User blog:Cerne/Polar flattening

Recently I attempted to determine how oblate my planet is (this is also called polar flattening, BTW), but before I continue I would like to point out that the formatting in my previous blog entries is not what it is supposed to be in a few areas. Something wierd happens to the formatting whenever I try to cut and paste text from somewhere else onto the blog entries. It happened in my first entry about Lagrange points - which I think was my third article but I am not sure - and I edited the entry once after I posted the entry but none of my other entries have been edited and I would like to keep it that way. That said, you will probably see more formatting errors in future blog posts.

Now on to the rest of the entry. Apparently Geoff's page is down. Which is unfortunate, but then I have been following that site a tad bit too much. I did manage to print out some of what was on it, including the equations I will be using in this entry. Basic equations are as follows:

ob = (re - rp) / re

obmax = (5*pi2*r3) / (G*M*T2)

obmin = obmax * 0.315

And the key:

re = Equatorial radius.

rp = Polar radius.

M = The planet's mass.

T = The length of a sidereal day in seconds.

G = The gravitational constant, 6.67*10^-11 or 0.000,000,006,67 (?).

pi = 3.14159 -> The number is much larger than this but it was understandably narrowed down quite a bit on Geoff's site.

My planet's statistics are as follows:

re = 4,100,000 meters. Cubed, it comes to 68,921e15.

rp = 3970850 meters.

M = 51,359,929e7 kilograms.

T = 68,928 seconds. Squared, it comes to 4,751,069,184.

And the rest of the equation:

pi2 = 9.8695877281

3,401,109,279,041,900,500,000 / 16,275,772,216,820,673.331,2

Here is what I ended up with:

ob = 0.0315

obmax = 208,967.613

obmin = 65,824.798

Somehow this still doesn't sound occurate to me but then I don't think I would really know. If anyone finds any mistakes with the equations, the approach I took or the results I got, please feel free to point them out. Any assistance with this matter would be appreciated as I appear to be inept. In the meantime, I am going to go forth with what I have right now.

Thanks for reading,

Cerne 15:12, September 22, 2010 (UTC)