The Orion Nebula
Click on image for full size
NASA

Nebulae - The Dust of Stars

Why would we call nebulae stardust? Because the gas in nebulae is used to make new stars, and dying stars create nebulae from their gas. While stars are made of very hot, dense gas, the gas in nebulae is cool and spread out. Water is at least 1,000,000,000,000,000 times as dense as the gas found in nebulae.

Nebulae come in a variety of shapes. But their appearance is usually due to the type of energy source which is lighting them up. There is lot of gas that we can't see in the Galaxy. Something must happen for the nebulae to reveal themselves.

So, what happens to make nebulae glow? It depends on the type of nebulae. Some are involved in the formation of new stars. These are stellar nurseries called HII regions. The young stars found in HII regions are extremely hot and provide a lot of energy for lighting up nebulae. Some nebulae are created by dying stars: supernova remnants and the planetary nebulae surrounding white dwarfs.

Last modified January 13, 2006 by Travis Metcalfe.

You might also be interested in:

Exploratour - Evolution of the Solar System

The Sun and planets began as a cloud of gas, just like the one shown in this picture. The cloud was probably made of hydrogen and helium gas (the same gas which goes into a helium ballon which you can...more

Hubble Adds a New Dimension to Nebula

Scientists used the Hubble Space Telescope to look at the Ring Nebula (also known as M57). The nebula gets its name from its shape--it looks like a ring. The HST pictures show that the nebula is actually...more

For the Holidays...

This image of the NGC 2080 nebula was taken by NASA's Hubble Space Telescope. Because it is red and white and green, it looks like something that could be on front of a holiday card! The name of the nebula...more

Hubble's New Look

The pictures released by Hubble Space Telescope's new Advanced Camera for Surveys (ACS) are nothing but FAR OUT! This new camera was put on Hubble during a servicing mission in March 2002. As can be seen...more

Spiral Galaxie Collisions Occur More Often

Scientists are finding strong evidence thatspiral galaxies collide more often than once thought. It was once believed that one third of all the spiral galaxies have had a collision. However, a new camera...more

PAH

PAH is the short name for "Polycyclic aromatic hydrocarbons". Thank goodness this molecule has a short name! These are long strings of carbon atoms which form a ring. (That accounts for the "cyclic" and...more

Cassiopeia

Cassiopeia was the wife of King Cepheus. She was very pretty, and would often brag that she and her daughter were more beautiful than the sea nymphs, the Nereids. They complained to Poseidon, who sent...more

Draco the Dragon

Draco the dragon is a circumpolar constellation, which means it revolves around the North pole. It can be seen all year round. Draco is only present in the Northern Hemisphere, so those living in the...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA