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Q & A: Dark sky and moonlight

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Most recent answer: 11/07/2010
Q:
why is sky dark at night? from where does the moon get light is moon light also a white light ?
- akatma (age 22)
INDIA
A:
Hello Akatma,

The night sky isn't quite all dark.  You can still light coming from stars as well as the moon.  The light of the moon is actually reflected light from the sun so it has a similar color as the sun but not quite because some wavelengths are reflected with different efficiencies than other. 

As you probably know our sun is really a star but as the earth is very near to it so the light from the sun completely dominates that of the distant stars.  Some stars have a more reddish color, some have a more bluish color.   This is due to the temperature of the star.  Very hot stars emit more blue light, cooler stars emit more red light.  This is a well known phenomenon and was figured out by the physicist Max Planck.  

LeeH

(published on 11/07/2010)

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