Triton: Neptune's Largest Moon
10.10.1996

Today marks the 150^th anniversary of the discovery of Triton. On October 10 1846, William Lassell was observing the newly discovered planet Neptune. He was attempting to confirm his observation, made just the previous week, that Neptune had a ring. But this time he discovered that Neptune had a satellite as well.

Mercury: A Cratered Inferno
30.11.1997

Mercury's surface looks similar to our Moon's. Each is heavily cratered and made of rock. Mercury's diameter is about 4800 km, while the Moon's is slightly less at about 3500 km (compared with about 12,700 km for the Earth). But Mercury is unique in many ways.

At the Edge of the Helix
22.04.1996

While exploring the inner edge of the Helix Nebula with the Hubble Space Telescope's Wide Field Planetary Camera 2, astronomers were able to produce this striking image - rich in details of an exotic environment.

Aurora and Orion
26.01.1997

Looking toward the south from low Earth orbit, the crew of the Space Shuttle Endeavor made this stunning time exposure of the Aurora Australis or southern lights in April of 1994. Aurora are visible at high northern latitudes as well, with the northern lights known as Aurora Borealis.

NGC 3242: The 'Ghost of Jupiter' Planetary Nebula
31.03.1997

It's a weed, it's Jupiter, no it's - actually planetary nebula NGC 3242. After a star like our Sun completes fusion in its core, it throws off its outer layers it a striking display called a planetary nebula.

Apollo 15: Driving on the Moon
7.06.1997

Apollo 15 astronaut James Irwin works on the first Lunar Roving Vehicle, before he and fellow astronaut David Scott take it out for a drive. Sloping up behind the lunar module "Falcon" on the left are lunar mountains Hadley Delta and Apennine Front, while about 5 kilometers behind Irwin is St. George Crater.

At the Edge of the Helix
20.07.1997

While exploring the inner edge of the Helix Nebula with the Hubble Space Telescope's Wide Field Planetary Camera 2, astronomers were able to produce this striking image - rich in details of an exotic environment.

3D View Of Jupiter's Clouds
30.10.1997

Every day is a cloudy day on Jupiter, the Solar System's reigning gas giant. This 3-dimensional visualization presents a simplified model view from between Jovian cloud decks based on imaging and spectral data recorded by the Galileo spacecraft. The separation between the cloud layers and the height variations have been exaggerated.

A Deep Field In The Southern Sky
2.12.1998

This new deep view of the cosmos is the sequel to the 1995 hit Hubble Space Telescope Deep Field. Billed as the Hubble Deep Field South, it was produced by pointing the space telescope toward a patch of sky in the southern constellation Tucana.

The First Explorer
12.08.2006

Inaugurating the era of space exploration for the US, the First Explorer, a thirty pound satellite, was launched into Earth orbit on February 1, 1958 by the Army Ballistic Missle Agency. Explorer I carried instruments to measure temperatures, micrometeorite impacts, and an experiment designed by James A.