Updated version of charm2.stc

The place to discuss creating, porting and modifying Celestia's source code.
Avatar
Topic author
LukeCEL
Posts: 187
Joined: 26.09.2017
With us: 1 year 9 months

Updated version of charm2.stc

Post #1by LukeCEL » 03.11.2018, 21:26

Hi everyone. The new thread by onetwothree about restarting the development of Celestia re-kindled my interest in updating the star catalogs of Celestia. In particular, one thing that might be easy to do is charm2.stc, which is a catalog of stellar radii using measurements of stellar angular size. Anyway, CHARM2 was published in 2005 and since then, there have been many new catalogs that I could use for the apparent diameters—not to mention Gaia DR2, which provides the distances which are needed to convert the apparent diameter to a real diameter.

On VizieR there's a list of options—just select "Diameters" in the scroll-down menu for Astronomy, then click Find Catalogs for the list. Do you have any suggestions for which one I should use? If not I'll just use CHARM2 and try to update that using Gaia DR2.

Avatar
SpaceFanatic64
Posts: 330
Joined: 16.08.2018
Age: 13
With us: 11 months 2 days
Location: Southern California

Post #2by SpaceFanatic64 » 03.11.2018, 22:51

Luke, it would also be cool if visualbins and spectbins were updated to have your Binary Star Catalog addon.
Follower of the "Celestia Origin" project
Graphics Card: ATI Radeon 3000 Graphics

Avatar
selden
Developer
Posts: 10053
Joined: 04.09.2002
With us: 16 years 10 months
Location: NY, USA

Post #3by selden » 03.11.2018, 22:51

So long as you choose a specific catalog, specify what it is and document all of the changes you make, I think it should be fine.

Ideally, anyone should be able to follow the same procedure you did and get the same results.
Selden

Avatar
Topic author
LukeCEL
Posts: 187
Joined: 26.09.2017
With us: 1 year 9 months

Post #4by LukeCEL » 04.11.2018, 12:52

SpaceFanatic64 wrote:Luke, it would also be cool if visualbins and spectbins were updated to have your Binary Star Catalog addon.

I'm actually considering updating visualbins.stc with a data from Cvetković et al. (2010). It's going to take a while, though, since I'd have to extract orbits from the Sixth Orbit Catalogue. If anybody knows of any more data sources that I could use, please send them my way.

selden wrote:So long as you choose a specific catalog, specify what it is and document all of the changes you make, I think it should be fine.

Okay, thank you. My first choice was to use the JMMC Stellar Diameters Catalog v2, which is a massive catalog that my measly computer can't handle. It's going to be harder than I thought...

Avatar
SpaceFanatic64
Posts: 330
Joined: 16.08.2018
Age: 13
With us: 11 months 2 days
Location: Southern California

Post #5by SpaceFanatic64 » 04.11.2018, 18:18

Luke, can you create an STC code that modifies Rigel and Spica as binary stars?
Follower of the "Celestia Origin" project
Graphics Card: ATI Radeon 3000 Graphics

Avatar
Joey P. M
Posts: 150
Joined: 28.10.2017
Age: 16
With us: 1 year 8 months
Location: Vladivostok, Russia

Post #6by Joey P. » 04.11.2018, 19:04

Charm2 is wildly inaccurate and obsolete. Definitely needs an update. Thanks.
Joey P.

Avatar
Askaniy M
Posts: 43
Joined: 17.09.2017
With us: 1 year 10 months
Location: Saint Petersburg, Russia

Post #7by Askaniy » 11.11.2018, 11:41

LukeCEL, theoretically, can you create a full star catalog from scratch?

Avatar
Topic author
LukeCEL
Posts: 187
Joined: 26.09.2017
With us: 1 year 9 months

Post #8by LukeCEL » 11.11.2018, 15:43

Askaniy wrote:LukeCEL, theoretically, can you create a full star catalog from scratch?

I don't know how to create a stars.dat file. However, usually what I do to create a star catalog (in .stc) is I download some data from SIMBAD, copy and paste that data into Microsoft Excel, play around with that, copy and paste the new data into a text editor, and use find and replace to replace tabs with line breaks, etc. A full star catalog would be too much data for my computer to handle, but it might be possible to do in chunks.

Avatar
Topic author
LukeCEL
Posts: 187
Joined: 26.09.2017
With us: 1 year 9 months

Post #9by LukeCEL » 23.12.2018, 01:02

Hi everyone. I've created a preliminary version of jsdc.stc, a stellar radius catalog meant to supersede charm2.stc. It contains radii for 66,295 stars.

For these new star catalogs I'm trying to build them using Perl scripts to make my procedure easily reproducible. For more information, see LukeCEL/jsdc on GitHub. I've also re-worked buildstardb.pl to create an updated version of the stars.dat file.

For jsdc.stc, I've used the enormous JMMC Stellar Diameters Catalogue, and cross-matched it with the Hipparcos Catalogue using the CDS X-Match Service. Then I used a Perl script to extract the values, using stars.txt as the source of distances.

Here's the file. Any feedback is appreciated.
Attachments
jsdc.stc.zip
(926.49 KiB) Downloaded 17 times


Return to “Development”

Who is online

Users browsing this forum: 3 guests
Bots: Bing [Bot]