What is the distance variation from perihelion to aphelion on earth?
The difference between the earth’s closest approach to its star and its furthest distance away from it depends on how “out of round” or how eccentric is the earth’s orbit around the Sun. Simplistically, this eccentricity varies periodically with a period of about 100 thousand years from 0.005 (almost perfectly circular) to about 0.058. The present eccentricity is 0.017 which yields a perihelion of about 91.405 million miles and an apelion of about 94.512 million miles. This varies from year to year.
