Earth's orbit around our closest star is elliptical, not circular. There's a point each year when we are farthest and then closest to the sun. Perihelion is the point where a planet is closest to the sun in its orbit.
The word comes from Greek "Peri" meaning close/near and "Helios" meaning sun.
Earth reaches its annual perihelion around two weeks after the winter solstice. The official time of perihelion comes at 1:54 a.m. Tuesday, Jan. 4. We'll be about 91 million miles from the sun.
Earth's orbit varies due to gravitational pulls from other things in the solar system so the orbit isn't exactly the same each year and perihelion's date and time change each year, as well
Aphelion, the farthest point in orbit to the Sun, comes in early July.