When is the Earth nearest the sun?
It’s nearest the sun every year when it’s winter in the northern hemisphere and summer in the southern hemisphere, as the orbit is slightly elliptical. “Like all planets in our solar system, Earth travels around the Sun in an elliptical orbit,” explains astronomy professor George Lebo, a Summer Faculty Fellow at the NASA Marshall Space Flight Center. “We make our closest approach to the Sun (147.5 million km) in January, that’s called perihelion, and we’re farthest from the Sun (152.6 million km) in July, that’s aphelion. This year, aphelion falls on Independence Day in the USA.” http://science.nasa.