Angular Sand on Martian Hills
24.10.2005

Why isn't this sand round? The robotic Spirit rover currently rolling across Mars has found notably angular sand in the Columbia Hills on Mars. Previously, small bits of sand found in the plains of Gusev Crater were significantly more round.

Galileo Demonstrates the Telescope
14.10.2001

Galileo Galilei made a good discovery great. Upon hearing at age 40 that a Dutch optician had invented a glass that made distant objects appear larger, Galileo crafted his own telescope and turned it toward the sky.

Uranus' Largest Moon: Titania
4.03.1996

Titania's tortured terrain is a mix of valleys and craters. NASA's interplanetary robot spacecraft Voyager 2 passed this moon of Uranus in 1986 and took the above photograph. The photograph was then transmitted back to earth by radio.

A Dust Devil on Mars
3.09.2002

Does the surface of Mars change? When inspecting yearly images of the Martian surface taken by the robot spacecraft Mars Global Surveyor currently orbiting Mars, sometimes new dark trails are visible. Although originally...

Aurora from Space
5.11.2005

From the ground, spectacular auroras seem to dance high above. But the International Space Station (ISS) orbits at nearly the same height as many auroras, sometimes passing over them, and sometimes right through them. Still, the auroral electron and proton streams pose no direct danger to the ISS.

Saturns Moon Epimetheus from the Cassini Spacecraft
11.02.2008

How did Epimetheus form? No one is yet sure. To help answer that question, this small moon has recently been imaged again in great detail by the robot spacecraft Cassini now orbiting Saturn. Epimetheus sometimes orbits Saturn in front of Janus, another small satellite, but sometimes behind.

April s Moon and the Pleiades
14.04.2005

After parting with the Sun late last week, April's moon graced the early evening sky. Its slender, three-day-old crescent shares this lovely telescopic skyview with the nearby Pleiades star cluster. Here, the Moon...

Mars: Shadow at Point Lake
5.02.2013

What if you saw your shadow on Mars and it wasn't human? Then you might be the robotic Curiosity rover currently exploring Mars. Curiosity landed in Gale Crater last August and has been busy looking for signs of ancient running water and clues that Mars could once have harbored life.

Earths Richat Structure
28.10.2002

What on Earth is that? The Richat Structure in the Sahara Desert of Mauritania is easily visible from space because it is nearly 50 kilometers across. Once thought to be an impact crater, the Richat Structure's flat middle and lack of shock-altered rock indicates otherwise.

Bonestell Panorama from Mars
20.01.2009

If you could stand on Mars -- what could you see? One memorable vista might be the above 360-degree panoramic image taken by the robotic Spirit rover over the last year. The above image involved over 200 exposures and was released as part of Spirit's five year anniversary of landing on the red planet.