Unit 3 Flashcards
Where do sunspots occur
Where strong magnetic activity in the Sun’s outer layers cause relative cooling in small regions
Photosphere
Layer of the sun which emits the most visible light
Chromosphere
Outermost layer of the sun
Corona
Upper region of the chromosphere, where the solar atmosphere becomes much less dense
Granulation
Texturing in the surface on the sun
Convective Zone
A large area where cycles of material flow back and forth from the inner to the outer regions of the zone
Radiative Zone
Zone where energy travels outward. Material gets hotter between the boundary with the convective zone and the core
Nuclear fusion
Physical process which generates energy for the sun. Helps balance out the forces of gravity which would otherwise bring the outer layers crashing into the center
Proton-proton chain
Nuclear reaction series that powers the sun
Luminosity
Absolute power output at the source
Brightness
Apparent output as observed at a distance
Formula: Brightness = luminosity / 4 pi (distance)^2
Star temperature and absorption lines
The cooler a star gets ,the more atoms and molecules can hold on to electrons to create absorption lines
Distance in parsecs
1/parallax angle in arc seconds
High temperature stars are
Smaller and bluer
Lower temperature stars are
Bigger and redder
Increased luminosity doesn’t change the star’s color because
It doesn’t change the temperature, just the amount of light emitted
H-R Diagram
Hertzsprung-Russell Diagram, which shows the relationship between star luminosity and temperature
