Name: Eric
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A
Question:
Good day, I have often looked at the neither full nor new moon as dusk
approaches and the sky turns to a darker blue. Sometimes, I have noticed that the
dark part of the moon is darker than the sky itself - defining a circle of black
and white against the dark blue background. I have come across a phenomenon called
"earthshine" but that seems to be the process I describe in reverse: rather than
the dark portions appearing blacker than the sky, earthshine as I understand it
makes them appear lighter than the dark background. I must stress that this is
not the phenomenon I am talking about. My question is: how can the moon seem to
be darker than sky?
Replies:
Dear Eric,
The Moon is never darker "than the sky." Earth shine means light reflected from
the Earth lighting up the dark side of the Moon. If you look at this side with a
telescope you will see it glowing dimly. If you were on the Moon there, you would
see the Earth shining brightly.
NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.
