http://aspire.cosmic-ray.org/Labs/StarLife/starlife_equilibrium.html
Page 1
A) What are the four basic stages in the life cycle of a star?
1) ________________ 2) _________________
3) ________________ 4) _________________
B) Where are stars born? Describe a nebula.
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Page 2: Protostars
C) Watch the protostar animation. Describe the three steps of how a star begins to form.
1) ___________________________________________________________________________________
2) ___________________________________________________________________________________
3) ___________________________________________________________________________________
D) A nebula consist of _______ % Hydrogen and _________ % Helium.
E) Watch each stage of the equilibrium video. Write the six steps needed to reach equilibrium.
1) ___________________________________________________________________________________
2) ___________________________________________________________________________________
3) ___________________________________________________________________________________
4) ___________________________________________________________________________________
5) ___________________________________________________________________________________
6) ___________________________________________________________________________________
What is the difference between a brown dwarf and a protostar?
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Page 3: Stars:
F) Interactiv lab-
Complete the beginning of their life cycles lab and place your answers for each stage below.
Small:
Does this star reach main sequence? Y N
If yes, how long was the main sequence?_______________ low:
Does this star reach main sequence? Y N
If yes, how long was the main sequence?_______________ medium:
Does this star reach main sequence? Y N
If yes, how long was the main sequence?_______________ massive:
Does this star reach main sequence? Y N
If yes, how long was the main sequence?_______________
G) Choose a hypothesis regarding the length of a star’s life and write a 2-3 sentence explanation for your choice.
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Page 4: Stars
G)Equilibrium – main Sequence lab
Stage 1 pressure
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˅ gravity
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Temperature
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Stage 2
Stage 3 pressure
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˅ pressure
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˅ gravity
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Temperature
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Temperature
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Stage 4
Stage 5
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Temperature
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H) Equilibrium Quiz _ True or false
1) _____The strength of gravity changes throughout the for equilibrium in a star.
2) _____ When temperature increases, gravity decreases.
3) _____ When temperature increases, gas pressure increases.
4) _____ When gas pressure equals gravity, the star is at equilibrium.
Hydrogen Burning ( Stable Star Life)
Detailed reaction for Hydrogen burning in stars:
Write the six steps for the hydrogen fusion reactions that occur.
1) ____________________________________
2) ____________________________________
3) ____________________________________
4) ____________________________________
5) ____________________________________
6) ____________________________________
Quiz
1) When the star is out of hydrogen fuel, what will happen to the temperature at the core?
A. Increase B. decrease C. Stay the Same
2) If the temperature in the core of a star decrease what will happen next? http://aspire.cosmic-ray.org/labs/star_life/starlife_main.html

A. Gas pressure will decrease
B. gas pressure will increase
C. Density will Decrease
3) If gas pressure in the star in decreased then gravity will now be stronger than gas pressure. This
Stage 3
Stage 4
Stage 5 results in an unstable star. What should happen next?
A. The core will start to contract
B. The core will explode
4) The core has contracted. That means density has increased, and the atoms are closer together. If the atoms are closer together then their atomic collisions should:
A. Stay the same B. Decrease C. Increase
5. The atomic collisions have increased indicating that the temperature has
A. Increased B. decreased C. Stayed the same
6. If the temperature increases to a critical temperature for fusion, then the star will
A. Explode B. reach Equilibrium C. Collapse
Stars: The Beginning of The End
Helium Burning Interactive Lab
Stage 1 pressure
˄ gravity
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Stage 2 pressure
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˅ gravity
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Temperature
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Temperature
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˅ pressure
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˅ pressure
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___ gravity
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˅ gravity
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˅ gravity
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Temperature
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Temperature
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Temperature
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˅
What is a Red Giant?
˅ ˅
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Stars: The End Of A Star
What do low medium and massive stars become? Explain each.
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The end: Carbon Burning Interactive Lab
Stage 1 pressure temperature Gravity
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Stage 2
Stage 3 pressure
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˅ temperature
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Gravity
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Gravity
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Stage 4 pressure
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˅ pressure
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˅ temperature Gravity
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˅ http://aspire.cosmic-ray.org/labs/star_life/starlife_main.html

Stage 5 pressure
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˅ temperature Gravity
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What stage would you be in if you were a star?
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Super Giants a.Betelgeuse
Temperature ______________________
Brightness _______________________ b. alpha cantauri B
Temperature ______________________
Brightness ________________________ c. Our Sun
Temperature ______________________
Brightness ________________________
Main Sequence d. vega
Temperature _____________________
Brightness ________________________ http://aspire.cosmic-ray.org/labs/star_life/starlife_main.html

White Dwarfs e. Sirius B
Temperature _____________________________________
Brightness _______________________________________ http://aspire.cosmic-ray.org/Labs/StarLife/starlife_equilibrium.html
http://aspire.cosmic-ray.org/labs/star_life/starlife_main.html