Sagittarius Star Cloud
20.05.2001

Stars come in all different colors. The color of a star indicates its surface temperature, an important property used to assign each star a spectral type. Most stars in the above Sagittarius Star Cloud are orange or red and relatively faint, as our Sun would appear.

Mercury: A Cratered Inferno
19.08.2001

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.

M51: The Center Of The Whirlpool
27.05.2000

In the center of M51, a spiral galaxy 23 million light-years away, astronomers have identified a dense region of young stars. Viewed face-on in the constellation Canes Venatici, the swirling arcs of this galaxy's spiral arms have inspired its popular name, The Whirlpool Galaxy.

Jupiters Rings Revealed
16.06.2002

Why does Jupiter have rings? Jupiter's rings were discovered in 1979 by the passing Voyager 1 spacecraft, but their origin was a mystery. Data from the Galileo spacecraft currently orbiting Jupiter later confirmed that these rings were created by meteoroid impacts on small nearby moons.

Painting with Solar Neutrons
25.10.1995

Solar flares are propelled high above the Sun's surface by powerful, twisted magnetic fields. The flares spew high energy atomic and subatomic particles into space. During an intense solar flare on June 15, 1991, a spray of solar neutrons was detected by the COMPTEL instrument onboard NASA's Compton Gamma Ray Observatory.

N159 and the Papillon Nebula
21.12.2003

In a search for massive stars, the Hubble Space Telescope has peered into yet another spectacular region of star formation. This nebula, known as N159, spans over 150 light-years and is located in the neighboring Large Magellanic Cloud galaxy, about 170,000 light years distant.

Infrared Trifid
13.01.2005

The Trifid Nebula, aka M20, is easy to find with a small telescope, a well known stop in the nebula rich constellation Sagittarius. But where visible light pictures show the nebula divided into three parts by dark, obscuring dust lanes, this penetrating infrared image reveals filaments of luminous gas and newborn stars.

The Fairy of Eagle Nebula
25.04.2005

The dust sculptures of the Eagle Nebula are evaporating. As powerful starlight whittles away these cool cosmic mountains, the statuesque pillars that remain might be imagined as mythical beasts. Pictured above is one of several striking dust pillars of the Eagle Nebula that might be described as a gigantic alien fairy.

Landsat 7 Views Planet Earth
14.05.1999

Launched last month, NASA's Landsat 7 spacecraft now orbits planet Earth. Looking down from an altitude of 700 km, Landsat 7 can map the planet's surface in visible and infrared bands and resolve features 30 meters across or smaller.

The Cosmic Infrared Background
6.02.2002

What cosmic wallpaper is on the sky? The answer depends on the type of light considered, and for some wavelengths, all the cluttering material in the foreground makes it still unknown. Recently, however...