Stars

The picture at left shows a Hubble Telescope view of an exploding star called Eta Carina. The gas and dust will eventually spread out to form a nebula (see Nebulae Section).
For most of recorded history the Earth was thought to be the center of the universe and never moved. The constellations were named and stories were told about them as they appeared through the seasons. Without a telescope or other aid the stars seem to be just points of light that move across the sky at night. Some wandered about which we now know are planets. Let's look at some facts about stars.
Stars can be packed so close as to be seen as Star Clouds, grouped like a ball as in Globular Clusters or rather loosely assembled in Open Clusters. Patterns are called Constellations and parts of these like the Big Dipper in Ursa Major are called Asterisms.
Stars come in different sizes. Supergiant stars range from 100 to 1000 times the diameter of the sun and giants range from 10 to 100 times the diameter of the sun. Dwarf stars can be 1000 times smaller than the sun. Click here to learn about our sun.

Stars vary in color based on their approximate surface temperature.

Color	Temperature	Example	Constellation
Blue-White	36,000° F and up	Rigel	Orion
White	20,000° F	Vega	Lyra
Yellow-white	11,000° F	Capella	Auriga
Orange	7,500° F	Arcturus	Bootes
Red	5,500° F	Antares	Scorpius

An example of a globular star cluster is at right in the constellation Hercules.
There are other types of stars, too. Double Stars are two stars that look like one to the naked eye but separate in a telescope view. They may not be orbiting each other as in a true Binary Star but appear to line up that way. In an Eclipsing Binary, stars orbit in such a way as to eclipse each other as seen from Earth. Variable Stars are stars that vary in brightness by various reasons. Novas and Supernovas are exploding stars that are blowing off their outer shells.
Two examples below show the Ring Nebula, a tube of gas and dust around a nova star and the Veil Nebula showing how the Ring might look after it expands and fades into the interstellar medium.

Ring Nebula	Veil Nebula