Asteroids

General physics and astronomy discussions not directly related to Celestia
Topic author
Jim L
Posts: 1
Joined: 05.10.2004
With us: 20 years 2 months

Asteroids

Post #1by Jim L » 05.10.2004, 21:11

I began creating an ssc for Aten asteroids. The code for the first two objects follows:

#
# Atens.ssc
#
# Data source http://cfa-www.harvard.edu/iau/lists/Atens.html
# Converted to Celestia format by Jim LaRoche, 05 Oct 2004,
# using Selden Ball's "How to transform orbital elements into Celestia's SSC format"
# http://www.lns.cornell.edu/~seb/celesti ... meris.html
#

# data source http://cfa-www.harvard.edu/iau/Ephemeri ... 4S56C.html
"2004 SC56" "Sol" #IAU's Prov. & Des.
{
Class "asteroid"
Texture "asteroid.jpg"
Mesh "asteroid.cms"
Radius 0.0325 #IAU H = 23 = 65 (useing 0.25 albedo) meters diameter /2 = 32.5m radius = .0325km
#Useing table "Conversion of Absolute Magnitude to Diameter" http://cfa-www.harvard.edu/iau/lists/Sizes.html

EllipticalOrbit
{
Epoch 2453200.5 #IAU's Epoch (Julian date)
MeanAnomaly 113.67710 #IAU's M (in degress,location in the orbit for the specified Epoch, angular distance from its perihelion)
ArgOfPericenter 322.32713 #IAU's Peri. (for J2000.0 in degress)
AscendingNode 202.56349 #IAU's Node (for J2000.0 in degress)
Inclination 4.64947 #IAU's Incl. (for J2000.0 in degress)
Eccentricity 0.4235061 #IAU's e (0.0-1.0, 0.0=circular, 1.0=eliptic)
SemiMajorAxis 0.7687391 #IAU's a (AU)
Period 0.67 #IAU's P (years)
}

Albedo 0.25 #proxy, actual value is unavailable/unknown; 0.5 for icy objects, most main-belt minor planet will have albedos in the range 0.05 to 0.25, from table "Conversion of Absolute Magnitude to Diameter" http://cfa-www.harvard.edu/iau/lists/Sizes.html
}

# data source http://cfa-www.harvard.edu/iau/Ephemeri ... 4S56B.html
"2004 SB56" "Sol" #IAU's Prov. & Des.
{
Class "asteroid"
Texture "asteroid.jpg"
Mesh "asteroid.cms"
Radius 0.180 #IAU H = 19.3 = 360 (useing 0.25 albedo) meters diameter /2 = 180m radius = .180km
#Useing table "Conversion of Absolute Magnitude to Diameter" http://cfa-www.harvard.edu/iau/lists/Sizes.html

EllipticalOrbit
{
Epoch 2453260.5 #IAU's Epoch (Julian date)
MeanAnomaly 178.31002 #IAU's M (in degress,location in the orbit for the specified Epoch, angular distance from its perihelion)
ArgOfPericenter 233.42900 #IAU's Peri. (for J2000.0 in degress)
AscendingNode 302.14512 #IAU's Node (for J2000.0 in degress)
Inclination 18.64561 #IAU's Incl. (for J2000.0 in degress)
Eccentricity 0.2371347 #IAU's e (0.0-1.0, 0.0=circular, 1.0=eliptic)
SemiMajorAxis 0.8661157 #IAU's a (AU)
Period 0.81 #IAU's P (years)
}

Albedo 0.25 #proxy, actual value is unavailable/unknown; 0.5 for icy objects, most main-belt minor planet will have albedos in the range 0.05 to 0.25, from table "Conversion of Absolute Magnitude to Diameter" http://cfa-www.harvard.edu/iau/lists/Sizes.html
}

Does any one see any errors (this is my first try at this)?

I have Celestia set for verbose and the temperatures shown for the objects are 261K and 256K.
Seems balmy!

Also, I noticed at IAU's site that they make their orbital element data availabe to import to several astronomy programs. Anything in the works between Celestia and IAU?

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