stars.txt

Discussion forum for Celestia developers; topics may only be started by members of the developers group, but anyone can post replies.
Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #101by Cham » 18.10.2007, 17:09

t00fri wrote:So I propose I will arbitrarily kick out the doubled systems determined with the spectroscopic method.


I agree with this choice. Makes sense to me.

I suggest that you keep the spectroscopic doubles in the STC file : just add the # to comment them out.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

ElChristou
Developer
Posts: 3776
Joined: 04.02.2005
With us: 19 years 9 months

Post #102by ElChristou » 18.10.2007, 17:15

t00fri wrote:Actually, I also had a second look and I tend to agree that on the long run, we should find a better way to support an alternative or simultaneous display of such binary orbit data from different methods.

While the naming distinction is fine, it is disturbing that one always sees more than the correct number of stars in orbit.

I think we will have to continue being creative as concerns possibilities to intuitively visualizing measurement uncertainties in Celestia! In my opinion it is a really important challenge to come up with a neat solution here.

Clearly this double display of 'spc' and 'vis' based orbits is interesting for astronomers, since it is really not clear which orbit aspects are most affected by particular parameter uncertainties.

On the other hand for less serious applications this is clearly a suboptimal choice.

So I propose I will arbitrarily kick out the doubled systems determined with the spectroscopic method.

Bye Fridger


Then why not removing from both catalogues the problematic entries and create an "Uncertain Binaries Catalogue" containing those ones (with the naming convention by Cham)?
We lose nothing, we have some clear basic catalogues and if one need to visualize those uncertainties, he can add the 3rd catalogue in his extras...
Image

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #103by Cham » 18.10.2007, 17:26

ElChristou wrote:Then why not removing from both catalogues the problematic entries and create an "Uncertain Binaries Catalogue" containing those ones (with the naming convention by Cham)?


No, no ! They aren't "uncertain". It's just that both methods gives some small variations in the parameters, which is perfectly normal (any measurements have some uncertainties). It would be the same for all the others too. We should keep one of the two methods, as suggested by Fridger, with an uniformization of the names.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

Avatar
Topic author
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #104by t00fri » 18.10.2007, 17:38

ElChristou wrote:Then why not removing from both catalogues the problematic entries and create an "Uncertain Binaries Catalogue" containing those ones (with the naming convention by Cham)?
We lose nothing, we have some clear basic catalogues and if one need to visualize those uncertainties, he can add the 3rd catalogue in his extras...


But Christophe,

this would be entirely misleading. Those binary systems that Cham found to be doubled in visualbins and spectbins are actually on a better footing as to uncertainties than all the non-doubled ones!

Only in these few cases, we have a direct check about the physical parameter uncertainties due to these completely different methods being applied to the SAME binary systems.

So definitely we don't want to call these "Uncertain binaries". Why do you people keep having problems with the fact that ALL binary orbits are uncertain. The only question is by HOW MUCH?

This is an entirely normal and intrinsically unavoidable fact!

Even the length of the "m??tre des archives de 1889" (in Paris next to Mona L. ) is uncertain. Voil? !!

Bye Fridger
Image

ElChristou
Developer
Posts: 3776
Joined: 04.02.2005
With us: 19 years 9 months

Post #105by ElChristou » 18.10.2007, 18:36

Ok, ok, the term wasn't right...

In any case as I'm not qualified I shut up :oops:
(After all I'm sure you will chose the right solution... :wink:)
Image

chris
Site Admin
Posts: 4211
Joined: 28.01.2002
With us: 22 years 9 months
Location: Seattle, Washington, USA

Post #106by chris » 18.10.2007, 19:35

Cham wrote:
t00fri wrote:So I propose I will arbitrarily kick out the doubled systems determined with the spectroscopic method.

I agree with this choice. Makes sense to me.

I suggest that you keep the spectroscopic doubles in the STC file : just add the # to comment them out.


I'm coming to this discussion late because I'm away from home tending to some family matters. But, I think that the above compromise is a very reasonable one for the time being. After 1.5.0, we can find a better approach. Making it possible to load add-ons during a Celestia session (instead of just at the beginning) would allow users to choose either spectroscopic or visual binary catalogs. There will inevitably be overlap between different star catalogs, so it would be nice to have a general priority scheme to handle conflicts.

--Chris

Avatar
Topic author
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #107by t00fri » 18.10.2007, 19:49

Hi all,

please examine my changes for visualbins.stc and spectbins.stc!

