Why do partial eclipses of the moon occur more frequently then total solar eclipses?
The orbit of the moon around the Earth does not lie in exactly the same plane as the orbit of the Earth around the sun (the ecliptic). Accordingly, although the moon passes directly between the sun and the Earth very frequently, most of these times, it is not aligned perfectly with the sun. Because the moon has almost exactly the same apparent angular diameter as the sun, a nearly perfect alignment is required for a total eclipse. Fortunately, though, the moon’s orbit does lie pretty close to the ecliptic, so total solar eclipses still do occur fairly often.
