Quadruple system STC check

[Malenfant]

Here's another fictional star system for people to take a look at - this one is a quadruple consisting of two M1Vs in close orbit around eachother, with two M0Vs in separate orbits further away. If you have 1.5.0 you can see the barycentre orbits too. The orbital distances etc are calculated realistically beforehand. You can get a good overview of it by using the "Goto Object" option for "QuadABCD" and going to lat 90, lon 0, distance of 700 AU - that puts you above the system where you can see the orbits.

This system looks a bit odd and unlikely to me though - I think it's the way that the orbits themselves don't seem to change orientation over time. Can anyone spot any obvious flaws with it?

Code: Select all

Barycenter "QuadABCD"
{
RA         45
Dec        45
Distance  110
}

#effective mass of (S+C) binary barycentre=0.883 solar masses
#effective mass of (S+C)+N1 barycentre=1.254 solar masses
#effective mass of (S+C)+N1+N2 barycentre=1.648 solar masses

#-----------
Barycenter "QuadABC"
{
   OrbitBarycenter "QuadABCD"

   EllipticalOrbit {             
      Period          1281.118
      SemiMajorAxis   33.279
      Eccentricity    0.74052
      ArgOfPericenter 0
   }
}

"Quad4"
{
OrbitBarycenter "QuadABCD"
SpectralType "M1V"
AbsMag  9.25 # Luminosity = 0.018 Sol, mass=0.208
Radius 307296

   EllipticalOrbit {               
      Period          1281.118
      SemiMajorAxis   106.041
      Eccentricity    0.74052
      ArgOfPericenter 180
   }
}

#-----------
Barycenter "QuadAB"
{
   OrbitBarycenter "QuadABC"

   EllipticalOrbit {             
      Period          88.484
      SemiMajorAxis   6.337
      Eccentricity    0.87831
      ArgOfPericenter 0
   }
}

"Quad3"
{
OrbitBarycenter "QuadABC"
SpectralType "M1V"
AbsMag  9.5 # Luminosity = 0.018 Sol, mass=0.208
Radius 257296

   EllipticalOrbit {               
      Period          88.464
      SemiMajorAxis   15.077
      Eccentricity    0.87831
      ArgOfPericenter 180
   }
}

#-----------
"Quad1"
{
OrbitBarycenter "QuadAB"
SpectralType "M0V"
AbsMag  8.7 # Luminosity = 0.031 Sol, mass=0.446
Radius 382000

   EllipticalOrbit {             
      Period          0.292
      SemiMajorAxis   0.209
      Eccentricity    0.3562
      ArgOfPericenter 0
   }
}

"Quad2"
{
OrbitBarycenter "QuadAB"
SpectralType "M0V"
AbsMag  8.75 # Luminosity = 0.029 Sol, mass=0.437
Radius 378000

   EllipticalOrbit {             
      Period          0.292
      SemiMajorAxis   0.214
      Eccentricity    0.3562
      ArgOfPericenter 180
   }
}

#-------------


#  506 0.35620     0.422     0.209     0.214     0.068     0.067     1.402         0.292          (S+C)
#  506 0.87831    21.413     6.337    15.077     0.432     0.274    92.975        88.484       (S+C)+N1
#  506 0.74052   139.320    33.279   106.041     9.186     5.211   590.984      1281.118    (S+C)+N1+N2
#
#   506 M0   5  0.446  3825.     0.0311688     0.403   3558000128.   1   2  17
#   506 M0   5  0.437  3805.     0.0293278     0.395   3558000128.   1   2  17
#   506 M1   5  0.371  3664.     0.0182237     0.336   3558000128.   1   2  17
#   506 M1   5  0.394  3717.     0.0221441     0.360   3558000128.   1   2  17
 

[Cham]

Malenfant,

can you confirm that bug about stars orbit not showing at some distance (using the CVS version of Celestia 1.5.0) ? When I visit your quad system, I can only see the orbits if I'm pretty close. But as soon as I move back (few AU from the barycenters), the orbits disappears.

[chris]

Malenfant,

can you confirm that bug about stars orbit not showing at some distance (using the CVS version of Celestia 1.5.0) ? When I visit your quad system, I can only see the orbits if I'm pretty close. But as soon as I move back (few AU from the barycenters), the orbits disappears.

That's not a bug, it's intended behavior. In order to avoid cluttering the display with orbits, they're only shown when they're larger than a certain size on screen. I plan on making this threshold size configurable, but it's currently fixed at 20 pixels.

--Chris

[Cham]

That's not a bug, it's intended behavior. In order to avoid cluttering the display with orbits, they're only shown when they're larger than a certain size on screen. I plan on making this threshold size configurable, but it's currently fixed at 20 pixels.

20 pixels ? I'm not sure we're talking about the same thing here.

I'm unable to properly see the orbits of all that quad system globally at once. If I get too far away (not that much), the orbits disappears, I mean all of them at once. I'm unable to have a global view.

For example, use that URL :

cel://Follow/StarS/2004-01-08T06:07:13. ... 44535&lm=2

Just move back and all the orbits are disappearing suddenly.

[selden]

Cham,

I think this is the same driver bug that you've been fighting with in other circumstances

Here's what I see:


The top half is your url.
The bottom half is backed off to see the overview of the system.

There's a dashed effect in the orbit paths caused by 4x antialiasing

System:
512MB 2.4GHz P4, WinXP Pro SP2
128MB FX5200, ForceWare v91.31
Celesta from CVS this morning

[Cham]

ahaa !

So there's a bug !

I'm unable to reproduce your bottom view. Orbits can't be seen.

