Intro and a Question About Ellipticity


by arakish
Tags: ellipticity, oblateness
arakish
arakish is offline
#1
Apr22-11, 11:01 AM
P: 4
My first post here. And I am wondering why I never found this forum before now...

I am an amatuer astronomer and astrophysicist in the truest sense. I have been interested in astronomy and astrophysics since watching ST:TOS when it first aired back in the 60s. I have also been interested in geography and cartography for the same length of time.

Without writing a novella, I am going straight to my question.

I suffered a severe HDD crash at the end of February. Like a dumb retard, I never kept backups. Some time back, I had found a website that listed an equation that would calculate a planet's ellipticity if one knew the planet's density, volumetric mean radius, and rotational period. I even wrote a program that would calculate this along with the planet's surface gravity, ballistic escape velocity, total surface area, equatorial mean radius, polar mean radius, mass, volume, and other data.

I have been searching the web trying to find this website again for the last two months. However, I have not been able to find it again.

My question: Anyone know of this website (or similar) and can me direct there? Or does anyone here know the equation?

Thanks for any help and for your valuable time spent reading and/or replying.

rmfr
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Drakkith
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#2
Apr25-11, 08:05 PM
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Wish I could help you. Can you not find all of those equations somewhere else listed by themselves or something? I wouldn't expect it to be too difficult to find them again, even if you don't find that original website.
IsometricPion
IsometricPion is offline
#3
Apr26-11, 12:43 AM
P: 177
Quote Quote by arakish View Post
Some time back, I had found a website that listed an equation that would calculate a planet's ellipticity if one knew the planet's density, volumetric mean radius, and rotational period.
The wikipedia page on "Equatorial bulge" has an equation for the flattening of an object in terms of density and rotational period. Using this and the mean radius I expect it wouldn't be terribly hard to obtain the ellipse of rotation and many of the values you desire based on wikipedia pages such as those on Angular eccentricity and Spheroids.

arakish
arakish is offline
#4
Apr28-11, 01:03 PM
P: 4

Intro and a Question About Ellipticity


Quote Quote by IsometricPion View Post
The wikipedia page on "Equatorial bulge" has an equation for the flattening of an object in terms of density and rotational period. Using this and the mean radius I expect it wouldn't be terribly hard to obtain the ellipse of rotation and many of the values you desire based on wikipedia pages such as those on Angular eccentricity and Spheroids.
Thank you very much IsometricPion. I never thought of doing a search on "Equatorial Bulge."

I guess for being somewhat smart, I can be a dummy. Thanks again.

rmfr


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