In its orbit around the sun. Just as it is during all the other seasons.
Referring to the seasons in the northern Hemisphere . . .
-- The Earth is slightly closer to the sun in Winter, and slightly farther from the sun
in Summer. (Yes. That's worded correctly.)
-- In Summer, the Earth is on the side of the sun that faces the center of the galaxy.
In Winter, it's on the side of the sun that faces away from the center of the galaxy.