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Expert: Tom Whiting - 3/19/2008


Question
What is the circumference from pole to pole?

Answer
Polar diameter is 12,714 Km or very close to 7900 miles.
(12714 Km  x .6214 km/mile = 7900 miles).

Circumference = 2 Pi r but 2 radiuses equals one diameter, so new
equation is  C = Pi x D

Circumference = Pi D, which equals Pi, 3.1416... x 7900 miles
= 24,818.6 miles or you can safely round that off to 24,820 miles.

Or 39,942 Kilometers, if you want it in metric units.
Clear Skies,
Tom Whiting
Erie, PA
PS...for those physical constants of the Earth, see
http://en.wikipedia.org/wiki/Earth

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Tom Whiting

Expertise

I can answer most questions involving general science and engineering, except those involving electronics and computers.  My strong points are all the Earth Sciences, especially Meteorology and Astronomy, and any related subjects to Astronomy.  My weak point is Electronics Technology.   No astrology questions please, or questions about alleged UFO identifications.

Experience

My hobby has been Astronomy for over 50 years. I currently ownand use a 30 inch portable telescope.   I taught at the University Level for 13 years.  My personal interest in life, in general,  has always been science oriented.

Organizations
President - Erie County Mobile Observers Group for over 15 years.Member of allexperts.com astronomy catagory for over 8 years.

Publications
Astronomy Technology TodayErie Times Newspaper - I wrote the "Over Erie Skies" columnfor 11 years.

Education/Credentials
BS  Metallurgical Engineering Grove City College, PAMaster's Degree, Gannon University, Erie, PAAlso retired USAF pilot, 20 years.

Awards and Honors
I was the discoverer of the Mini-Coathanger Asterism up in Ursa Minor.  I earned 6 Air Medals with USAF and retired after 20 years of service with the rank of Major, with over 2100 hours flying time.I also earned the rank of Eagle Scout in 1956.

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