Luminosity of the Sun

Luminosity means

luminosity = energy radiated per unit time

A convenient unit for measuring luminosity is watts (W). The luminosity of a 100 W lightbulb is (approximately) 100 W if you measure over all wavelengths. (Most of it is in the infrared; the part of the luminosity in visible wavelenghts is less.)

How can we measure the Sun's luminosity?

Davison E. Soper, Institute of Theoretical Science, University of Oregon, Eugene OR 97403 USA