1. How Stars are created, How stars change, How stars die.
Star Life Cycle
How Stars are created,
How stars change,
How stars die.

4. Star Formation
If you look at the sky, you can see areas where stars are being born.
Stars are born in______________
The Orion Nebula (the fuzzy area in Orion’s sword) is giving birth to many stars.
Steps to star formation:
__________________ pulls gas and dust to centre of nebula.
Material becomes _____________.
____________ and ____________ increase.
__________________ begins and star “ignites” or is “born”.

5. Nuclear Fusion

7. Main Sequence Stars
Nuclear fusion squishes (fuses) hydrogen atoms together to make _________________ atoms.
A star does this for most of its life, and during this time it’s called a _________________________________________.
The star is constantly pulled together by __________________ but pushed apart by _______________________.
A star stays in main sequence as long as the push and pull are _____________________.

8. Main Sequence Stars
A star that is more _________________ (heavier) will…
Have more _________________________. And so it must
Burn hydrogen _______________ to keep balanced. And thus will
Have a higher ______________________ and will
Burn out _________________.

9. Red Giants
When a star runs out of ____________________, it goes to its next best fuel source and fuses ___________________.
Its outer layers grow outward, making it _______________.
Its outer layers get cooler, making it _______________.
The star is now a _________________________________ or a _________________________________.

10. The End of a Star’s Life Red Giant Red Supergiant
When all helium is used up, fusion _______________ and _______________ collapses the star to a white, glowing object that’s about the size of ____________________.
This is called a _______________________.
Over time, the star will slowly _______________.
When all helium is used up, fusion ________________, making all the elements up to __________.
When all fusable elements are used up, gravity collapses the star, creating a violent explosion called a ______________________.
The energy given off by the explosion allows fusion of atoms heavier than iron.
The leftover core becomes a _____________________ if small, or a ___________________ if big.