Hello I have a question about calculations of orbits. Mostly my question is about Comet orbits and eccentricity and period. To help myself learn more about orbits I'm witting a simple calculator for myself so I can better grasp it. I'm getting the orbital elements from the MPC website ( I cant post the url as I need 15 posts )(adsbygoogle = window.adsbygoogle || []).push({});

for a elliptical orbit e > 0 and e < 1

While Periodic Comets e (eccentricity)

name eccentricity

17P 0.432668

26P 0.633008

180P 0.357635

P/2006 HR30 0.842973

I see alot of comets list that have a e > 0 and e < 1 and they are not listed as a periodic comet.

name eccentricity

C/2006 M4 0.999933

C/2007 E2 0.999235

C/2007 T5 0.913398

This is just a few, but shouldn't they be listed as a periodic comet also?

I understand to get the semi major axis a = q/(1 − e)

and then to get the period is [tex]T=\sqrt{a^3}[/tex]

Comet C/2007 B2 Skiff

e 0.995869

q 2.974897

I get

a =720.13967562334

T = 19325.249433634 years

Does the IAU have a limit on the period time that they count a comet as periodic? I could not find it on their website.

thank you

Tony

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Calculations of orbits

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

**Physics Forums | Science Articles, Homework Help, Discussion**