Emission nebulae sometimes look like they have dark areas in them.

In many emission nebulae, an entire cluster of young stars is doing the work.

They can be seen as dark clouds against bright emission nebulae or background stars.

Sharpless 2-115 is another emission nebula with a complex pattern of light and dark patches.

This is an emission nebula showing glowing gas and darker dust lanes.

Usually the gases in an emission nebula are ionized.

An emission nebula is a cloud of plasma emitting light in many colors.

Because most of the universe is made of hydrogen, many emission nebulae appear red.

Emission nebulae are usually red because they usually produce red light.

Emission nebulae often have dark areas in them which result from clouds of dust which block the light.

Notably missing are pinkish emission nebulae indicative of new star birth.

N44 is classified as an emission nebula because it contains large regions of ionized hydrogen.

There are many types of emission nebula.

The star cluster is imbedded in the emission nebula IC 410.

Most emission nebulae are about 90% hydrogen, with the remainder helium, oxygen, nitrogen, and other elements.

IC 434 is a bright emission nebula in the constellation Orion.

It is very large emission nebula.

Emission nebulae make their own light.

Like all emission nebulae, its gas is ionization by a cluster of massive stars at its center.

The Gum catalog is an astronomical catalog of 84 emission nebulae in the southern sky.

For astrophotography, many photogenic targets (such as emission nebulae) are bright in the far red and near infrared.

The gaseous contortions of this emission nebula bear a resemblance to a pelican, giving rise to its name.

RCW 79 is an emission nebula in the constellation Centaurus.

It is classified as an emission nebula and as an H II region.

"This is an emission nebula.