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    Re: Lunars barometric pressure correction
    From: Bill B
    Date: 2005 Apr 22, 16:42 -0500

    > Bill  wrote:
    > "Big difference between the two formulas when the elevation
    > gets into  miles."
    Frank replied:
    > Yes, and given today's cheap computing, might as well use the exponential
    > formula. By the way, you can also use it to answer the question "where does
    > space begin?" Just set the equation for density of the air:
    > density = exp(-altitude/34,000feet)
    > equal to 0 and solve for the altitude. :-)
    Having little success with modifying the formula with my math skills.
    Trying to manipulate the exponent and or find the nth root of zero has me
    off in deep space.
    Did try the plug and chug method with the TI-30, and ran out of computing
    power approx. 1277 nm. Looks like with enough computing power it could go on
    like pi.  Interesting as I would have thought the value would have been in
    the 60-120 nm range.  It did lead me to check out the Federation
    Aeronautique Internationale's definitions for outer space, which are located
    Two values that interested me:
    Reentry from orbit begins at 122 km
    100 km - Aerodynamic surfaces no longer function
    As to the bigger question, "where does space begin?" (Or end?) After
    reviewing the works of philosophers, mathematicians, and physicists--and
    using two TI-30Xa calculators simultaneously-- I arrived at the value "42."
    Back to Schaum's Theory and Problems of Basic Mathematics,

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