SPICE module

[jarmonik]

I want to add into module ability to compute approximate elliptical trajectories over the kernel interval.

I suppose this approximation belongs to the Orbiter. But I could be wrong about it.

But without EPHEM_PARENTBARY it's not possible

Why Not ???

Seems like Orbiter has all data to compute Pluto position (masses of all bodyes in *.cfg) - but Pluto appears at PLUTO BARYCENTER

I don't know how Orbiter handles the EPHEM_PARENTBARY flag. Would it be possible to compute the position of the pluto barycenter relative to the Sun not SSB. What about computing Charon/Nix/Hydra relative to Pluto not Pluto barycenter ?

I suppose Martin would know the answers.

 

[jarmonik]

These are the replies of current modules:

[COLOR=#808080](Tue Apr 22 22:55:30 2008 )[/COLOR] 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Requesting True Pos&Vel
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] -----------------------
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Sun: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Jupiter: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Saturn: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Neptune: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Uranus: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Earth: EPHEM_POLAR EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Venus: EPHEM_POLAR EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Mars: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Mercury: EPHEM_POLAR EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Ganymede: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Titan: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Callisto: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Io: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Moon: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Europa: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Triton: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Titania: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Oberon: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Rhea: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Iapetus: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Ariel: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Umbriel: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Dione: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Tethys: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Enceladus: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Miranda: EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Mimas: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Hyperion: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Phobos: EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Deimos: EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Requesting Bary Pos&Vel
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] -----------------------
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Sun: EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Jupiter: EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Saturn: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Neptune: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Uranus: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Earth: EPHEM_POLAR EPHEM_TRUEPOS EPHEM_TRUEVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Venus: EPHEM_POLAR EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Mars: EPHEM_POLAR EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Mercury: EPHEM_POLAR EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Ganymede: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Titan: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Callisto: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Io: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Moon: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Europa: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Triton: EPHEM_TRUEPOS 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Titania: EPHEM_TRUEPOS 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Oberon: EPHEM_TRUEPOS 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Rhea: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Iapetus: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Ariel: EPHEM_TRUEPOS 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Umbriel: EPHEM_TRUEPOS 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Dione: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Tethys: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Enceladus: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Miranda: EPHEM_TRUEPOS 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Mimas: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Hyperion: EPHEM_BARYISTRUE EPHEM_TRUEPOS EPHEM_TRUEVEL EPHEM_BARYPOS EPHEM_BARYVEL 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Phobos: EPHEM_TRUEPOS EPHEM_BARYPOS 
[COLOR=gray](Tue Apr 22 22:55:30 2008 )[/COLOR] Deimos: EPHEM_TRUEPOS EPHEM_BARYPOS

 

[Ajaja]

I suppose this approximation belongs to the Orbiter. But I could be wrong about it.

Every SPICE kernel has time restrictions. For example, for plu017.bsp it's 1990 JAN 01 - 2050 JAN 01. So, to avoid of disappearance Pluto/Charon/... before 1990 JAN 01 and after 2050 JAN 01 I'm trying to add this approximation in simplest way - using elliptical orbits.

But without EPHEM_PARENTBARY it's not possible

Why Not ???

Yes, it's possible, but needs a lot of computations. I don't want to overload module. The main goal - is SPICE support.

What about computing Charon/Nix/Hydra relative to Pluto not Pluto barycenter ?

Nix/Hydra rotates around barycenter, not Pluto. Pluto system barycenter is far away from Pluto's body center. So it's impossible to define orbit around Pluto using set of orbital elements (eccentricity,inclination,etc..), only around barycenter. And it's impossible to define simple elliptical orbit of Pluto around Sun - only orbit of Pluto barycenter around Solar System Barycenter. Otherwise - huge inaccuracy.

 

[jarmonik]

It seems that Charon is much more massive than I first thought and that makes Pluto Charon system somewhat unique. Nix and Hydra are greatly effected by both objects. I see.

 

[Chode]

Firstly, for planetary modules, true and barycentric positions are relative to the barycenter of the solar system, even though they don't report EPHEM_PARENTBARY. So you should be able to create a satisfactory elliptical orbit for the Pluto-Charon system barycenter relative to the SSB. I'm not sure if I am understanding the problem you are seeing, but it sounds like your spice module for Pluto is returning only the position of the Pluto-Charon barycenter, and that is causing Orbiter to place Pluto at that position rather than computing it's correct position based on the other moons. Is that a correct understanding?

For Charon, I assume you are returning EPHEM_PARENTBARY and also returning the true and barycentric positions. (EDIT: yes, you already said that, sorry) Does Orbiter place Charon in the correct position?

Regards

 

[jarmonik]

Firstly, for planetary modules, true and barycentric positions are relative to the barycenter of the solar system, even though they don't report EPHEM_PARENTBARY.

