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A
The point in a planet's orbit at which it is farthest from the Sun — the opposite of perihelion, the point of closest approach.
— Astronomy reference
B
From the Greek apo (away from) and helios (sun) — literally the point away from the sun.
— Greek etymology
C
Earth reaches aphelion in early July each year, meaning the Northern Hemisphere's summer occurs when Earth is actually slightly farther from the Sun — demonstrating that seasons are caused by axial tilt, not distance.
— Orbital mechanics
D
At aphelion, Earth travels at its slowest orbital speed — Kepler's second law explains that planets sweep equal areas in equal times, moving slower when farther from the Sun.
— Kepler's laws
E
The difference between Earth's aphelion and perihelion distances is approximately 5 million kilometres — a variation of just over three percent of the mean orbital radius.
— NASA orbital data