When the earth is at perihelion, it is having its closest encounter with this
[DOC] [TLE] Perihelion, Aphelion and the Solstices - Timeanddate.com [PAR] The Earth is closest to the Sun  at its Perihelion  about two weeks after the 
December Solstice and farthest from the Sun  at its Aphelion  about two weeks
... [DOC] [TLE] Perihelion and aphelion - Wikipedia [PAR] The perihelion is the point in the orbit of a planet, minor planet, or comet, where it 
is nearest to its orbital focus, generally a star.