What is the perihelion and aphelion of earth? How are these distances calculated?

When Earth is closest to the Sun, it is called perihelion, and when it is farthest from the Sun, it is called aphelion.

The following formulas can be used to calculate these distances.

( 1 - e) = a Perihelion + ( 1 + e) = Aphelion

Whereas

E is the eccentricity of Earth's orbit around the Sun, which is roughly 0.017. a is the Semi-Major Axis of Earth's orbit around the Sun, also known as the Average distance between the Sun and the Earth, which is given by 149 million km.

Aphelion is equal to 1.496 ( 1 + 0.017) x 10^14 km.

Based on the elliptical shape of Earth's orbit around the Sun and the equations of planetary motion derived from Kepler's laws, the perihelion (the point in the orbit where Earth is closest to the Sun) and aphelion (the point in the orbit where Earth is farthest from the Sun) are calculated. The perihelion distance is approximately 147.1 million kilometers, while the aphelion distance is approximately 152.1 million kilometers.