Aphelion: July 4th the earth is far from the sun and is said to be in Aphelion position. Aph means away and hellion means Sun. At this point the distance between the sun and the earth is 152 million km.
Perihelion: Jan 3rd the earth is nearest to the sun and is said to be in Perihelion position Peri means near, hellion means sun. At this point the distance between the sun and the earth is 147 million km.