Axis coordinates in DSC are Ecliptic ?

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Cham M
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Axis coordinates in DSC are Ecliptic ?

Post #1by Cham » 15.08.2008, 15:58

I was banging my head all the day with the orientation of some DSC model (using the Axis [ ] and Angles commands), believing it was all Equatorial coordinates, until I noticed that it's actually Ecliptic !? Can someone confirm this ?

Axis [...] are Ecliptic in the DSC declaration ? Is that right ??
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Re: Axis coordinates in DSC are Ecliptic ?

Post #2by selden » 15.08.2008, 16:06

Celestia's "universal" coordinate system, which is what is used for DSC orientations, is the same as Ecliptic J2000.
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Re: Axis coordinates in DSC are Ecliptic ?

Post #3by Cham » 15.08.2008, 16:13

Thanks Selden.

Then I know exactly what to do. I just need to convert some Ra ; Dec coordinates to the Ecliptic system (and watch out for some axis flippings...).

Geez, all that time lost ! :evil:
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Re: Axis coordinates in DSC are Ecliptic ?

Post #4by Cham » 15.08.2008, 16:19

Is there a simple conversion tool on the net, which takes Equatorial coordinates and gives the Ecliptic coordinates ?

I just don't want to use the trigonometric formulas defined there (too long to use, after all that time lost for nothing) :

http://en.wikipedia.org/wiki/Ecliptic_coordinates
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Re: Axis coordinates in DSC are Ecliptic ?

Post #5by t00fri » 15.08.2008, 16:39

Cham wrote:Is there a simple conversion tool on the net, which takes Equatorial coordinates and gives the Ecliptic coordinates ?

I just don't want to use the trigonometric formulas defined there (too long to use, after all that time lost for nothing) :

http://en.wikipedia.org/wiki/Ecliptic_coordinates

How about placing this NASA URL into your bookmarks once for all ? ;-)

http://heasarc.gsfc.nasa.gov/cgi-bin/To ... nvcoord.pl

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Re: Axis coordinates in DSC are Ecliptic ?

Post #6by Cham » 15.08.2008, 16:40

Okay, I've found this nice conversion web page :

http://nedwww.ipac.caltech.edu/forms/calculator.html

Very usefull ! :wink:
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Re: Axis coordinates in DSC are Ecliptic ?

Post #7by t00fri » 15.08.2008, 16:43

Cham wrote:Okay, I've found this nice conversion web page :

http://nedwww.ipac.caltech.edu/forms/calculator.html

Very usefull ! :wink:

Did you see my post above yours?? ;-)

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Re: Axis coordinates in DSC are Ecliptic ?

Post #8by Cham » 15.08.2008, 16:52

Nope. Cross posting.

Thanks for the link.
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