01:750:109 Chapter Notes - Chapter 8.2: Inverse-Square Law, Orbital Period, Binary Star
Document Summary
How much we know about stars other than our sun comes from measurements of 3 basic properties: Difference in brightness from the stars we see in the sky don"t tell us anything about how much light the stars are actually generating, because brightness also depends on distance. Ex: procyon and betelgeuse appear equally bright in our sky, but betelgeuse emits about. It has about the same brightness in our sky bc. Distinguishing between a star"s brightness in our sky and the actual amount of light it emits into space: Apparent brightness is the brightness of a star as it appears to our eyes. Luminosity is the total amount of power that a star emits into space (when we talk. Apparent brightness of a star (or any other light source) depends on both its luminosity and about how bright stars are in an absolute sense, regardless of their distance) distance. Apparent brightness obeys an inverse square law with distance.