How much power on the Earth do we receive from the star Sirius?

The luminosity of Sirius is about 3.66 times the Suns or 1.4 x 10^27 watts. It is located 8.6 light years away or 7.96 x 10^16 meters. This means the power delivered to a square meter of the Earth by Sirius is: 


                27
        1.4 x 10     watts
      ---------------------
                         16  2         2
      4 x pi x (7.96 x 10   )    meters
or 1.7 x 10^-8 Watts/meter^2. By comparison, the Sun produces 1,369 Watts/meter^2.
Copyright 1997 Dr. Sten Odenwald
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