Re: If our orbit around sun was circular would we still have four seasons?

Charlie,

Good question. One thing to remember is that while the earth is
revolving around the sun (in it's orbit) it is also rotatong
(spinning... which gives us our days and nights). If the earth was
spinning with it's axis perfectly oriented at a right angle to it's
orbital axis (straight up, like a top) then yes, we would have basically
the same season year round. However, the earth is tilted a bit from
being perfectly straight. This tilt actually has a GREATER effect than
the distance from the sun does. Infact, during our winter (in the
Northern Hemisphere) we are actually CLOSER to the sun than we are in
summer! The difference is that we (in the northern hemisphere) are
pointed more towards the sun in summer, and away from the sun in winter!
This tilt is also why the seasons in the southern hemisphere (like
Austrailia) are opposite from ours!

On an unrelated note, I was delighted to get this e-mail, as I am
originally from Mississippi, and am working in Washington D.C. now! I
have been to Ocean Springs many time, especially to the all of the
Walter Anderson artifacts. I hope you are having a good summer!

Good Luck!

J. Scott Miller, Ph.D.