Musings on the vernal equinox and celestial navigation

The New York Times has an op ed piece on its Opinion page that ruminates about the vernal equinox. The writer, Verlyn Klinkenborg, is learning celestial navigation and looks at the equinox with new eyes as a result (diagram is by artist Tau ‘olunga). We navigator types know that the vernal and autumnal equinoxes are the two days of the year when the earth experiences equal day and night. Thus the name equinox – equi: equal and nox: night, equal day and night. The sun crosses the equator and its declination goes to zero. All good celestial navigation stuff that occasionally even makes it into the NY Times.