This is what I modified in the two respective PERL scripts:

1) visualbins.pl
==========

Code: Select all

   $alt{$hip,'AB'} =~s/KSI/XI/g;
   $alt{$hip,'A'}  =~s/KSI/XI/g;
   $alt{$hip,'B'}  =~s/KSI/XI/g;

replacing KSI -> XI

Code: Select all

if(/Dec\b\s+([-\d.]+)/){$c2 = $1; next;}

which corrects the parameters of XI Sco.
There was a bug for negative Dec! Also there is a spectral class now!

2) spectbins.pl
=========

Code: Select all

   # eliminate certain binaries that are already in visualbins.stc
   # List due to Martin Charest
   next if ($hip =~ /89937/); # Chi Dra
   next if ($hip =~ /12390/); # Eps Cet
   next if ($hip =~ /20087/); #  51 Tau
   next if ($hip =~ /38382/); #   9 Pup
   next if ($hip =~ /7580/);  # Kui 7 
   next if ($hip =~ /20661/); # Fin 342
   next if ($hip =~ /2941/);  # ADS 520
   next if ($hip =~ /111528/);# ADS 16098
   next if ($hip =~ /45170/); # Fin 347Aa
   next if ($hip =~ /75312/); # ETA CrB
   next if ($hip =~ /85667/); # SIG 2173
   next if ($hip =~ /87895/); # HR 6697
   next if ($hip =~ /95995/); # Gl 762.1
   next if ($hip =~ /98416/); # Gl 773.3
   next if ($hip =~ /99376/); # ADS 13461


This kicks out the doubles found by Martin. Sorry I was too lazy to make the PERL script comment out the respective data. Just kicked them out for now.

Code: Select all

   $alt{$hip,'AB'} =~s/KHI/CHI/g;
   $alt{$hip,'A'}  =~s/KHI/CHI/g;
   $alt{$hip,'B'}  =~s/KHI/CHI/g;

   $alt{$hip,'AB'} =~s/KSI/XI/g;
   $alt{$hip,'A'}  =~s/KSI/XI/g;
   $alt{$hip,'B'}  =~s/KSI/XI/g;


Replaces eventual KHI -> CHI; KSI -> XI

Actually, Martin, you had a typo in your list:

The double was SIG 2173 NOT SIG 2174.

Here are the PERL scripts

http://www.celestiaproject.net/~t00fri/images/ ... ins.pl.zip
http://www.celestiaproject.net/~t00fri/images/spectbins.pl.zip

and generated .stc files for download and testing:

http://www.celestiaproject.net/~t00fri/images/visualbins.stc
http://www.celestiaproject.net/~t00fri/images/spectbins.stc

Let me know....

Bye Fridger
Image

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #108by Cham » 18.10.2007, 20:05

Great ! Thanks Fridger.

I'm in my office right now. I'll test your new files later today, when I'll be back home (in few hours).

-M.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

Avatar
Topic author
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #109by t00fri » 18.10.2007, 20:10

On this occasion of people staring at binary orbits I want to remind everyone again how UNPHYSICAL the orbit drawing is presently in frames where component A or B is at rest and component B or A, respectively encircles it!

This bad display is due to the inappropriate assumption that SENSIBLE orbit renderings are frame independent. ;-) (why should they?)

Bye Fridger
Last edited by t00fri on 18.10.2007, 21:48, edited 1 time in total.
Image

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #110by Cham » 18.10.2007, 20:36

Fridger,

is it possible to add all the names (from the various catalogs) for each star, like this below ?

Code: Select all

"70 Tau:Fin 342"
"HIP2941:ADS 520"
"HIP98416:Gl 773.3"

instead of this :

Code: Select all

"70 Tau"
"HIP2941"
"HIP98416"


I made something similar with my pulsars addon, so we can use all the name conventions to find a particular object (PSR J2000, PSR B1950, ...).
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

Avatar
Topic author
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #111by t00fri » 18.10.2007, 21:01

Cham wrote:Fridger,

is it possible to add all the names (from the various catalogs) for each star, like this below ?

Code: Select all

"70 Tau:Fin 342"
"HIP2941:ADS 520"
"HIP98416:Gl 773.3"

instead of this :

Code: Select all

"70 Tau"
"HIP2941"
"HIP98416"


I made something similar with my pulsars addon, so we can use all the name conventions to find a particular object (PSR J2000, PSR B1950, ...).


Martin,

everything is possible, of course, but this is a lot of work, really. Since the name lists come from different (published) catalogs, I would have to rewrite my PERL script substantially. Many of those additional names are not really familiar ones and hence I don't think this is worth the effort. Note that for each star there are many more names in the Simbad data base!

Bye Fridger
Image

Avatar
Topic author
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #112by t00fri » 18.10.2007, 21:09

Hi all,

Fridger wrote:Sorry I was too lazy to make the PERL script comment out the respective data. Just kicked them out for now.


