1. STARS A matter of life and death

2. The Star Story ESRT p 15: Characteristics of Stars
This chart uses tells the life cycle of stars
Most stars are what we consider main sequence (including our sun). They make up 90% of the stars in our sky.
Stars change into the other stages as they progress through their lives

3. Stars Stars are BIG balls of “burning” hydrogen gas
Hydrogen isn’t “burning” but going through nuclear fusion to make energy
Stars produce electromagnetic radiation (mostly light and heat)
As they deplete their hydrogen, stars go through different stages…

4. Stars Stars begin as clouds of gas and dust called NEBULA
PROTOSTARS develop from nebula
PROTOSTARS turn into STARS ONLY IF they are big enough!
If a star is born, it will be in the first stage…

5. Main Sequence Stars Make up 90% of the stars These are medium sized
Our sun is a main sequence star!
Stars stay in this part of their life cycle for the longest time
Main Sequence stars range in size, temperature, color and luminosity (brightness)
The Sun

6. Characteristics of Stars

7. Giant Stars The next stage after Main Sequence
They are times larger than our Sun
These are massive, red, cooler and brighter

8. Characteristics of Stars

9. Super Giants The next stage in a star’s life…
Up to 105 times bigger than our Sun!
They burn bright and die quickly
These stars tend to be HUGE and very BRIGHT but also relatively cool

10. Characteristics of Stars

11. White Dwarfs The last stage in a star’s life! 
These are smaller than our sun!
These are small, dim and HOT

12. Characteristics of Stars

13. Neutron Stars These are what’s left after a white dwarf “burns out”
These are what’s left at the end of the star’s life