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spaceboy0
2008-Mar-31, 02:54 AM
What is the minimum and maximum number of Solar and Lunar eclipses possible in a year? Is it possible to have no eclipses in a year?

a1call
2008-Mar-31, 03:34 AM
The best answer seems to be:


Within a given year, a maximum of seven eclipses can occur, either four solar and three lunar or five solar and two lunar. Despite the fact that there are more solar than lunar eclipses each year, over time many more lunar eclipses are seen at any single location on earth than solar eclipses. This occurs because a lunar eclipse can be seen from the entire half of the earth facing the moon at that time, while a solar eclipse is visible only along a narrow path on the earth's surface.

Source (http://www.answers.com/topic/eclipse?cat=technology)

The minimum is two.

grant hutchison
2008-Mar-31, 08:10 AM
If seven eclipses are packed into the year, then at least some of the solar eclipses will be partial, because they must occur close to the start and end of the "eclipse seasons". You can get three eclipses into any given eclipse season (solar-lunar-solar), and there is room for two full eclipse seasons and a partial eclipse season in a calendar year, so a seventh eclipse can be squeezed in before the end of the year.
The year 1935 had the classic rhythm for a "five solar + two lunar" eclipse year. The first eclipse season started in early January, with a partial solar eclipse on 5 January, a total lunar eclipse a fortnight later on 19 January, and then the season finished with another partial solar eclipse on 3 February. The second eclipse season ran through the same sequence, with a partial solar on 30 June, a total lunar on 16 July and another partial solar on 30 July. Finally, the third, partial season squeezed in an annular solar eclipse on 25 December, but with no time for a lunar eclipse before the end of the year; after a fortnight, the subsequent lunar eclipse fell on 8 January 1936.
In 1982, we got the classic pattern for a "four solar + three lunar" year. The year started partway through an eclipse season, allowing a lunar and then a solar eclipse in January, a solar-lunar-solar sequence in mid-year, and a solar followed by a lunar in December; but there was no room at either the start or the end of the year to fit in another solar eclipse.

Grant Hutchison