Autumnal Equinox 9-22-08

Tomorrow is not only the beginning of cardboard boat building, it is also the beginning of autumn (all facts here are for the northern hemisphere, north of the tropics).

On the autumnal equinox, the sun crosses the celestial equator. During the summer, the sun had been rising north of east and setting north of west. After the equinox, the sun will begin to rise south of east and set south of west, further and further south until the winter solstice.

We think of autumn as the time of the waning sun, but actually the sun's rays have been getting "weaker," that is, less directly overhead, since the summer solstice.

Enjoy the season!