Seasons occur because the Earth is tilted on her axis, not because of the distance from the sun. When the northern hemisphere is tilted away from the sun, it gets less sunlight, and the southern...
The earth is closest to the sun when it passes the point in its orbit called "perihelion". That time is always some time in the first couple of days in January. 2010 . . . January 3 2011 . . ....
The sun is approximately 1 AU (149,597,870.7 km. or 92,955,807.27 mi.) from the Earth. Compared to Mercury, the Earth isn't that close to the Sun, but compared to Jupiter or Saturn, it is pretty...