A Gravity Map of Earth
12.11.2001

Is gravity the same over the surface of the Earth? No -- it turns out that in some places you will feel slightly heavier than others. The above relief map shows in exaggerated highs and lows where the gravitational field of Earth is relatively strong and weak.

Ice Volcanoes on Mars
29.06.2001

What causes these unusual cone-shaped features on Mars? Spanning an average of only 100 meters at the base, these small cones appear near massive Martian volcanoes such as Olympus Mons. Near the cones are also dry channels and eroded banks.

A RADARSAT Map of Antarctica
15.11.1999

It's not easy to make a map of Antarctica. Earth's southern most continent is so cold and inhospitable that much of it remains unexplored. From space, though, it is possible to map this entire region by radar: by systematically noting how long it takes for radio waves to reflect off the terrain.

The Past of Asteroid Eros
9.10.2001

How did large rocks come to be scattered on the surface of asteroid Eros? Eros stands out not only because of its proximity to Earth but also because it was visited recently by NASA's NEAR-Shoemaker spacecraft.

A Total Eclipse of the Sun
10.03.1998

On February 26th, it was dark during the day. This total solar eclipse was the last visible from the Americas for this millennium. A total solar eclipse is exciting partly because it is so short.

Unusual Layers on Saturns Moon Phoebe
14.06.2004

What caused the unusual light and dark layers on Saturn's moon Phoebe? The layers were discovered just Friday during the Cassini spacecraft flyby of the small moon. Such layering is particularly evident on the crater just above the image center, where alternating light and dark material makes this crater appear particularly structured.

Storm Clouds Over Jupiter
26.11.1996

Storm clouds, similar to the familiar cumulonimbus thunderheads of Earth, appear to be present on Jupiter. The mosaic of images above shows the region near the raging edge of Jupiter's Great Red Spot, itself some 2 to 3 Earths wide, as observed by the Galileo spacecraft in June of this year.

The Crater Chain
15.07.1995

NASA's robot spaceprobe Voyager 1, took this closeup image of the surface of Jupiter's crater scarred moon Callisto in 1979. A mysterious chain of craters is seen to extend diagonally across the image (upper left to lower right). What could cause the craters to line up in such a regular fashion?

Spirit Rover at Engineering Flats on Mars
22.09.2004

Is it art? Here the paintbrush was the Spirit robotic rover, the canvas was the soil on Mars, and the artists were the scientists and engineers of the Mars Exploration Rover Mission. The picture...

In the Center of Saturns North Polar Vortex
4.12.2012

What's happening at the north pole of Saturn? A vortex of strange and complex swirling clouds. The center of this vortex was imaged in unprecedented detail last week by the robotic Cassini spacecraft orbiting Saturn. These clouds lie at the center of the unusual hexagonal cloud system that surrounds the north pole of Saturn.