Calc your shadow on the Equinox

I think, if I stood at the tropic of cancer, (between Cuba and Key West) today at noon my shadow would be 6′ long. Right?

  1. I need to know the altitude of the Sun. and recall a bit of trig (I’m kidding, I never really understood trig – ever) or I can use the interwebs: http://aa.usno.navy.mil/data/docs/AltAz.php

Astronomical Applications Dept.
U.S. Naval Observatory
Washington, DC 20392-5420

CHITTENDEN, VERMONT W 72 57, N43 43
Altitude and Azimuth of the Sun
Mar 20, 2017
Altitude Azimuth
(E of N)
h m o o
06:00 -10.7 79.7
06:10 -8.9 81.4

  1. At 12:10 and 13:50 the sun is at 45 degrees. Oddly, it actually gets a little higher between those times (who knows why?).

So my shadow will be 6′ long.   Nice. Equilateral

What’s my shortest and longest?

on June 21st at 13:00 the sun is at 69.7 degrees.

use http://www.calculator.net/triangle-calculator.html?vc=&vx=6&vy=&va=90&vz=&vb=21.9&angleunits=d&x=43&y=13

triangleCalc

So, on the summer solstice my shadow, at 1:00PM, is 2′ – 2 1/2″ long.

On December 20th the highest the sun gets up in the sky is 21.9 degrees and my shadow, at noonish is 14′ – 11″.

Leave a Reply

Your email address will not be published. Required fields are marked *