A star is a huge ball or disk of plasma that is primarily held together by gravity. On a clear night on Earth, we are able to see a lot of Stars. We can see 3000 stars on a typical night with the un-aided eye. The closest Star to Earth, is the Sun. Which is the main energy source for us.

The most visible stars on the celestial sphere were grouped together into constellations. The most brigthest Stars were also given names.

For the majority of a Star's life, it shines very brightly because of thermonuclear fusion in its core. Which is then radiated into outer-space.

A star begins as a dying or collapsing cloud. The cloud is composed of helium, helium, and other heavy elements. After the cloud's core, is very dense. Then some of the Hydrogen is converted into Helium. Which is a process known as nuclear fusion.

There are 18 different types of Stars and groups. Binary Stars, Black Dwarfs, Black Holes, Brown Dwarfs, Galaxies, Main-Sequence Stars, Nebulas, Neutron Stars, Novas, Pulsars, Quasars, Red Giants, Star Colours, Supergiants, Supernovas, Variable Stars, White Dwarf, and a Wolf-Rayet Star.

Astronomer's determine the mass, and age of a Star by viewing a Star's spectrum, luminosity, and it's motion through space. The mass of a Star determines it's future.

To get to our nearest Star (or closest to The Sun) it would take us approximately 118, 000 years!

After a Star runs out of hydrogen to fuse into Helium. Then the Star dies. A Star can die in several different ways, depending on it's type.