CCD imaging and theoretical modeling of lunar eclipses was begun in
1992. Some of the early results were described in Sky & Telescope,
September 1993. The aim of modeling is to reproduce photometrically
correct CCD imagery as accurately as possible. The two main aspects of
the model are Sun-Earth-Moon geometry which determines the appearance of
the partial phases almost completely, and refraction of sunlight in the
Earth's atmosphere which accounts for the appearance of totality.
Some of the more important findings of this research are that
Fred Espenak's eclipse page.
- the Moon's brightness during partial eclipse can be accurately modeled,
- the brightness during totality is also predictable though the observed brightness is sometimes less than expected due to the blockage of reflected sunlight by atmospheric aerosols,
- the 2% enlargement of the Earth's umbra that is used in ephemerides of lunar eclipse beginning and ending times is explained by atmospheric refraction modeling,
- the odd shapes and shadings reported during the partial phases are illusory phenomena probably caused by the dark mare versus bright highlands on the Moon itself, and
- perhaps the most important finding of all is that the aerosol induced dimmings of the eclipsed Moon correlate with temporary episodes of global cooling. The last finding has implications for Global Change Science.
Link to my
Galilean satellite eclipse timing page .
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