(Submitted March 02, 1998)
Is there any night time on the Moon? Is the Moon's daylight the same as the
Earth's daylight or is it brighter?
The moon orbits the earth with a period of four weeks ( a
month) and during the orbit it always has the same side facing the earth.
So this means that on the moon there is day and night, but they are both
two weeks long instead of 24 hours.
The Moon's daylight is brighter and harsher than the Earth's. There
is no atmosphere to scatter the light, no clouds to shade it, and no
ozone layer to block the sunburning ultraviolet light.
The nights are also brighter, at least on the side of the Moon
near to us. The night is lit up by sunlight reflected from Earth, while
the night on Earth is lit up by sunlight reflected from the Moon. Earth
is much bigger than the Moon, and Earth is also more reflective (with its
clouds and oceans, it reflects more light than the dark Moon rocks).
Earthlight on the Moon is much brighter than Moonlight on the Earth.
Hope this helps,
Jeff Silvis and David Palmer
For Ask an Astrophysicist
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