Calculating spherical surface area - how?

   I'm trying to determine the surface area of a hypothetical planetary body,
given the circumference of that body (assuming it is a pefect globe with no
blemishes or terrain). Does anyone know the formula for this? I'm working in
kilometers, and suck at math. Please reply directly. Thank you!


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   Gregg Giles       Internet: [email removed]        FidoNet: sysop>1:152/18
   Sensory Overload (503/484-1281 USR HST DS) Anime VR Techno Digital Highway

      "I program my home computer, lead myself into the future." -Kraftwerk
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