Fusion
Stars along the main sequence are only fusing
____ --> ____ (elements).
H --> He
True or false: Absolute brightness depends on distance from the observer.
False - all absolute brightnesses are measured from 10 parsecs.
This is where most stars will spend most of their lives on the HR Diagram.
Main sequence
True or false: Parallax can be used to measure the distances to all stars we can see.
False
This is the ending stage of the most massive stars in existence.
Black holes
What is the relationship between the proton-proton chain and the CNO cycle?
Same net equation, and same net energy
This is the brightness as viewed from Earth.
Apparent Brightness/Magnitude
Which characteristic determines how a star will move on the HR Diagram?
Mass
Parsecs are used to measure (1) _______ and arcseconds are used to measure (2) ________.
distance...angles
This is also known as a "baby star."
Protostar
What is the heaviest element to fuse inside a star?
Iron
Absolute magnitude can also be called ___________. (one word)
Luminosity
Highest mass stars will spend their lifetime in this section of the HR diagram.
Top section (Giants and supergiants)
As parallax increases, distance _____________.
decreases
This event occurs right before the final stage of high mass stars.
Supernova
What reaction is taking place inside red giants?
____ --> ____
He --> C
Put the following stars in order from closest to farthest:
Cygni - orange
Procyon - blue, appears dimmer
Ross - red, appears brighter
Ross - Cygni - Procyon
Which two characteristics are plotted on an HR diagram?
Luminosity vs. surface temperature
1 arcsecond is 1/______th of a degree.
3600
List these star colors from coolest to hottest: red, blue, orange, white, yellow
Red, Orange, Yellow, White, Blue
What types of events are needed to form elements heavier than those fused inside stars?
Supernovae events
If two stars have the same apparent brightness, what can be assumed about their absolute brightnesses?
Nothing - you need to know their distances!
Write down the 7 stellar spectral classes in order from hottest to coolest.
O - B - A - F - G - K - M
What is the parallax of a star located 30 parsecs away?
D = 1/p --> 30 = 1/p --> p = 1/30 = 0.033 arcseconds
What is the relationship between mass and luminosity?
More massive = more luminous!