Nebulae

• A nebula is a cloud of dust, gas and plasma.

• The material clumps together to form larger masses that eventually are big enough to form a protostar.

• This is the first stage in the star life cycle.

• Nebulae often create star-forming regions, such as the Eagle Nebula.

Eagle Nebula – Pillars of Creation

Cat’s Eye Nebula

Ant Nebula

Crab Nebula

Protostar- a new star is born

Brown Dwarf• have a size between that of a giant planet like

Jupiter and that of a small star• any object 15 to 75 times the mass of Jupiter • called "failed stars"• all are parts of a binary system. (two stars orbit

around one another)• possible that brown dwarfs represent a lot of the

mass in the universe

Main Sequence Star (our sun)

Red Giant

• When a middle aged star begins to die, the temperature near the center rises.

• The star expands.• This will happen to

our sun in about 5 billion years.

• Once the red giant runs out of energy, it collapses and becomes a white dwarf, a small and dense star.

• A white dwarf is the center of the original star. It is very hot and cools down over the next billion years.

White Dwarf

- star near the end of its life

- was a red giant star that lost its outer atmosphere

Black Dwarf – a white dwarf that has cooled, lost its energy and no longer gives off light. It is a black object in space.

Giant Stars are more luminous than our sun and are 10 to 100 times larger in diameter than our sun.

Supergiant Stars are more luminous than giant stars and more than 100 times the diameter of our sun. They are

relatively cool stars.Betelgeuse is a supergiant star.

Supernova – collapse of the center of a red giant star produces a shock wave that blasts the star’s outer layers into space

Remains from a supernova

Neutron Star – the center left behind after a star’s supernova explosion

Pulsar – a neutron star that spins very fast and emits burst of radio waves

Black Hole

• An object with so much gravity and that is so dense, light cannot escape

• Most massive stars become black holes when they die

• Quasars are galaxies with black holes at their center. The Milky Way Galaxy is a quasar!

The life cycle of a star depends on its mass