<< Most important is the fact that both the sun and the moon take up exactly
the same angular size when seen from the earth: this is why eclipses of the
sun are possible! Without eclipses of both the sun and the moon, it would
not have been possible, Kepler points out, for the ancients or the moderns
to have calculated the distances to the sun and the moon, and thus the
astronomical unit (he was a Copernican). He relies here on the calculation
of Aristarchus, which called for observations including some taken from
solar and lunar eclipses. And this makes it possible for us to get the
dimensions of the cosmos generally, etc. >>
The fact that we have total eclipses, that is, that the sun and moon appear
to be the same size, is a transitory condition in terms of cosmic time. The
moon is receding from earth at 3.8 centimeters per year, according to R.
Monastersky (Science News, 150 (July 6, 1996), p. 4. Thus in the distant
future it will no longer completely cover the sun's disc in a solar eclipse,
and the sun will more than cover the moon in a lunar eclipse. In the distant
past the moon appeared to be larger than the sun, being closer to earth, and
the sun did not completely cover the moon in a lunar eclipse.
This strikes me as another minor but interesting indication of the fitness of
the solar system and earth for human life so cogently argued by Michael
Denton in his book, _Nature's Destiny_. How considerate of God to place
humans on earth during the window of cosmic time in which total solar and
lunar eclipses occur and thus enabling scientists to make astronomical
calculations that enhances our understanding of the universe.