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    Assuming that the sun lies at the principal focus of the solar system, and given that the semi-major axis and eccentricity of Mars is 1.5237 AU and 0.0934 respectively, calculate:

    The distance (in AU) when Mars is closest to the Sun (known as perihelion). The angle θ=0°
    r = a(1 - e^2) / (1 +e cos θ)



    The correct solution is 1.38 AU

    Though if I use the above eqn putting a=1.5237 and e=0.0934 I get an answer of 16.17.

    Thanks for any help!
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    (Original post by little pixie)
    Assuming that the sun lies at the principal focus of the solar system, and given that the semi-major axis and eccentricity of Mars is 1.5237 AU and 0.0934 respectively, calculate:

    The distance (in AU) when Mars is closest to the Sun (known as perihelion). The angle θ=0°
    r = a(1 - e^2) / (1 +e cos θ)



    The correct solution is 1.38 AU

    Though if I use the above eqn putting a=1.5237 and e=0.0934 I get an answer of 16.17.

    Thanks for any help!
    I don't know why, quick substitution and the answer is what I get. You must be entering it into your calculator wrong.
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    I got it that time! Don't know what I was doing wrong...!
 
 
 
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