It is the most favourable time to consider why twilight lengths vary across latitudes with the swiftest transition being at the Equator as a location passes through the divisor and into the dark hemisphere of the Earth.

https://en.wikipedia.org/wiki/Deep_Space_Climate_Observatory#/media/File:EpicEarth-Globespin-tilt-23.4.gif

Apart from the Polar latitude where there is just a single sunrise and sunset each year arising from the planet's rotation as a function of its orbital motion, around the Equinox, the length of time the Sun remains in view is similar to the length of
time in spends out of sight across all latitudes.

As the planet turns once every 24 hours across all locations, the distance a location travels across the light hemisphere varies by latitude. This signifies the rotational velocity by latitude while keeping the physical consideration that all locations
complete a daily rotation at the same time.

Twilight lengths correspond to this rotational velocity as a location rotating at 1037.5 mph at the Equator experiences a rapid transition to darkness while a location closer to the Poles travelling at 600 mph will experience a longer transition to
darkness as it passes through the divisor at a lower speed.

The current belief is that twilight lengths vary because of some angle of solar descent is beneath contempt and more or less identify the dysfunction state of the relationship between solar system research and terrestrial sciences which rely on cause and
effect between dynamics and the Earth sciences.

https://en.wikipedia.org/wiki/Twilight

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