Merry Equinox

[plennis]

Merry Equinox to all residents of planet Earth. On this day, Earth’s tilted axis points neither towards nor away from the Sun.
Astronomically, that gives us Spring north of the equator, and Autumn south of it.
Also 12 hours of daylight and 12 hours of nighttime - worldwide.
But if you check the sunrise/sunset tables worldwide, you will notice slightly more than 12 hours of sunlight for today.  Mostly caused by the refraction of sunlight entering Earth’s atmosphere from space.  When you see the Sun rise, what you actually see is the location of the Sun’s refracted light, and not the location of the Sun itself.  The actual Sun does not rise for another several minutes. Refraction at sunset delays what you see by several minutes as well.
Also, the part of the Sun that peeks above the horizon at the moment of sunrise, is a different part of the Sun (sitting a whole diameter away) from what’s referenced for sunset.
Combined, these phenomena add multiple minutes of unearned daylight that wouldn't otherwise be there.

[ssarber]

And a happy Birthday to my mom also today!