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Couple of ?'s on space craft installation ?

Posted: 23.07.2007, 13:09
by NicRic
Hi my Fellow Celestians ,
First of all I wanted to thank those who wrote the application for this wonderful web site and the download for Celestia ,its really a wonderful piece of software .I wish I had more knowledge on how to work within applications to gain the full benifits of what this one has to offer .Sadly for some reason Iam very good at working with hardware in PC's ,installing graphics cards ,TV Tuners ,replacing hard drives etc. However when it comes to the software I seem to a problem even when following directions and getting it to the desired outcome .What I would ike to try next with Celestia is adding a space craft from your menu of differant ones available ? Iam curious are you able to manuver these once installed and send them to a certain place in the soalar system ,or are they mostly just a added feature to add to the graphics of the app ? Anyone who can provide me some brief instructions and answer a couple of my ?'s ,I would greatly appreciate your taking the time to do so !
Take Care to All
Nick

Posted: 23.07.2007, 13:57
by selden
Nick,

Many spacecraft Addons are available on http://www.celestiamotherlode.net/

A description of how most Addons are supposed to work is available at http://www.lepp.cornell.edu/~seb/celest ... intro.html

Celestia v1.4.1 and older versions do not allow the positions of objects to be changed while Celestia is running. They all follow predefined orbits. The position of the viewpoint can be changed while Celestia is running, however.

Celestia v1.5.0 (currently in beta test) allows the definition of ScriptedOrbits, which make it possible to change the positions of objects while Celestia is running. However, you would have to write ScriptedOrbit and ScriptedRotation functions in Lua for that to work.

A crude example was recently posted to the Forum at
http://www.celestiaproject.net/forum/viewtopic.php?t=11243

I hope this helps a little.

Posted: 24.07.2007, 05:55
by LordFerret
I'll also note for you that certain spacecraft are only visable during specific date ranges... something I wasn't initially aware of when first installing Celestia v1.4.1.

For example, the default spacecraft in v1.4.1 - Cassini's Huygens, and the Galileo and MIR...
Huygens (Cassini) [beginning 15 Oct 1997 09:27 UT - ending 25 Dec 2004 02:01 UT]
Huygens (free) [beginning 25 Dec 2004 02:01 UT - ending 14 Jan 2005 09:00 UT]
Galileo [beginning 19 Oct 1989 02:47 UT - ending 21 Sep 2003 10:44 UT]
MIR [beginning 20 Feb 1986 12:00 UT - ending 21 Mar 2001 06:29 UT]

Most of the addon spacecraft of the past have their visable dates documented. If you run across one which isn't, you can view the addon's SSC file and look for the "Beginning" and "Ending" declarations - they define the dates the craft is visable. However, sometimes these declarations are expressed as a Julian date (such as 2436235.6583 - example taken from the Explorer 1 addon, "Launched 10:48 EST 31 Jan 1958") and will require the use of a calendar conversion utility to make sense of. You'll find such utilities in Seldon's List of Resources, lots of great references there... like the calendar conversion calculators!

:D

Posted: 24.07.2007, 13:13
by NicRic
I want to thank everyone that replied to my ?'s , must say as a amitted software idiot ,Iam probably more connfused then ever ,and also on the dated time frame these spacecraft are in orbit make it obvious to me that perhaps I should try some other kind of addon B/4 moving into the spacecraft categorey ?
Thanks Again ,Nick

Posted: 26.07.2007, 04:53
by LordFerret
I think you should give it a try, it's not that hard. Take MIR for example... just set the date in Celestia to 20 Feb 1986, select MIR and go to it. :D