Download Star Formation 1/18/2015

1/18/2015
Star Formation
Large Scale Star Formation
____________________(_____)
•Giant - millions of solar masses (M)
•Cool , around 10 K
•Molecules - H2, CO, CO2, CH, H2O, SiO, + many more
Size of cloud - large
Small compression area
Localized Star formation
Types of stars formed?
Sizes of stars formed?
____________- Few
____________- More
____________- Many, Many
OB Stars are the most influential
Characteristics?
_______!
Type of light?
_______
So?
_______ light ionizes Hydrogen
Produces large cloud of hot glowing gas - _____________
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OB Stars
H II Region
Orion
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Small Scale Star Formation
Less Mass - fewer stars formed
Harder to see - IR
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High Mass
Low Mass
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Main Sequence
Middle Age for stars
(and just about as exciting for them as for us)
What do MS stars do?
Why are more stars on the MS than anywhere else?
Are they happy?
What sort of retirement plan do they have?
What makes the Sun shine?
How does it produce energy?
The answer is.......
found in the ___________________________by Albert Einstein
E= _________
___________ - the fusing together of atoms to create energy
(Not fission the breaking apart of atoms)
More energy, less waste than fission
Why not do it on the Earth?
Requirements Densities around 100 gm/cc,
Temperature over 13 million K
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Step 1 - proton + proton  Deuterium, positron(e+), neutrino (n)
Positron
+
Two Protons
Deuterium
n
Neutrino
Step 2 - Deuterium + proton  He3, and energy
Proton
Helium 3
Deuterium
g
Gamma-ray
Step 3 - He3 + He3  He4+ 2 protons
Two Helium 3
Proton
Helium 4
Proton
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Proton - Proton Cycle - What goes in?
________________________________
What comes out?
________________________________
How much energy produced?
Gamma ray of 0.00000000004 Watts
That’s not much!
However, the Sun does this
100,000,000,000,000,000,000,000,000,000,000,000,000 times
every second!
End result  a lot of energy!
Energy is in the
Core
_____________ Zone
_______
How does it get
out?
With great
difficulty
_____________ Zone
________
____________
Zone
Photosphere
(surface)
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Main Sequence Trends
Uniform characteristics from top to bottom
At the top
_______ Mass
_______ Luminosity
_______ Temperature
_______ life
At the bottom
_______ Mass
_______ Luminosity
_______ Temperature
_______ life
MASS DETERMINES EVERYTHING!
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