asteroid 2002 NT7

[postdan]

How can we see this asteroid in Celestia? I guess it was not included. Will it be?

[Sum0]

Code shamlessly stolen from ba22a (thanks!)

Code: Select all

"2002 NT7" "Sol"
{
   Class "asteroid"
   Mesh "asteroid.cms"
   Texture "asteroid.jpg"
   Radius 2.030

   EllipticalOrbit
   {
   Period 2.294964383 # 837.662 days
   SemiMajorAxis     1.739075636
   Eccentricity      0.530324939
   Inclination       42.3763219
   AscendingNode   132.1763308
   ArgOfPericenter  300.5607952
      MeanAnomaly     185.4742935
   Epoch           2452200.5
   }
    RotationPeriod   30.0
    Albedo            0.1
}

You know the routine - save it as a .ssc file in your extras directory.
Doesn't get too close to Earth, but quite near...

[ba22a]

I posted the parameters here yesterday, see the thread about the 'asteroid colliding with earth'. For fun last night I messed with the parameters a bit and got it to within 3000km... but those arent physical so I won't post them (the current position of the asteroid according to these figures and the position of the fake were too different)

I also found a nice list of the oribital elements of 1,942 near-earth objects, including 2002 nt7, which I converted to .ssc format. No sizes so they're all 1km blobs, and not interesting on their own, but its a bit of a shocker watching earth drifting along nonchalantly then turning on the asteroid labels...

[Guest]

ba22a, Out of interest where is that list

[ba22a]

http://neo.jpl.nasa.gov/cgi-bin/neo_elem

See also:
http://cfa-www.harvard.edu/iau/mpc.html

for a MUCH bigger list (167,000 objects!), including asteroids. To do a decent job of converting these for celestia, you want sizes and albedos as well. This link:

http://www.bitnik.com/mp/archive/Formula.html

gives three values for spectral slope G and corresponding average albedos; you can interpolate these to estimate albedo from G, the page then has a formula for the diameter of the object in terms of the albedo and H. H and G are given in the tables above.

[Guest]

Thank you

[timmy]

the radius is 1000 meters, not 2.

and here is somw more accurate code:

Code: Select all

"2002 NT7" "Sol"
{
   Class "asteroid"
   Mesh "asteroid.cms"
   Texture "asteroid.jpg"
   Radius 1000

   EllipticalOrbit
   {
   Period            2.29006 # 837.006 days
   SemiMajorAxis     1.737371050648156
   Eccentricity      0.5298591345915969
   Inclination       42.35242940965551
   AscendingNode   132.1668482301468
   ArgOfPericenter  300.6108078384685
        MeanAnomaly     -57.32033640196821
   Epoch       2452473.5
   }

   RotationPeriod   18.0
   Albedo            0.1
}



[NecroBones]

Assuming this last bit of code is actually accurate, the best "near miss" I've found was January 30, 2035. It comes within 5 million km. That's reasonably distant, yet close enough to use 10x binoculars to see the earth from the asteroid, and possibly make out a continent or two.. I think. :)

-Bones.