Monday, October 30, 2023

Partial Annular Solar Eclipse Oct 14 2023, Austin


Our area (Austin) was fortunate enough to behold a partial solar eclipse, clear skies and all. Texans in San Antonio, about 100 miles to the south, got a fabulous annular eclipse because of that area being in the zone of annularity.

My video combines two views of the same image frames used. One portion shows the sun aligned, and the other portion shows the sun drifting south a little as the mount was not perfectly polar aligned. I used tweaked versions (stationary sun, sun/moon movement) to build the side-by-side version.

The actual eclipse lasted over three hours. The resulting videos were each about 36 seconds. Over 900 frames made up each video segment. It was a learning process to prep and compile. Methodology for aligning the sun images using GIMP, my graphics editor, evolved over a few days. I used grids, circumscribed squares, circles, squares and circles, disk shapes.

I aligned using edges, then picking different edges as the moon advanced along its route.

Eclipse Resources

"What Is a Solar Eclipse?" and What Is an Annular Eclipse?" illustrate and simply explain solar and annular eclipses:

For an overview of the two main types of solar eclipses, Schreiner University's Eclipse Path site provides overall info about solar eclipse paths for October 14 2023 and April 8 2024. The NASA composite and Schreiner's video simulations for the two featured eclipses are view worthy. Nice to also see a short section about eclipse viewing safety.

"Types of Solar Eclipses" succinctly contrasts the three kinds of solar eclipses:

A total solar eclipse happens when the Moon passes between the Sun and Earth, completely blocking the face of the Sun. People located in the center of the Moon’s shadow ...

An annular solar eclipse happens when the Moon passes between the Sun and Earth, but when it is at or near its farthest point from Earth. Because the Moon is farther away from Earth, ...

A partial solar eclipse happens when the Moon passes between the Sun and Earth but the Sun, Moon, and Earth are not perfectly lined up. Only a part of the Sun will appear to be covered, giving it a crescent shape.

Reaching Back to the August 21 2017 Solar Eclipse

"Eclipse Map — August 21, 2017 Total Solar Eclipse" shows the path of totality as far away from our area, thus, why our eclipse image showed a crescent-moonish sun.