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## Angle of view - how very interesting Enthusiast

I was looking at my camera manual and ran across this:

The angle of view through the viewfinder is approximately 23.2 degrees and it hit me, that's almost exactly the degree of difference between the two solstices and the equinoxes.

73.2 minus 26.2 = 47.

47/2 = 23.5.

"On the Summer Solstice, the maximum altitude of the Sun as seen from a north latitude of 40.3 is 73.2 degrees; on the Winter Solstice, it's 26.2 degrees. This is because the Sun travels along the ecliptic, which is inclined by 23.5 degrees from the celestial equator. On the day of the Summer Solstice, the Sun is at the point on the ecliptic which is furthest above the celestial equator (i.e. add 23.5 degrees to the equinox value). On the day of the Winter Solstice, it's at the point which is furthest below the celestial equator (i.e. subtract 23.5 degrees from the equinox value).

The 23.5 degrees should sound familiar, as it's the angle by which the earth's axis is inclined to its orbit. The celestial equator is an extension of the earth's equator onto the sky. The ecliptic is a projection of the earth's orbit onto the sky. The earth's orbit projected onto the sky is equivalent to the Sun's path across the sky through the course of the year. The maximum altitude of the Sun is just a matter of the geometry of these two orbits."

Resource Library | Encyclopedic Entry Equinox

https://www.nationalgeographic.org/encyclopedia/equinox/

"So, equinoxes are the only times of the year when the subsolar point is directly on the Equator. The subsolar point is an area where the sun's rays shine perpendicular to the Earth's surface—a right angle. Only during an equinox is the Earth's 23.5° axis not tilting toward or away from the sun: the perceived center of the Sun’s disk is in the same plane as the Equator.

Before and after the equinox, the subsolar point migrates north or south. After the March equinox, the subsolar point migrates north as the Northern Hemisphere tilts toward the sun. Around June 21, the subsolar point hits the Tropic of Cancer, (23.5°N). This is the June solstice, after which the subsolar point begins to migrate south. After the September equinox, the subsolar point continues to move south as the Southern Hemisphere tilts toward the sun. Around December 21, the subsolar point hits the Tropic of Capricorn (23.5°S). This is the December solstice."

Taking pictures makes me feel like I am connected to the earth or something.

How very interesting.

Steve Thomas

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