Since I am not really the "lazy type" ;-) I could finally not resist to modify my PERL scripts such that they now comment out ALL the binaries that either appear in the partner binary catalog OR in Grant's nearstars.stc catalog. So now visualbins.stc and specbins.stc contain the FULL published databases, with some redoubled binaries commented out!

This allows people to experiment with the various orbit parameters, which really is the best present compromise.


Here are again the download URL's:

the modified PERL scripts

http://www.celestiaproject.net/~t00fri/images/ ... ins.pl.zip
http://www.celestiaproject.net/~t00fri/images/spectbins.pl.zip

and generated .stc files for download and testing:

http://www.celestiaproject.net/~t00fri/images/visualbins.stc
http://www.celestiaproject.net/~t00fri/images/spectbins.stc

Let me know....

Bye Fridger
Last edited by t00fri on 19.10.2007, 21:21, edited 1 time in total.
Image

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #113by Cham » 18.10.2007, 22:30

Fridger,

I'm testing your latest files (from the previous message). Until now, everything appears to be fine.

I need some clarification on the HIP numbering convention : in your visual binaries file, all HIP numbers don't have a space in the name. For example : HIP2237, instead of HIP 2237. I always assumed the usage was to put a space after the HIP prefixe. Am I right ?

Really, there's something I don't understand about the HIP numbering convention.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

Avatar
Topic author
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #114by t00fri » 18.10.2007, 22:48

Well this is from the original papers. But I agree we should make it the same everywhere in Celestia. It's no problem. I'll do it once you have finished testing in this round.

Bye Fridger
Image

ElChristou
Developer
Posts: 3776
Joined: 04.02.2005
With us: 19 years 9 months

Post #115by ElChristou » 18.10.2007, 22:49

Fridger, a small irrelevant detail: would it be possible to change the names of those 2 files to something like: bin_visu.stc and bin_spect.stc? (it's a way to keep the two files grouped while sorted by name in the data directory)
Image

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #116by Cham » 18.10.2007, 22:52

ElChristou wrote:Fridger, a small irrelevant detail: would it be possible to change the names of those 2 files to something like: bin_visu.stc and bin_spect.stc? (it's a way to keep the two files grouped while sorted by name in the data directory)


Oh, yes, I agree with this.

But don't forget to edit your config file ! Both STC files are declared in there.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"

ElChristou
Developer
Posts: 3776
Joined: 04.02.2005
With us: 19 years 9 months

Post #117by ElChristou » 18.10.2007, 22:57

Cham wrote:...But don't forget to edit your config file ! Both STC files are declared in there.


Oops, forgot this detail... yes, else nothing on screen!
Image

Avatar
Topic author
t00fri
Developer
Posts: 8772
Joined: 29.03.2002
Age: 22
With us: 22 years 7 months
Location: Hamburg, Germany

Post #118by t00fri » 18.10.2007, 22:59

Well I see the point but these alternative names are not nice. Also it's quite a few manipulations to delete and reenter new files in CVS. So this should really be motivated.

Changing filenames 2 years after they have been added to the distribution is not the best of all ideas.
For instance, this means changing the names on my 4 computers at 16 places , in all my perlscripts in CVS , changing the perlscript names etc!

Bye Fridger
Image

ElChristou
Developer
Posts: 3776
Joined: 04.02.2005
With us: 19 years 9 months

Post #119by ElChristou » 18.10.2007, 23:07

t00fri wrote:Well I see the point but these alternative names are not nice. Also it's quite a few manipulations to delete and reenter new files in CVS. So this should really be motivated.

Changing filenames 2 years after they have been added to the distribution is not the best of all ideas.
For instance, this means changing the names on my 4 computers at 16 places , in all my perlscripts in CVS , changing the perlscript names etc!

Bye Fridger


No way to write a PERL script to change all the names? :D
(No I was kidding, forget, it's not important...)
Image

Avatar
Cham M
Posts: 4324
Joined: 14.01.2004
Age: 60
With us: 20 years 10 months
Location: Montreal

Post #120by Cham » 18.10.2007, 23:13

ElC,

in this case, just edit your config file. This is to the user's discretion, like many other options we have. For example, I've already edited the config file to use a CELX start script instead of the usual CEL start script, so I can use several custom commands in Celestia. I've also edited the solarsys.ssc file to change lots of textures, asteroids models, etc. We can do the same with the config file and the names of some data files too.
"Well! I've often seen a cat without a grin", thought Alice; "but a grin without a cat! It's the most curious thing I ever saw in all my life!"


Return to “Ideas & News”