Hot Gas and Dark Matter
4.04.1999

Is the gravity of the galaxies seen in this image high enough to contain the glowing hot gas? Superposed on an optical picture of a group of galaxies is an image taken in X-ray light.

Looking Down on Saturn
17.07.1996

This picture of Saturn could not have been taken from Earth. No Earth based picture could possibly view the night side of Saturn and the corresponding shadow cast across Saturn's rings. Since Earth is much closer to the Sun than Saturn, only the day side of the planet is visible from the Earth.

Apollo 12's Lunar Module Descends
7.10.1995

A few months after Apollo 11's historic Moon landing, Apollo 12 with commander Charles Conrad Jr., Command Module pilot Richard Gordan, and Lunar Module pilot Alan Bean returned for more geographic and scientific exploration.

The Sun Erupts
16.09.1996

The Sun is a seething ball of extremely hot gas. Above, the Sun was captured by Skylab in 1973 throwing off one the largest eruptive prominences in recorded history. The Sun has survived for about 5 billion years, and will likely survive for another 5 billion.

Ice Clouds over Mars
13.10.1997

Mars has clouds too. The above true color image taken in August by Mars Pathfinder shows clouds of ice high in the Martian atmosphere. Unlike Earth's atmosphere which is composed predominantly of nitrogen and oxygen, Mars' atmosphere is composed mostly of carbon dioxide.

Hot Gas and Dark Matter
2.09.1995

Is the gravity of the above galaxies high enough to contain the glowing hot gas? Superposed on an optical picture of a group of galaxies is an image taken in X-ray light. The X-ray...

Apollo 12 Visits Surveyor 3
24.11.1996

Apollo 12 was the second mission to land humans on the Moon. The landing site was picked to be near the location of Surveyor 3, a robot spacecraft that had landed on the moon three years earlier. Pictured above, Apollo 12 astronauts Conrad and Bean retrieve parts from the Surveyor.

The Sun Erupts
30.08.1998

The Sun is a seething ball of extremely hot gas. Above, the Sun was captured by Skylab in 1973 throwing off one the largest eruptive prominences in recorded history. The Sun has survived for about 5 billion years, and will likely survive for another 5 billion.

Water World
18.11.1995

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
23.12.1995

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.