Archive for March 23, 2023

Tracking The Suns Shadow For An Entire Year, Using Two Methods

March 23, 2023

Beginning in (2022) my oldest grandson, needed a project to show the movement of the sun over a period of time….if possible an entire year. However, despite living more than 200 plus miles apart, we both made similar “solar devices” to measure the suns shadow, beginning on the Vernal Equinox (March 20th 2022) and beyond.

The white tape was placed on the first day of summer (June 20th 2022) which shows the longest day of the year. Note: the sun is not directly overhead using this method, as the shadow indicates.

I thought of a variation that I might try someday:  Put a straight pole into the ground, facing due south, and at an angle of 54 degrees (for you it would be 55 degrees)

Roger Ivester

My latitude is 35º 15′

(90º – 35º) = 55º

Debbie using an angle finder to insure the proper angle is at 55º.

The angle is toward the South at 55º

Point the steel rod toward North, but again the angle is toward the South. So draw a line, with the post, going South to North.

Note the shadow. It will be increasing each day to get shorter, until on September 22nd, there will be no shadow, as the sun will be “pointing down” the rod.

At 1:00 PM EDT, today (September 22nd) a photo was made, and indeed showing no shadow, as the sun was shining directly down the steel rod.

The previous marks (blue and yellow) on the scale indicate the positions of the suns shadow on different days, since August 24th.

The black mark shows the shadow on the first day of winter. The yellow mark was made on the longest day of the year….or the first day of summer.