Aphelion is defined as the point in a planet's orbit that is

Aphelion is defined as the point in a planet's orbit that is

• A. Closest to the Sun
• B. Farthest from the Sun
• C. At the orbit's midpoint
• D. At the orbit's ascending node

Answer: (B)

In an elliptical orbit, the distance to the Sun changes as the planet travels. The farthest point from the Sun is aphelion, where the Sun’s gravitational pull is weaker and the planet moves slower in its path. The closest point is perihelion, where the planet speeds up as it moves nearer the Sun. The idea of an orbit’s midpoint isn’t a standard landmark for distance, and the ascending node marks where the orbit crosses the reference plane from south to north, not how far the planet is from the Sun. So the farthest point from the Sun is the correct understanding of aphelion.

In an elliptical orbit, the distance to the Sun changes as the planet travels. The farthest point from the Sun is aphelion, where the Sun’s gravitational pull is weaker and the planet moves slower in its path. The closest point is perihelion, where the planet speeds up as it moves nearer the Sun. The idea of an orbit’s midpoint isn’t a standard landmark for distance, and the ascending node marks where the orbit crosses the reference plane from south to north, not how far the planet is from the Sun. So the farthest point from the Sun is the correct understanding of aphelion.