1. Notes using the foldable
Life Cycle of a Star
Notes using the foldable

2. How long a star lives depends on the mass
Life Cycle of a Star
The smaller the stars, the longer the life because they use up their fuel more slowly
Nebula
Protostar
Main Sequence Stars
Red Dwarf
Yellow Star
Blue Giant
Red Super Giant
Red Giant
Supernova
White Dwarf
Black Dwarf
Black Hole
Neutron Star

3. Nebula All stars begin as parts of nebulas
A large cloud of gas and dust
large amount of gas in a small volume, very dense

4. Different Masses mean different types of stars
Protostar
The 1st stage of a star’s life
A contracting cloud of gas and dust
Pressure and heat start nuclear fusion
Different Masses mean different types of stars

5. Mass of star How long a star lives depends on how much mass it has
A small mass star uses less fuel so it lasts longer so . . .
The smaller the mass the longer it lasts

6. Main Sequence Stars
More than 90% of all stars are found in the main sequence.
In the main sequence, surface temperature increases as brightness increases.
Main sequence stars are stars that are fusing hydrogen atoms to form helium atoms in their cores.
These stars can range from about a tenth of the mass of the sun to up to 200 times as massive.

7. Red Dwarf
A small mass star
Can last up to 200 billion years

8. Yellow Star A medium mass star Our sun is a yellow star
Lives for 10 billion years

9. Blue Giant A large mass star 10-15 times larger than the sun VERY hot
Short lives because they have used up a lot of fuel

10. Red Giant The star runs out of fuel
outer parts expand, then the core shrinks
It turns red as it is cooling
This phase will last until the star exhausts its remaining fuel.
The pressure of the nuclear reaction is not strong enough to equalize the force of gravity so the star will collapse.

11. Red Super Giant The star runs out of fuel
The core shrinks and the outer parts expand
It turns red as it is cooling
This phase will last until the star exhausts its remaining fuel.
The pressure of the nuclear reaction is not strong enough to equalize the force of gravity so the star will collapse.

12. White Dwarf No more fuel left Faint glow from left over energy
Outer parts drift out into space
Small blue white hot core is left
About the size of Earth

13. Supernova As the core shrinks, pressure increases
Results in an explosion

14. Black Dwarf
When the white dwarf stops glowing it is dead\very dense

15. Black Hole Remains of explosion collapse into a black hole
Most large mass stars turn into black holes

16. Neutron Star After explosion some material left behind
Forms a neutron star
Dense and small

17. Life Cycle of a High-Mass Star
Life Cycle of a Low-Mass Star
Life Cycle of a High-Mass Star

18. Copy to the back of your foldable!