What accounts for the variation in the Sun's apparent speed along the ecliptic throughout the year?

Answer

Earth’s actual orbit is an ellipse, causing its orbital speed to vary.

Earth’s orbit is elliptical; when Earth moves faster near perihelion (January), the Sun appears to advance more quickly along the ecliptic, and when Earth moves slower near aphelion (July), the apparent progress slows down.

What accounts for the variation in the Sun's apparent speed along the ecliptic throughout the year?

#Videos

The Ecliptic: Crash Course Kids #37.2 - YouTube

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