Frequencies of solar and lunar eclipses
A solar eclipse, especially a total solar eclipse, can be seen from only a limited part of the earth, while the eclipsed moon can be seen at the time of the eclipse wherever the moon is above the horizon.
In most calendar years there are two lunar eclipses; in some years one or three or none at all occur.
Solar eclipses occur two to five times a year. Five is exceptional.
There were five solar eclipses in 1935 and will be again in 2206.
The average number of total solar eclipses in a century is 66 for the earth as a whole
Any point on the earth may, on the average, experience no more than one total solar eclipse in three to four centuries.
The situation is quite different for lunar eclipses.
An observer remaining in the same place can see 19 or 20 lunar eclipses in 18 years.
A total lunar eclipse can last as long as an hour and three-quarters, for a solar eclipse, the maximum duration of totality is only seven and a half minutes.
This difference results from the fact that the moon is much smaller in cross section than the extension of the earth’s shadow but can be only a little greater in apparent size than the Sun.
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