Sky Watch: Changing positions of the sun

Around this time of year, I've had just about enough of winter. Granted, where I live in the desert of Southern California, it never become brutally cold, nor does snow ever fall, but still, enough is enough. So when I realize that spring is about to spring, well, so do I!Spring officially arrives this year to the Earth's Northern Hemisphere -- and autumn to the Southern Hemisphere -- at 1:14 a.m. on Tuesday, March 20. Astronomers know this exact moment as the "equinox."

For those at the onset of spring, this is the vernal equinox; for those entering the autumn season, it's the autumnal equinox. It marks when the sun crosses the celestial equator on its way north in the sky. Now days and nights are of nearly equal length ("equinox": "equal nights").

And as long as we don't concern ourselves with the fine details of our Earth's movement, that is a fairly true statement., it's necessary only to have a fixed observing location and to note the sun's setting or rising position from week to week.

To watch it, find a location where the sun sets behind distant landmarks, such as trees, houses or mountain peaks. Each day this week or next, return to that same spot late in the afternoon, and sketch the sunset position relative to those landmarks.

Be careful not to look directly at the sun itself, or you may suffer irreversible eye damage. You'll need only a few days to notice the northerly drift of the sunset point along the horizon and the increasing length of daylight, which lead to more pleasant temperatures on our part of planet Earth.