"Brenda Ann" wrote in message
news
"HFguy" wrote in message
news:uv1hi.10571$9b5.1632@trndny05...
Earth is closer to the Sun in Winter and further away from the Sun
in Summer.
This is true only for the northern hemisphere and it's not what causes
the seasons.
The Earth reaches perihelion - the point in its orbit closest to the Sun -
in early January, only about two weeks after the December solstice. Thus
winter begins in the northern hemisphere at about the time that the Earth
is nearest the Sun. Is this important? Is there a reason why the times of
solstice and perihelion are so close? It turns out that the proximity of
the two dates is a coincidence of the particular century we live in. The
date of perihelion does not remain fixed, but, over very long periods of
time, slowly regresses (moves later) within the year. There is some
evidence that this long-term change in the date of perihelion influences
the Earth's climate.
My bad, forgot the link/cite:
http://aa.usno.navy.mil/faq/docs/seasons_orbit.html