Approaching Jupiter
26.09.2000

In 1979 the Voyager 1 spacecraft compiled this view as it approached the gas giant Jupiter. Snapping a picture every time the Great Red Spot was properly aligned, the above time-lapse sequence shows not only spot rotation but also the swirling of neighboring clouds.

Earth, Clouds, Sky, Comet
3.04.1997

Does a comet's dust tail always orbit behind it? Since comets rotate, they shed gas and dust in all directions equally. Small ice and dust particles expelled by the comet, however, are literally pushed around by sunlight. The smaller the particle, the greater the effect.

This Comet Lovejoy
24.12.2014

Comet Lovejoy, C/2014 Q2, is framed like a cosmic Christmas tree with starry decorations in this colorful telescopic portrait, snapped on December 16th. Its lovely coma is tinted green by diatomic C2 gas fluorescing in sunlight.

A Solar Prominence from SOHO
9.11.2005

What happened to the Sun? Nothing very unusual: the strange-looking solar appendage on the lower left is actually just a spectacular looking version of a common solar prominence. A solar prominence is a cloud of solar gas held above the Sun's surface by the Sun's magnetic field.

A Wind From The Sun
17.02.1997

A wind from the Sun blows through our Solar System. The behaviour of comet tails as they flapped and waved in this interplanetary breeze gave astronomers the first hint of its existence. Streaming outward...

Arecibo: The Largest Telescope
9.03.1996

The Arecibo radio telescope is currently the largest single-dish telescope in the world. First opening in 1963, this 305 meter (1000 foot) radio telescope resides in a natural valley of Puerto Rico. The Arecibo...

Old Faithful Meets Hale-Bopp
26.05.1997

As Comet Hale-Bopp leaves our Northern Skies, it provides us with yet another burst of joy. On May 11th the fading comet was photographed behind the famous "Old Faithful" water geyser of Yellowstone National Park, Wyoming, USA, Planet Earth.

The Largest Rock Known
1.01.1998

There, that faint dot in the center - that's the largest rock known. It is larger than every known asteroid, moon, and comet nucleus. It is larger than any other rocky planet. (Nobody knows...

A Western Sky at Twilight
1.05.2004

On April 23rd, the Moon along with planets Saturn, Mars, and Venus (and planet Earth of course ...) were all visible in the west at twilight, captured here from a site near Saylorvillle Lake north of Des Moines, Iowa, USA.

Mercury Crosses a Quiet Sun
2.12.2019

What's that black dot crossing the Sun? The planet Mercury. Mercury usually passes over or under the Sun, as seen from Earth, but last month the Solar System's innermost planet appeared to go just about straight across the middle.