Stellar brightness
Compare the apparent brightness of two objects using the astronomical magnitude scale.
Your experiment
How it works
The magnitude scale runs backward: smaller numbers mean brighter objects. It is logarithmic, so a difference of five magnitudes corresponds to a factor of one hundred in brightness.
Read the field note ↗About this model
Both magnitudes must refer to the same photometric band. This compares received flux, not intrinsic luminosity. Symbol sizes use a compressed scale.
Stellar brightness: common questions
Can a magnitude be negative?
Yes. Very bright objects have negative apparent magnitudes. Zero is a reference level, not a lower limit.
What is absolute magnitude?
It is the apparent magnitude an object would have at a distance of ten parsecs, with extinction accounted for.
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