A newly discovered planet orbits a distant star with the same mass as the Sun at an average distance of 128 million kilometers. Its orbital eccentricity is 0.5.
Find the planet’s ƒᴀʀтhest orbital distance from its star
2 Answers

(a+p)= 2 x average distance
a+p= 128 x 2
a+p= 256 million kilometers
ap= eccentricity x 2 x average distance
ap= .5 x 2 x 128
ap= 128 million kilometers
make it a 2 step equation:
128 + 2perihelion= 256
subtract 128 from both sides:
2perhelion= 128
divide each side by 2:
perihelion=64 million kilometers
aphelion= 256 – 64
aphelion= 192 million kilometers
check the answer by doing (ap) / (a+p) the answer should be .5
(19264) / (192+64)= .5
the answer is correct.

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