STAR LIFE CYCLE

From birth… to death…

Nebula

A huge cloud of dust and gas (mostly hydrogen) pulled together by gravity

Called the “birthplace of a star”

Theory is that the dust came from the explosions of other stars

Nebulae Examples…

Protostar

Gravity causes the particles of gas and dust to move together

Temperature and pressure increase and the cloud begins to spin

Star The protostar

continues to contract due to gravity

Temperature and pressure continue to increase

When temperature reaches 10 million degrees Celsius, nuclear fusion begins

Nuclear Fusion

At temperatures of 10 to 15 million degrees Celsius, nuclear fusion occurs in stars

Hydrogen are converted into one helium plus a lot of energy!

Main Sequence Stars(type of star depends upon mass)

Type Color Life Core Temp (C)

Red Dwarf

red 1 trillion years

10 million

Yellow Dwarf

Yellow / white

10 billion years

15 million

Blue Giant Blue / white

Millions of years

40 million

Main Sequence Stars

Death is determined by mass. When the last of helium atoms in the core are fused into carbon atoms, the star begins to die.

A sun-sized star will first expand to a red giant, then collapse on itself to become a white dwarf.

Star Death

Massive Star Death Energy is released

in a powerful explosion called a supernova

It then becomes a neutron star. No nuclear fusion is taking place to support the core, so it is swallowed by its own gravity.

Black Holes Only a very

massive star can become a black hole, which is not visible and is so dense nothing can escape.

Some media

http://science.discovery.com/video-topics/space-videos/supermassive-black-holes-the-black-hole.htm

http://www.space.com/15421-black-holes-facts-formation-discovery-sdcmp.html

The Visible Sun