That question may be answered by considering lunar eclipses. First, note that the frequency of lunar eclipses is not the same as the frequency of solar eclipses. Although the Earth is bigger than the Moon, so that it casts a larger shadow, the Moon is a smaller target for that shadow to hit and so, overall, lunar eclipses are not so numerous. There are on average 238 solar eclipses per century, but only 154 lunar eclipses.
Despite their comparative infrequency, for an observer restricted to one position on the terrestrial surface (say, an ancient Babylonian astronomer), lunar eclipses are witnessed more often than solar. This is because the full moon may be seen from anywhere on the night side of the planet. That implies that half of humanity might see the Moon being eclipsed, but in addition such eclipses last several hours, and the globe spins to allow observers elsewhere a chance to note the eclipse, even if all the phenomena may not be seen from the extreme locations.
An example of a lunar eclipse, that of May 16, 2003, is shown in Figure 2-5. Throughout South and Central America, and the Atlantic, the entire eclipse may be witnessed. The start of the eclipse, and all of the total phase, can be seen throughout the contiguous United States and most of Canada. The same is true for Europe and Africa. In the western parts of North America the Moon will be in eclipse as it rises. Europe will miss the final stages of the eclipse because the Moon sets during the process.
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