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Heading to work the morning before the equinox
Turning onto M72 east in Acme I was presented with the sun half risen on top of the hill. This was taken a minute or so later.
03/19/2012 – Ephemeris – The last day of winter
Ephemeris for Monday, March 19th. The sun will rise at 7:46. It’ll be up for 12 hours and 7 minutes, setting at 7:54. The moon, 3 days before new, will rise at 6:30 tomorrow morning.
This is the last full day of winter. And a strange winter it is, ending today with record high temperatures. Tomorrow at 1:14 a.m. spring will officially start. At that time the earth will move to a point in its orbit where the sun will appear to cross the equator in the sky, and will appear to pass directly overhead if you lived on the equator. The event of the crossing and the point on the celestial sphere that the sun crosses the equator is called the vernal equinox. It’s the Greenwich of the heavens. All measurements east and west in the sky are measured from this point. And its position in relation to the prime meridian on the earth at Greenwich, near London is the fundamental measure of the earth’s rotational position.
* Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The sun at the vernal equinox. Diagram by Wikipedia contributor Tauʻolunga GNU Free Document License
Click on image to enlarge.
Bob Moler's Ephemeris Blog 