Ch. 17 Flashcards
Star Color / Temp
Blue = hotter
(+White, +Yellow, + Orange)
Red = colder
Brightness / Magnitude
Larger magnitude = lower brightness
Apparent Brightness
The amount of energy that happens to reach our eyes or a telescope on Earth
Luminosity
Total amount of energy at all wavelengths that it emits per second
William & Margaret Huggins
First to identify lines in the spectrum of a star other than the Sun using spectrogram
Spectral Class of Stars
(hottest) OBAFKGKM (coolest)
- 10 subcategories
Absorption Lines
O Stars: ionized helium
A Stars: hydrogen lines
F Stars: ionized metals
M Stars: titanium oxied
Spectral Class of Stars
(hottest) OBAFKGKM (coolest)
- 10 subcategories w/numbers 0-9
Annie Jump Cannon
Created classification of stellar spectra
Brown Dwarfs
Masses intermediate between stars and planets; difficult to observe because faint + cool // spectral classes L, T, and Y
Dwarf Stars
Differ from typical stars due to different fusion process
Spectral Lines
Useful for when stars have same temperature but different pressure (low - narrow, high - broad)
Doppler-Shifted Stars
Red: star moving away
Blue: moving toward us
Proper Motion
Transverse from doppler; moves across our line of sight
Barnard’s Star
fastest moving star
