Using Spice-data / How can i do that in an easy way?

General discussion about Celestia that doesn't fit into other forums.
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selden
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Post #21by selden » 05.06.2007, 14:19

Blueriver,

Here is the SSC catalog that I'm using:

Code: Select all

"Spice_SSB" "Sol"
{
   Color [ 1 1 0 ]
   Radius 100000

   OrbitFrame { EclipticJ2000 { Center "Sol"}}
   FixedPosition [ 0 0 0]
   BodyFrame {  BodyFixed { Center "Sol"}}
   FixedRotation {}

    Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "0"
                Origin "10"

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Mars_bary" "Sol/Spice_SSB"
{
   Color [1 1 0]
   Radius 100
   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB"}}

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"

     
      SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "4"
                Origin "0"
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}

# remove the # in the next line to make Celestia's Mars invisible
#Modify "Mars" "Sol" { Class "invisible" }

"Spice_Mars" "Sol/Spice_SSB/Spice_Mars_bary"
{
   Color [1 1 0]
   Radius 3396
   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Mars_bary"}}

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "499"
                Origin "4"
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_MRO" "Sol/Spice_SSB/Spice_Mars_bary"
{

        Class "spacecraft"

   Color [1 0 1]
   Radius 100

 #  Mesh "mro.cmod"
 #  Radius 0.011

   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Mars_bary"}}
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "-74"
                Origin "4"
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


and here's a Cel:// URL to take you to the viewpoint of the picture above:

Spice_MRO
Selden

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Blueriver
Posts: 17
Joined: 18.05.2007
With us: 17 years 6 months
Location: NorthGermany

Post #22by Blueriver » 05.06.2007, 14:30

Dear Selden,

i can tell a provisional result: The little mro-script with the four objects is working with 1.5.0pre1 and 1.5.0pre2 but not with 1.5.0pre3 .
I can not make it working on pre3 (german language) and I don`t know why it is so?€¦.i look to all settings but Celestia shows wrong spice-positions in (my) 1.5.0pre3.
I have made also minor changes to my other script (11 objects in the script: spice_Moon, spice_Venus, Venus_bary, spice_phobos, spice_deimos etc.) This script is also only working with pre1 and pre2:

Code: Select all

"Spice_SSB" "Sol"
{
   Color [ 1 1 1 ]
   Radius 100000

   OrbitFrame { EclipticJ2000 { Center "Sol"}}
   FixedPosition [ 0 0 0]
   BodyFrame {  BodyFixed { Center "Sol"}}
   FixedRotation {}

    Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "0"
                Origin "10" 

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Mars_bary" "Sol/Spice_SSB"
{
   Color [1 1 0]
   Radius 100
   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB"}}

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"

     
      SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "4"
                Origin "0" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Mars" "Sol/Spice_SSB/Spice_Mars_bary"
{
   Color [1 1 0]
   Radius 3396
   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Mars_bary"}}

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "499"
                Origin "4" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_MRO" "Sol/Spice_SSB/Spice_Mars_bary"
{
        Class "spacecraft"
   Mesh "mro.cmod"
      Color [1 1 1]
      Radius 0.50

   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Mars_bary"}}
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "-74"
                Origin "4"
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Phobos" "Sol/Spice_SSB/Spice_Mars_bary"
{
   Color [1 1 1]
   Radius 100
   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Mars_bary"}}
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"



   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "401"
                Origin "4" 

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"

      BoundingRadius 1e10
   }


}


"Spice_Deimos" "Sol/Spice_SSB/Spice_Mars_bary"
{
   Color [1 1 1]
   Radius 100
   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Saturn_bary"}}
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "402"
                Origin "4" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Earth_bary" "Sol/Spice_SSB"
{
   Color [1 1 1]
   Radius 100

   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB"}}
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "3"
                Origin "0" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Earth" "Sol/Spice_SSB/Spice_Earth_bary"
{
   Color [0 1 0]
   Radius 7000
   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Earth_bary"}}

   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"



   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "399"
                Origin "3" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Moon" "Sol/Spice_SSB/Spice_Earth_bary"
{
   Color [0 1 0]
   Radius 2000

   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Earth_bary"}}
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "301"
                Origin "3" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}



"Spice_Venus_bary" "Sol/Spice_SSB"
{
   Color [1 1 1]
   Radius 100
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"
   

   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB"}}

   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "2"
                Origin "0" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }


}


"Spice_Venus" "Sol/Spice_SSB/Spice_Venus_bary"
{
   Color [1 1 0]

   Radius 80000

   OrbitFrame { EclipticJ2000 { Center "Sol/Spice_SSB/Spice_Venus_bary"}}
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


   SpiceOrbit
   {
      Kernel "spk_psp_rec03736_03648_03736_r-v1.bsp"
               Target "299"
                Origin "2" 
   Beginning "2007 05 08 00:00:00"
      Ending    "2007 05 14 00:00:00"


      BoundingRadius 1e10
   }
}



Both scripts make use of the file: spk_psp_rec03736_03648_03736_r-v1.bsp

Btw. which program or part of the toolkit can show that a .bsp-file perhaps has gaps / is not usable with Celestia?