[Malenfant]

I can see the stars when I move back too. However, I've noticed two things:

1) the orbit lines for the stars go partly and then mostly cyan in colour
(instead of blue) when I get closer from that Cel URL that Cham posted. (I
move closer and further by using the scroll wheel on my mouse). The
colour change seems to occur when the star flares turn themselves on again when I get close enough.

2) I have another star called StarS loaded into Celestia, in my Trinary
addon. The version of 1.5.0 that I have seems to get confused by this -
the view from that cel URL was set to follow StarS, and it followed the one
in the other system, not this one! It doesn't seem to be recognising that
the other StarS is in a completely different system anymore. Has anyone
else noticed this sort of thing?

To test it, try adding a planet with the same name as an existing one in
another system. Go to one of those systems, and then see what happens
when you try to lock onto one of the identically-named planets.

[Cham]

The
colour change seems to occur when the star flares turn themselves on again when I get close enough.

I noticed a similar correlation between stars orbit disappearing and star glare texture. I strongly feel the bug I'm describing (orbits disappearing) isn't a driver bug. It's in the CVS code.

[Malenfant]

I think I found a bug with this addon... posted to the Bugs board:
http://www.celestiaproject.net/forum/viewtopic.php?t=10170

[Malenfant]

I think I'm doing something wrong here, and that this isn't a bug, but I'd
like someone to check it anyway please...

I added some more asteroid orbits here - however, ABlimitS1 and
ABlimitS2 don't appear to be selectable when you hit "Enter" in Celestia
(they don't show up when you start typing "AB...").

It seems related to where you are. if I Goto QuadAB, then LimitS2 and
LimitP show up on the target list, but LimitS1 doesn't.

But if I Goto Quad1, then LimitS1 and LimitS2 show up but LimitP doesn't.

And if I Goto QuadABC, then ABlimitP and LimitS2 show on the target list,
but LimitS1 doesn't.

What I'd like to be able to do is to go to QuadAB and be able to target
LimitS1, LimitS2, and LimitP, which are all orbits associated with that
barycentre (they represent the limit at which planets can form around
each star or the barycentre). So basically, if I select a barycentre then I
should be able to select/target any of its children (or things orbiting its
children). Is there a way to do this?


Here's the code...

Code: Select all

"limitS1" "Quad1"
{
Radius 10

EllipticalOrbit {
Period 1
SemiMajorAxis 0.068
Eccentricity 0.00
Inclination 0.00
AscendingNode 0.0
LongOfPericenter 0.0
MeanAnomaly 0.0
}

Albedo 0.30
}


"limitS2" "Quad2"
{
Radius 10

EllipticalOrbit {
Period 1
SemiMajorAxis 0.067
Eccentricity 0.00
Inclination 0.00
AscendingNode 0.0
LongOfPericenter 0.0
MeanAnomaly 0.0
}

Albedo 0.30
}

"limitP" "QuadAB"
{
Radius 10

EllipticalOrbit {
Period 1
SemiMajorAxis 1.402
Eccentricity 0.00
Inclination 0.00
AscendingNode 0.0
LongOfPericenter 0.0
MeanAnomaly 0.0
}

Albedo 0.30
}

#----------------

"ABlimitS1" "QuadAB"
{
Radius 10

EllipticalOrbit {
Period 1
SemiMajorAxis 0.432
Eccentricity 0.00
Inclination 0.00
AscendingNode 0.0
LongOfPericenter 0.0
MeanAnomaly 0.0
}

Albedo 0.30
}


"ABlimitS2" "Quad3"
{
Radius 10

EllipticalOrbit {
Period 1
SemiMajorAxis 0.274
Eccentricity 0.00
Inclination 0.00
AscendingNode 0.0
LongOfPericenter 0.0
MeanAnomaly 0.0
}

Albedo 0.30
}

"ABlimitP" "QuadABC"
{
Radius 10

EllipticalOrbit {
Period 1
SemiMajorAxis 92.975
Eccentricity 0.00
Inclination 0.00
AscendingNode 0.0
LongOfPericenter 0.0
MeanAnomaly 0.0
}

Albedo 0.30
}


[chris]

Celestia considers only the closest star or selected star as the scope for planet name completion. You'll have to use the full name of the objects to select them, e.g. QuadAB/limitP instead of just limitP

--Chris

[Malenfant]

Celestia considers only the closest star or selected star as the scope for planet name completion. You'll have to use the full name of the objects to select them, e.g. QuadAB/limitP instead of just limitP

--Chris

That seems awfully clunky though, and while that might have worked fine for
individual stars and planets it doesn't work well for barycentres. Why not
have it so that Celestia considers all the descendents of the currently
selected object as the scope for planet name completion instead? (plus,
that way you can go to Sol and then be able to select a moon of a planet
in the solar system, and not just the planets). That still keeps things local,
but not annoyingly restrictive. It'd surely be easier to code too.

And also, that doesn't seem to be implemented consistently anyway. If I
select Quad1, then I should only be able to see LimitS1 (around Quad1) only,
shouldn't I? So why can I see LimitS1 and LimitS2 (which is around Quad2)
on the list when I select Quad1?

[chris]

Celestia considers only the closest star or selected star as the scope for planet name completion. You'll have to use the full name of the objects to select them, e.g. QuadAB/limitP instead of just limitP

--Chris

That seems awfully clunky though, and while that might have worked fine for
individual stars and planets it doesn't work well for barycentres. Why not
have it so that Celestia considers all the descendents of the currently
selected object as the scope for planet name completion instead? (plus,
that way you can go to Sol and then be able to select a moon of a planet
in the solar system, and not just the planets). That still keeps things local,
but not annoyingly restrictive. It'd surely be easier to code too.

It's not easier to code than not changing anything at all. I agree that selection by name could be done better with regard to multiple star systems, but it's a low priority for me right now.

--Chris