perihelion

The point in a planet's orbit when it is closest to the sun. Earth reaches perihelion in early January — counterintuitively, the Northern Hemisphere's winter. The opposite is aphelion, the farthest point, in early July. The difference is small (about 3 million miles) and has little effect on seasons, which are driven by axial tilt, not orbital distance. But the words are beautiful — they name the geometry of our path around the star.