How can I make a U.S.english Version from my 1.5.0pre3?
I think the pre3 is Multilanguage depending on the pc-system.
I like to try out if the script is working with the 1.5.0pre3 English version.

When I now start my MRO.CEL script

Code: Select all

{
  renderflags {clear "orbits"}
  renderflags {set "planets"}
  labels {set "planets"}

  print  {text "Let's go first to Mars.."  row -3  column 1  duration 5}

  select {object "spice_mro"}
  follow {}
  goto   {time 5.0 distance 30}
  wait   {duration 5.0}



  print  {text "Now turn around our view and check Earth.."  row -3  column 1  duration 5}
  select {object "Earth"}
  center {time 3.0}
  wait   {duration 5.0}



  print  {text "Change now time and add light travel delay (hit '?' to display)."  row -3  column 1  duration 10}


}

goto spice_MRO correctly but the spice_Mars is obvious in some parts. So when I push the right mouse button there and turn a little bit around Mars is then visible as a planet again. I think I have to make little improvements that MRO.CEL and MRO.SSC can work together.
Do you have a suggestion what part of the .CEL has a mistake?

Thank you again for your help.
regards,
Blueriver

Topic author
Blueriver
Posts: 17
Joined: 18.05.2007
With us: 17 years 6 months
Location: NorthGermany

Post #23by Blueriver » 05.06.2007, 15:29

Dear Selden,
our postings today came accross...

I have to say a big thank you for your improved SSC catalog.

All is working fine but i have to use the 1.5.0pre2 for running the catalog correctly. No chance to run it with 1.5.0pre3(german language)

also the CEL:// URL (Spice_MRO) you gave is only working correctly with 1.5.0pre2

In my last posting i placed a little .CEL code. Could you please make a test with these .CEL-file on your system. When i get this running also with your catalog then i`m happy finally...

It should show me if the probe is in "line of sight to earth" or just behind mars (earth is not visible)

Thank you for all your help!
regards,
Blueriver

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selden
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Posts: 10192
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With us: 22 years 2 months
Location: NY, USA

Post #24by selden » 05.06.2007, 17:00

Blueriver wrote:Dear Selden,

i can tell a provisional result: The little mro-script with the four objects is working with 1.5.0pre1 and 1.5.0pre2 but not with 1.5.0pre3 .
I can not make it working on pre3 (german language) and I don`t know why it is so?€¦.i look to all settings but Celestia shows wrong spice-positions in (my) 1.5.0pre3.

Your SSC catalog and CEL script both work fine for me.
This suggests to me that perhaps your Spice catalog might not be using the same location for Sol that the rest of Celestia is using. Please make sure that there are no other Addons in the pre3 directory tree: just Celestia and the MRO Addon.

I have made also minor changes to my other script (11 objects in the script: spice_Moon, spice_Venus, Venus_bary, spice_phobos, spice_deimos etc.) This script is also only working with pre1 and pre2:

Code: Select all

"Spice_SSB" "Sol"
[ ... omitted ... ]


Both scripts make use of the file: spk_psp_rec03736_03648_03736_r-v1.bsp
Your long MRO .SSC catalog works fine for me with this BSP and Celestia v1.5.0 pre3.

Btw. which program or part of the toolkit can show that a .bsp-file perhaps has gaps / is not usable with Celestia?
SPACIT.EXE

How can I make a U.S.english Version from my 1.5.0pre3?
I think the pre3 is Multilanguage depending on the pc-system.
Yes.

I like to try out if the script is working with the 1.5.0pre3 English version.
I don't know how to force Celestia to use the English language interface. I think you can either set your system's Locale to be US English or you can disable Celestia's locale support. Maybe someone else can tell us how to do this.

When I now start my MRO.CEL script

Code: Select all

{
[... omitted ... ]
}

goto spice_MRO correctly but the spice_Mars is obvious in some parts. So when I push the right mouse button there and turn a little bit around Mars is then visible as a planet again. I think I have to make little improvements that MRO.CEL and MRO.SSC can work together.
Do you have a suggestion what part of the .CEL has a mistake?

There is nothing really wrong with your .CEL script although I would add steps in the middle to goto Mars
and to wait a little while after it gets there so you can watch the viewpoint moving.

You can see part of Celestia's Mars and part of Spice_Mars because they are at slightly different locations. Your SSC catalog adds Spice_Mars to Celestia but does not remove the original Mars, so Celestia draws them both.

