Monday, June 13, 2022

Early Bird Gets The Worm

If you open your copy of the 2022 Farmer's Almanac to page 144 you will note that in the Northern Hemisphere the earliest sunrise for this year is tomorrow - June 14.

You're probably thinking:  Shouldn't this coincide with the summer solstice next week?  Nope, the dates for the earliest sunrise (June 14) and the latest sunset (June 27) do not coincide with the Solstice (June 21).     

The principle cause of this is the slightly elliptical orbit of the earth around the sun and the tilt of the earth's axis.  The earth moves a bit faster in its orbit during the month of January when we're closest to the sun.  In July we are further from the sun and moving a bit slower.  If you chart the path of the sun across the sky on a daily basis it will appear to travel in a figure-eight pattern that astronomers call an analemma.  This is the Word of the Day.

    

Because of this, the notion that when the sun is directly overhead at noon, thereby slitting the day into to precisely equal parts, is not true.

The midday sun comes later by the clock on the day of the solstice than it does a week earlier.  As a consequence of this the sunrise and sunset times differ on a clock.  It is the sun's looping path that explains this difference.

I'm sure by now your head hurts a bit by this explanation so don't sweat the details.  Take my word for it. 

When you get-up tomorrow morning grab a big cuppa joe and watch the early sunrise.  And be sure to hang your flag out too.  It's Flag Day.  


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