That was an important piece of information, Thanks Chode.

 

[Chode]

Oops, I got my data switched. The true and barycentric positions of the planets in Orbiter are relative to the position of the Sun, not the SSB, so the non-reporting of EPHEM_PARENTBARY would be correct. Sorry about the mix-up.

So, if your planet module reports EPHEM_PARENTBARY, the expected result would be for Orbiter to offset the position of the planet by the difference in position of the SSB relative to the Sun. It sounds like this may not be happening. This would not be a problem for the base Orbiter package, since no planets report EPHEM_PARENTBARY.

Another case would be if your planetary module gave only barycentric positions and velocities, then you would expect Orbiter to correctly compute the true position of the planet based on the positions of all of the other bodies in the system, and it sounds like this also may not be happening.

I plan on doing some further tests to try to better define what Orbiter is doing in these cases.

Regards

 

[Chode]

I've done some more testing and I can confirm that there is a problem with the way Orbiter behaves when you report EPHEM_PARENTBARY. Basically, it looks like it ignores it, and always computes positions relative to the parent true position, and not the parent barycenter. I've reported this behavior in the Bug Report forum.

It also appears that Orbiter fails to correct the true position based on the other bodies in the system, if the ephemeris gives only the barycenter position, but I have some more testing to do to verify that.

Regards

 

[toodoo213]

Did I installed everything correctly? because when i load a scenario this is what happens

**** Orbiter.log
Build Sep 29 2006 [v.060929]
Found 0 joystick(s)
Module AtlantisConfig.dll [API v.060425]
Module DGConfig.dll [API v.060425]
Module TrackIR.dll [API v.060425]
TrackIR module not found.
Module ScnEditor.dll [API v.060425]
Module Rcontrol.dll [API v.050206]
Module OrbiterSound.dll [API v.060425]
Module Meshdebug.dll [API v.060425]
Module Framerate.dll [API v.050206]
Module FlightData.dll [API v.050206]
Module ExtMFD.dll [API v.060425]
Module CustomMFD.dll [API v.060425]
Module Orulex-core.dll [API v.060425]
Module MapMFD.dll [API v.050206]
Module OrbConnect.dll [API v.060425]
**** Creating simulation session
DirectDraw interface OK
Direct3D interface OK
Zbuffer: 32 bit
Render device: Window 894 x 649
Device has hardware T&L capability
Module spice.dll [API v.060425]
spice.dll: Kernel Kernels\de421.bsp was loaded successful.
spice.dll: Object SUN was loaded successful. Valid time interval: 14864.000000 MJD to 71184.000000 MJD
spice.dll: Object MERCURY was loaded successful. Valid time interval: 14864.000000 MJD to 71184.000000 MJD
spice.dll: Object VENUS was loaded successful. Valid time interval: 14864.000000 MJD to 71184.000000 MJD
spice.dll: Couldn't load kernel: Kernels\jup230.bsp
spice.dll: Couldn't find object IO in SPICE kernel pool!
spice.dll: Couldn't find object EUROPA in SPICE kernel pool!
spice.dll: Couldn't find object GANYMEDE in SPICE kernel pool!
spice.dll: Couldn't find object CALLISTO in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernels\sat252s.bsp
spice.dll: Couldn't find object MIMAS in SPICE kernel pool!
spice.dll: Couldn't find object ENCELADUS in SPICE kernel pool!
spice.dll: Couldn't find object TETHYS in SPICE kernel pool!
spice.dll: Couldn't find object DIONE in SPICE kernel pool!
spice.dll: Couldn't find object RHEA in SPICE kernel pool!
spice.dll: Couldn't find object TITAN in SPICE kernel pool!
spice.dll: Couldn't find object HYPERION in SPICE kernel pool!
spice.dll: Couldn't find object IAPETUS in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernels\ura083.bsp
spice.dll: Couldn't find object MIRANDA in SPICE kernel pool!
spice.dll: Couldn't find object ARIEL in SPICE kernel pool!
spice.dll: Couldn't find object UMBRIEL in SPICE kernel pool!
spice.dll: Couldn't find object TITANIA in SPICE kernel pool!
spice.dll: Couldn't find object OBERON in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernels\nep076.bsp
spice.dll: Couldn't find object TRITON in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernels\nep077.bsp
spice.dll: Couldn't find object NEREID in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernels\plu017.bsp
spice.dll: Couldn't find object CHARON in SPICE kernel pool!
spice.dll: Couldn't find object NIX in SPICE kernel pool!
spice.dll: Couldn't find object HYDRA in SPICE kernel pool!
Finished initialising world
Module MG_Atlantis.dll [API v.060425]

This is what happens

all the planets are one!