If you do not want Celestia to draw its version of Mars, then you must make it invisible. Add this line to your SSC catalog:

Code: Select all

Modify "Mars" "Sol" { Class "invisible" }


I hope this helps.
Selden

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selden
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Posts: 10192
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With us: 22 years 2 months
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Post #25by selden » 05.06.2007, 17:20

Blueriver wrote:Dear Selden,
our postings today came accross...

I have to say a big thank you for your improved SSC catalog.

All is working fine but i have to use the 1.5.0pre2 for running the catalog correctly. No chance to run it with 1.5.0pre3(german language)

also the CEL:// URL (Spice_MRO) you gave is only working correctly with 1.5.0pre2

The URL can only work if the Spice SSC objects are defined correctly. If your MRO catalog isn't working, then the URL can't work, either.

This also suggests to me that you might be having problems because your copy of pre3 is damaged. Please delete pre3, download a fresh copy and install it.

In my last posting i placed a little .CEL code. Could you please make a test with these .CEL-file on your system. When i get this running also with your catalog then i`m happy finally...
As I said above, it works OK for me, although I would make some improvements with how it travels.

It should show me if the probe is in "line of sight to earth" or just behind mars (earth is not visible)
It does seem to do that on my system.

Thank you for all your help!
regards,
Blueriver

You're quite welcome.
Selden

Topic author
Blueriver
Posts: 17
Joined: 18.05.2007
With us: 17 years 6 months
Location: NorthGermany

Post #26by Blueriver » 05.06.2007, 20:14

Dear Selden,

thank you for your answers.
I have made now a complete uninstall of all (3) Cellestia versions i have had before on my pc system and i have made a new install of the 1.5.0pre3 only. ( it seems that it is tricky to have more than one version installed on the system)

Result: Wow, the script is running!

The only difference to the pre2 version is that i can`t see a spice_mro orbit as a red line around mars and that I have no shadow of the probe ?€¦.but that`s no problem.

When you have the time i would be happy if you could tell (show) me what improvements in detail belonging to the travel aspects of the .CEL-file you would add or change.

The next step for me in the next time is that i would like to build up another new spice_ script for other probes. I think it`s a very interesting aspect that Celestia can show these probe orbits?€¦ I`m only a hobby user without expert know how but together we can solve many things.

...perhaps there could be a spice-script area in the future at motherlode?

Thank you again for this learning unit how to handle Celestia with Spice-data.

PS: I will come with new questions in the next days, next week?€¦.

regards,
Blueriver

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selden
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Post #27by selden » 05.06.2007, 20:32

Blueriver,

I'm glad you got it to work.

I would add these steps to the .CEL script
1. set the date
2. go to Mars first -- travelling is half the fun!

e.g.

Code: Select all

time { utc "2007-5-9" }

select { object "Spice_Mars" }
  goto { time 1.0 distance 10}
  wait { duration 2}

 select {object "Spice_MRO"}
  center {}
  wait { duration 2 }

  follow {}
  goto   {time 1.0 distance 5 }


Have fun!
Selden

Topic author
Blueriver
Posts: 17
Joined: 18.05.2007
With us: 17 years 6 months
Location: NorthGermany

Post #28by Blueriver » 06.06.2007, 13:15

Dear Selden,
thank you again for posting the .CEL improvements.

Now the MRO.CEL looks like this

Code: Select all

{
  renderflags {set "planets"}
  labels {set "planets"}

  print  {text "Let's go first to Spice_Mars.."  row -3  column 1  duration 5}

  time { utc "2007-5-9" }

  select { object "Spice_Mars" }
  goto { time 1.0 distance 10}
  wait { duration 2}

  select {object "Spice_MRO"}
  center {}
  wait { duration 2 }

  follow {}
  goto {time 1.0 distance 5 }


  print  {text "Now turn around our view and check Earth.."  row -3  column 1  duration 5}
  select {object "Earth"}
  center {time 3.0}
  wait   {duration 5.0}

 
  print  {text "Change now time and add light travel delay (hit '?' to display)."  row -3  column 1  duration 10}




I think the viewposition at the end of mro.cel running is not so good (try Shift+*).
It would be better when there is a view from just behind spice_mro
Image

straight line to earth that we sometimes can visible see how spice_mars is going between spice_mro< >earth. (earth is than not visible for spice_mro)

How can i do this with the .CEL?


Could i generate the normal mars texture also for spice_mars?

....how ?

Thank you for your support and help.
Regards,
Blueriver

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selden
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With us: 22 years 2 months
Location: NY, USA

Post #29by selden » 06.06.2007, 13:39

Blueriver wrote:Dear Selden,
thank you again for posting the .CEL improvements.

