Originally Posted by DaveC426913
Is this true?
(excerpted from an article about 2003 UB313)
"...Its very elongated orbit takes it up to 97 times farther from the Sun than is the Earth - almost twice as far as the most distant point of Pluto's orbit – so that it takes twice as long as Pluto to go around the Sun..."
Is there a direct correlation between orbital diameter and orbital period? .
|
Yes there is.....
but they've made very rough verbal approximations.
Actually to make orbital period determinations you must use the semi-major axis of the orbit.
In this case the semi- major axis of UB313 is 67.7 AU compared to Pluto's 39.5 AU. So it is really only 1.7 times as distant as Pluto.
The orbital period vs. orbital radius (s-m axis) scales as T^2/R^3, (Kepler's law).
So the period T = sq.rt.(1.7)^3 = 2.25, meaning its orbital period is 2.25 times that of Pluto.
Since Pluto's orbital period is 248 yrs, then the orbital period of UB313 is about 558 yrs. -- Approximately since all my figures are truncated.
Creator
