NASA: National Aeronautics and Space Administration

  1. Question

    If the moon were smaller than it is, would total eclipses of the sun be impossible?

    Since the Moon just barely covers the Sun in a total solar eclipse (and sometimes, depending on its orbit, can't quite make it, producing an annular eclipse), there could be no total eclipses if the Moon were smaller, or farther away, or if the Sun were larger, or closer to us. You can find eclipses discussed in any introductory college text on astronomy as well as on many webpages.

    David Morrison
    NAI Senior Scientist

    July 31, 2003

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