Nebulae

Bright nebula are clouds of interstellar gas and dust that glow with light emitted by the gas (emission nebulae) or by reflected starlight (reflection nebulae) or both. Dark nebulae consist of clouds of gas and dust that are not illuminated and appear as dark areas against a brighter background.

NGC6888, the Crescent Nebula, is an arc of gas ejected from a Wolf-Rayet star, one of the hottest of all stars. The leading edge of this gas cloud is hurtling through space at nearly 2000 miles per second.

The Dumbbell Nebula (M27) in Vulpecula is classified as a planetary nebula. In small telescopes, the brighter regions in this object give it an hourglass shape.

The Horsehead Nebula in Orion is a dark nebula that partially blocks our view of the bright emission nebula in the background.

M42, the Orion Nebula, is one of the most active star-birth regions known. This huge cloud of gas and dust is several light years across. It is lit up from radiant energy streaming out of the four bright central stars which were born out of the cloud only about one million years ago.

M17, the Omega Nebula, is a huge molecular cloud where massive star formation is taking place. An emission nebula. this glowing gas is predominantly ionized hydrogen.

M16, the Eagle Nebula, is another emission nebula that is famous as a star "nursery". The Hubble Space Telescope has taken some fantastic images of this region, showing new star birth.

M57, the Ring Nebula, is an example of a planetary nebula. The expanding cloud of gas has been ejected by the white dwarf star in the center.