aphelion

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The Word of the Day for July 1 is:

aphelion   \af-EEL-yun\   noun
      : the point in the path of a celestial body (as a planet) 
that is farthest from the sun 

Example sentence:
     If you live in the Northern Hemisphere, you might expect 
the earth to be closest to the sun in July, but in fact it is at 
aphelion then.

Did you know? 
     "Aphelion" and "perihelion" are troublesome terms. Which 
one means a planet is nearest the sun and which means it is 
farthest away? An etymology lesson may help you keep those words 
straight. Just remember that the "ap" of "aphelion" derives from 
a New Latin prefix that means "away from" (the mnemonic "'A' 
for 'away'" can help too); "peri-," on the other hand, 
means "near." And how are "aphelion" and "perihelion" related to 
the similar-looking astronomical pair, "apogee" and "perigee"? 
Etymology explains again. "Aphelion" and "perihelion" are based 
on the Greek word "helios," meaning "sun," while "apogee" 
and "perigee" are based on "gaia," meaning "earth." The first 
pair describes distance in relation to the sun, the second in 
relation to the earth.