1) Go to Horizons and get the spice kernel
telnet ssd.jpl.nasa.gov:6775
type 2012 DA14, and say yes to do a name search. Once it finds it, type s to get an SPK kernel. Give the following answers:
SPK text transfer format [ YES, NO, ? ] : n
SPK object START [ t >= 1900-Jan-01, ? ] : 2013-Feb-01
SPK object STOP [ t <= 2101-Jan-01, ? ] : 2013-Mar-01
Binary SPK will be created, you will be asked to add more objects, say n.
Now you will get a download link, copy it to your browser and save it. It will be named something like wld17761.16.
2) Install Celestia
3) Create an extra for Celestia
Create a text file 2012_DA14.ssc in the extras folder and create a data folder within that folder. I needed to run a text editor as administrator to do this.
In the text file, paste the following text:
"2012 DA14" "Sol"
{
Class "asteroid"
Texture "asteroid.jpg"
Color [ 1.000 0.960 0.919 ]
BlendTexture true
Radius 0.025
SpiceOrbit
{
Kernel "2012_DA14.bsp"
Target "3599602"
Origin "SUN"
Beginning "2013 2 13"
Ending "2013 2 17"
BoundingRadius 1.5
Period 1.0
}
UniformRotation
{
Period 5.918
}
Albedo 0.048
}
4) Copy the spice kernel wld12345.16 to the extras/data folder and rename it 2012_DA14.bsp
5) Start up Celestia and look for 2012 DA14 in the solar system browser. It should be the last item under Sol. If it's not there, use ~ to bring up the debug screen and up and down to scroll it, and see if there are any errors for 2012 DA14.
Closest observed distance is just under 30000km. It travels from south to north past the night side of Earth.
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