Binary Stars Double StarsBinary Stars Earth Double Star
Binary Stars
Double Stars/Binary Stars Earth Double Star Binary Star
Visual Binary Stars Orbit of Star 1 Center of Mass Orbit of Star 2
Sirius A & B
Orbit of 12 Persei (Barlow, Scarfe, and Fekel
Visual Binaries o Stars must be either close to us or far from each other. m. Long orbital periods indicate they are far from each other. (years to decades) o About 10% of all stars are visual binaries o Possible planet detection
Spectroscopic Binaries Spectrum of Hydrogen in Lab Spectrum a Star…. . Day 1 Spectrum a Star…. . Day 2 Spectrum a Star…. . Day 3 Spectrum a Star…. . Day 4 What do these spectra tell us about the star?
Spectroscopic Binary Stars
Radial Velocity Curve HDE 226868
Spectroscopic Binaries o Orbital m Stars Periods are several days are close together inclined 90° to sky are discovered this way. o All of the extra-solar planets have been found in this way. o Orbits
Eclipsing Binary Stars
Roche Lobes
Classifications Detached 65 RT And Semi-detached 203 U Cep Over-Contact 12 XY Leo
Star Light Pro
Eclipsing Binaries o Chances of finding an eclipsing binary 90° to sky m Stars close together m Inclined o Same conditions as spectroscopic binary m Many are discovered in both ways o Eclipsing binaries also permit radius to be determined
Relative radius Eclipse begins separation = sum of radii Second contact separation = difference in radii Time difference between these events gives radii of stars
Mass-Luminosity Relationship
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