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Question
We see only one side of the moon because?
Hello,
The Moon rotates on its axis once every 27.3 days - which is *exactly* the same time period to make one revolution around the Earth.
This equivalence of rotation and revolution rate causes it to keep one face toward the Earth, in what we call "synchronous rotation."
The matching rotation and revolution rates is caused by tidal forces between the Earth and the Moon.
Technically speaking, we can sometimes get a "peek" of the other side of the Moon because of a "wobble" we call nutation. It is estimated that because of the lunar nutation we can actually see up to 6% of the other side.
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Answers by Expert:
Philip Stahl
Expertise
I have forty years of experience in Astronomy, specifically solar and space physics. My specialties include the physics of solar flares, sunspots, including their effects on Earth and statistics as applied to astronomical investigations.
Experience
Astronomy: more than forty years experience starting with construction of my own simple telescopes. Worked at university observatory in college, doing astrographic measurements. M.Phil. degree in Physics/Solar Physics and more than ten years as researcher.
Organizations
American Astronomical Society (Solar Physics and Dynamical Astronomy divisions), American Mathematical Society, American Geophysical Union
Publications
Solar Physics (journal), The Journal of the Royal Astronomical Society of Canada, The Proceedings of the Meudon Solar Flare Workshop (1986), The Proceedings of the Caribbean Physics Conference (1985). Books: 'Selected Analyses in Solar Flare Plasma Dynamics', 'Physics Notes for Advanced Level'.
Education/Credentials
B.A. Astronomy, M. Phil. Physics
Awards and Honors
American Astronomical Society Studentship Award (1984), Barbados Government Award for Solar Research
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