the outer moon Pandora use their gravitational attraction to define Saturn's outermost ring.

A Flyby View of Ganymede
25.10.1996

This is what it would look like to fly over the surface of Jupiter's moon Ganymede. NASA's robot spacecraft Galileo recently approached only 6000 miles from this frozen ice-ball of a moon. The above image is a digital reconstruction from two images taken during this flyby.

Callisto: Dark Smashed Iceball
6.09.1995

Callisto is a dirty battered world, showing the most beaten surface of Jupiter's major moons. Made of a rocky core covered by fractured ice, Callisto's past collisions with large meteors are evident as large craters surrounded by concentric rings.

Introducing Comet Lee
27.04.1999

Another large snowball is falling toward the Sun. Comet Lee was discovered two weeks ago by Steve Lee (AAO) in Australia, and is expected to brighten as it approaches the inner Solar System. Comet...

Crescent Neptune and Triton
26.05.2023

Gliding through the outer Solar System, in 1989 the Voyager 2 spacecraft looked toward the Sun to find this view of most distant planet Neptune and its moon Triton together in a crescent phase. The elegant image of ice-giant planet and largest moon was taken from behind just after Voyager's closest approach.

Pillar at Sunset
5.03.2010

Reddened light from the setting Sun illuminates the cloud banks hugging this snowy, rugged terrain. Inspiring a moment of quiet contemplation, the sunset scene included a remarkable pillar of light that seemed to connect the clouds in the sky with the mountains below.

Aurora by Moonlight
11.02.2022

The ice was singing as light from a bright gibbous Moon cast shadows across this frozen lake, about 20 kilometers north of Stockholm, Sweden, planet Earth. In the alluring night skyscape captured on February 10, shimmering auroral curtains of light dance in the evening sky.

Rhea: Saturns Second Largest Moon
4.12.1999

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.

Nacreous Clouds over Sweden
9.01.2020

Vivid and lustrous, wafting iridescent waves of color filled this mountain and skyscape near Tanndalen, Sweden on January 3. Known as nacreous clouds or mother-of-pearl clouds, they are rare. This northern winter season they have been making unforgettable appearances at high latitudes, though.