Europa Rotating
16.01.2001

Evidence has been mounting that beneath the vast planes of ice that cover Europa lies water -- liquid oceans that might be home to alien life. The smallest of Jupiter's Galilean Moons (which include Io, Ganymede, and Callisto), Europa's deep interior is composed of mostly of silicate rock.

X-ray Moon and X-ray Star
27.02.1996

An X-ray star winks out behind the Moon in these before and after views of a lunar occultation of the galactic X-ray source designated GX5-1. The false color images were made using data...

Helios Helium
20.05.1996

Above is an image of the relatively quiet Sun made on May 18 in light emitted by ionized Helium atoms in the Solar chromosphere. Helium was first discovered in the Sun in 1868, its name fittingly derived from from the Greek word Helios, meaning Sun. Credit for the discovery goes to astronomer Joseph Lockyer.

The Radio Sky: Tuned to 408MHz
26.11.1996

Tune your radio telescope to 408MHz (408 million cycles per second) and check out the Radio Sky! You should find that frequency on your dial somewhere between US broadcast television channels 13 and 14.

Sojourner's View: The Sagan Memorial Station
10.07.1997

The robot rover Sojourner sees Mars from the perspective of a house cat. During the 7 month cruise to Mars aboard the Pathfinder spacecraft, Sojourner measured only seven inches tall in a stowed position but prowling the martian landscape it has stretched to its full height of 1 foot (30 centimeters).

X-Ray Pleiades
5.04.1998

The Pleiades star cluster is one of the jewels of the northern sky. To the unaided eye it appears as a lovely and tantalizing grouping of stars in the constellation of Taurus, while telescopic views reveal cluster stars surrounded by delicate blue wisps of dust-reflected starlight.

Aurora Oklahoma
13.11.2003

Nestled in the central US, the state of Oklahoma is noted for its gorgeous prairie skies and wide-open spaces, but not for frequent visitations of the northern lights. Still, following the intense solar activity...

The High Energy Crab Nebula
22.11.1998

This is the mess that is left when a star explodes. The Crab Nebula is so energetic that it glows in every kind of light known. Shown above are images of the Crab Nebula from visible light to the X-ray band.

Jupiter and the Moon s Shadowed Horizon
9.12.2004

Early Tuesday morning, December 7th, June Croft thought the southeastern sky above Atmore, Alabama, USA was beautiful. Watching the Moon rise through gossamer clouds, she noted, " ... the crescent Moon looked like it was held in the sky by a star just off its shadowed horizon." What was that star?

X-Ray Pleiades
28.08.1999

The Pleiades star cluster is one of the jewels of the northern sky. To the unaided eye it appears as an alluring group of stars in the constellation Taurus, while telescopic views reveal cluster stars surrounded by delicate blue wisps of dust-reflected starlight.