Magnitude, Brightness, Luminosity
This page covers the following topics:
The Hipparcos Scale catalogues stars in terms of their brightness. They are assigned a magnitude based on how bright they appear.
There are two factors that can effect the apparent brightness of a star: the distance it is from the earth and the amount of power it is emitting as visible wavelengths.
Absolute magnitude is how bright a star would appear if it was placed a distance of 10 parsecs from Earth.
If we measure the intensity, or brightness, of a star reaching Earth and we have a known value for luminosity, we can calculate how far away the star is by comparing it to a star with the same known luminosity.
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