Celestia Forums

Here's my attempt at 3753 Cruithne and two other asteroids (2000 PH5 and 1998 UP1) that are co-orbital with Earth. I'm not sure how accurate an approximation the elliptical elements are--the 'horseshoe' motion still doesn't look quite right to me.

Here's some info on Cruithne:
http://www.astro.queensu.ca/~wiegert/3753/3753.html
Remember that the diagrams on the page are in a frame of reference that's fixed with respect to the Earth.

And here's the .ssc file:
http://www.shatters.net/celestia/files/atens.ssc

--Chris

chris wrote:Here's my attempt at 3753 Cruithne and two other asteroids (2000 PH5 and 1998 UP1) that are co-orbital with Earth. I'm not sure how accurate an approximation the elliptical elements are--the 'horseshoe' motion still doesn't look quite right to me.

Since these horseshoe orbits depend on the effect of Earth's gravity, I'd guess that a Keplerian ellipse would be particularly inaccurate for these asteroids-- you'd need a custom orbit to do well over long times.

I was playing around with the orbital specs for Cruithne and made an ssc file for it, then found this topic. ah well :)
Here's the info I used. Got it from http://cfa-www.harvard.edu/cfa/ps/NEO/TheNEOPage.html


"Cruithne" "Sol/Earth"
{
Mesh "asteroid.cms"
Texture "asteroid.jpg"
# Color copied from Eros
Color [ 0.52 0.47 0.42 ]
BlendTexture true
Radius 5

EllipticalOrbit
{
Period 365
SemiMajorAxis 149266010.157362
Eccentricity 0.51478431
Inclination 19.812285
AscendingNode 126.373212
ArgOfPericenter 43.640637
MeanAnomaly 40.048932
Epoch 2450500.5
}

Albedo 0.1
}


Don't know if that'll make it move more 'correctly' or not. I can't quite get my head around how it's supposed to be moving, even watching it in 3d