 

[Ajaja]

spice.dll: Couldn't load kernel: Kernelsjup230.bsp
spice.dll: Couldn't find object IO in SPICE kernel pool!
spice.dll: Couldn't find object EUROPA in SPICE kernel pool!
spice.dll: Couldn't find object GANYMEDE in SPICE kernel pool!
spice.dll: Couldn't find object CALLISTO in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernelssat252s.bsp
spice.dll: Couldn't find object MIMAS in SPICE kernel pool!
spice.dll: Couldn't find object ENCELADUS in SPICE kernel pool!
spice.dll: Couldn't find object TETHYS in SPICE kernel pool!
spice.dll: Couldn't find object DIONE in SPICE kernel pool!
spice.dll: Couldn't find object RHEA in SPICE kernel pool!
spice.dll: Couldn't find object TITAN in SPICE kernel pool!
spice.dll: Couldn't find object HYPERION in SPICE kernel pool!
spice.dll: Couldn't find object IAPETUS in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernelsura083.bsp
spice.dll: Couldn't find object MIRANDA in SPICE kernel pool!
spice.dll: Couldn't find object ARIEL in SPICE kernel pool!
spice.dll: Couldn't find object UMBRIEL in SPICE kernel pool!
spice.dll: Couldn't find object TITANIA in SPICE kernel pool!
spice.dll: Couldn't find object OBERON in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernelsnep076.bsp
spice.dll: Couldn't find object TRITON in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernelsnep077.bsp
spice.dll: Couldn't find object NEREID in SPICE kernel pool!
spice.dll: Couldn't load kernel: Kernelsplu017.bsp
spice.dll: Couldn't find object CHARON in SPICE kernel pool!
spice.dll: Couldn't find object NIX in SPICE kernel pool!
spice.dll: Couldn't find object HYDRA in SPICE kernel pool!

Look into Config\*.cfg - module tries to load corresponding bodies from jup230.bsp, sat252s.bsp,... but cann't find theirs.

 

[toodoo213]

Look into Config*.cfg - module tries to load corresponding bodies from jup230.bsp, sat252s.bsp,... but cann't find theirs.

Every config is in the config file, but its still happening

 

[Ajaja]

Every config is in the config file, but its still happening

Are all kernel files (jup230.bsp, sat252s.bsp,ura083.bsp,...) in Kernels directory?

 

[toodoo213]

Are all kernel files (jup230.bsp, sat252s.bsp,ura083.bsp,...) in Kernels directory?

actually in i've never got these bsp files from the kernels directory, I only got the for_kernels_file Text Document.

the only files

are

config-
all planets .cfg

doc - spice

kernels, one text doc with nothing written

modules - spice

source - 2 files

i have spice v03

 

[Ajaja]

toodoo213
This is module with few samples, but not complete Solar System addon. Your need download *.bsp files manualy.

 

[toodoo213]

toodoo213
This is module with few samples, but not complete Solar System addon. Your need download *.bsp files manualy.

oooooooooooooooooooohhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh!
thanx alot ajaja! :rofl:

 

[Chode]

Going back to an earlier topic, the EPHEM_PARENTBARY problem has been fixed in the latest beta version of Orbiter, so the next public versions should work as expected.

Regards

 

[Ajaja]

[deleted]

 

[flytandem]

Thanks.
I downloaded and extracted the files from the zip file into my orbiter folder. Nothing became obviousas to what to do to get Phoebe into Orbiter. I found the Phoebe cfg file and place a copy into the Config folder. And then edited the sol.cfg manually to place a line showing Phoebe as the next moon for Saturn. Phoebe then showed up but it had an unrealistic orbit with it starting out with such litte velocity that it fell directly into Saturn. It talks about a "module" names spice. How does one utilize it.?
rob

 

[Ajaja]

Thanks.
I downloaded and extracted the files from the zip file into my orbiter folder. Nothing became obviousas to what to do to get Phoebe into Orbiter. I found the Phoebe cfg file and place a copy into the Config folder. And then edited the sol.cfg manually to place a line showing Phoebe as the next moon for Saturn. Phoebe then showed up but it had an unrealistic orbit with it starting out with such litte velocity that it fell directly into Saturn. It talks about a "module" names spice. How does one utilize it.?
rob

You need to download ftp://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/satellites/a_old_versions/sat252s.bsp ant put it into Kernels folder. There is also new ephemeris file for Saturn moons in ftp://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/satellites/sat317.bsp , so you can download new one and change Phoebe.cfg to use this kernel.

 

[flytandem]

Thanks. There is currently no kernels folder in my Orbiter folder. Am I supposed to create it? The rest seem greek to me.
This is reminding me of when I was trying to get a multistage craft going last year. It took atuhalpa to actually send me a disk with it all working. If it's not with the stock Orbiter base package, then I am not likely able to get it to work.