Now the MRO.CEL looks like this

Code: Select all

[...omitted...]



I think the viewposition at the end of mro.cel running is not so good (try Shift+*).
It would be better when there is a view from just behind spice_mro
[ ... omitted ... ]

straight line to earth that we sometimes can visible see how spice_mars is going between spice_mro< >earth. (earth is than not visible for spice_mro)

How can i do this with the .CEL?
As best i can tell there is no CEL command equivalent to Capital-C. There is a CELX command, but that's a different language.

Code: Select all

observer:centerorbit(target)


Could i generate the normal mars texture also for spice_mars?

....how ?
Use Texture, NormalMap and any other surface texture statements that you want to use, just as for any other SSC object. You should read the SSC documentation that's on the MotherLode at http://www.celestiamotherlode.net/documentation.html
Selden

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Adirondack M
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With us: 20 years 8 months

Post #30by Adirondack » 08.06.2007, 06:23

Blueriver, Selden,

what is that dot?
One of the new discovered black holes? :-)

The dot is visible right from the start (2007 05 08 23:58:55 UTC at HUD / 2007 05 08 00:00:00 TDB) until 2007 05 10 00:09:24 UTC.

Image

I used the texture and atmosphere code of Mars form solarssys and made Mars invisible to see Spice_Mars only.

ForceWare 93.71

Adirondack
We all live under the same sky, but we do not have the same horizon. (K. Adenauer)
The horizon of some people is a circle with the radius zero - and they call it their point of view. (A. Einstein)

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selden
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Post #31by selden » 08.06.2007, 09:13

That dot is the eclipse shadow of a body that's inside the planet. It isn't cast "correctly" but there shouldn't be an interior body, anyhow :)

You can eliminate it by changing how the Spice barycenter objects are defined. You can either make them Class "invisible" or, more appropriately, you can define them as the new object type ReferencePoint. See the definition of Pluto-Charon in solarsys.ssc for an example of the latter's use.
Selden

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Adirondack M
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Post #32by Adirondack » 08.06.2007, 09:42

Ah, an eclipse shadow of a body inside of Mars, that are interesting news. 8O
There should not be such a body definitely inside of a planet. :)
Thanks for clarifying this strange phenomenon (and how to prevent this).

Adirondack
We all live under the same sky, but we do not have the same horizon. (K. Adenauer)

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Adirondack M
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Post #33by Adirondack » 08.06.2007, 20:44

Same with 'spice_ssb', otherwise the sun gets a huge greenish pimple:

Image

Adirondack
We all live under the same sky, but we do not have the same horizon. (K. Adenauer)

The horizon of some people is a circle with the radius zero - and they call it their point of view. (A. Einstein)

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selden
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Post #34by selden » 08.06.2007, 21:23

I'm not quite sure what you're trying to say.

All barycenters should be specified as ReferencePoints if you don't want to see them..

The pimple is Spice_SSB (Solar System Barycenter), drawn as Celestia's default sphere. I specified spheres for all of the barycenters in the original SSC file because I wanted to see where the barycenters were being placed. This is an Addon intended to test Celestia's Spice routines, not one designed for the production display of orbits and bodies.

Spice_SSB should be black instead of white because you're looking at its shaded side: it's an opaque body illuminated by the Sun. Its bright side is the side that is facing toward the center of the Sun and is hidden from view inside the Sun. You can see the inner side if you turn on Wire-Frame display ( Ctrl-W ). The side you see should be completely black if you have Ambient Light turned off. If it looks green to you, then you probably need to calibrate your monitor.
Selden

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Adirondack M
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Post #35by Adirondack » 08.06.2007, 23:02

I just wanted to say that I have noticed the SSB as a pimple while using your ssc catalog that starts with

Code: Select all

"Spice_SSB" "Sol"
and I did wonder whether this was intended (now I know it was). I just thought to mention my "discovery" for the case that somebody else uses your example too and one would wonder why this pimple comes up.
Thanks for your explanatory answer.

Adirondack
We all live under the same sky, but we do not have the same horizon. (K. Adenauer)

The horizon of some people is a circle with the radius zero - and they call it their point of view. (A. Einstein)

revent
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Post #36by revent » 11.06.2007, 03:45

selden wrote:I believe you are correct that a BSP file containing the trajectory of only one object can't work with Celestia. It needs to contain a second trajectory that can be used as the "Origin".


Actually an orbit with only one trajectory works just fine, if the coordinate origin used in the kernel is the same as the one you define in your ssc file.

The pic I posted a while back of Sol's barycentric orbit was made with a .bsp with only Sol in it, for example.

In general, though, yes you do need more than one orbit in the kernel. Most of the NAIF kernels use barycentric coords, so you need an orbit for Sol in the kernel to make Celestia like them.


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