How much starlight reaches the surface of the Earth at night?

According to Allen's "Astrophysical Quantities" page 134, sky brightness is given in terms of the number of 10th magnitude stars per square degree in the visual band:

Air Glow at Zenith....................40
Zodiacal Light........................100
Faint Stars...........................320 on Milky Way
           ........................... 95 Off Milky Way
Diffuse Galactic Light................. 20
Total sky brightness at zenith........290
The Full Moon sky brightness is about 11,000 of the above units. For other units of light brightness, one 10th magnitude star per square degree equals 7.2 x 10^-11 stilb units. 1 stilb equals 1 lumen per square centimeter per steradian, and 1 candle power per square inch = 0.155 stilb units. Also a Foot-Lambert = 3.43 x 10^-4 stilb units.


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All answers are provided by Dr. Sten Odenwald (Raytheon STX) for the
NASA IMAGE/POETRY project.