GSoC/GCI Archive
Google Code-in 2012 KDE

Marble: Add more Southern Constellations to the Stars Plugin

completed by: Illya Kovalevskyy

mentors: Torsten Rahn, René Küttner, Dennis Nienhüser

During Google Code-In the Stars Plugin has been revamped and constellation lines as well as Deep Sky objects have been added.

 

This task is about adding more objects. Check out Marble's source code (http://marble.kde.org/sources.php will tell you how) and open the file

marble/data/stars/constellations.dat

namely the following ones:

  • Pavo ( with exactly these constellation lines: http://it.wikipedia.org/wiki/File:Pavo_constellation_map.png , don't add the line to Beta Indi)
  • Octans ( with exactly these constellation lines: http://en.wikipedia.org/wiki/File:Octans_IAU.svg )
  • Hydrus ( with exactly these constellation lines: http://en.wikipedia.org/wiki/File:Hydrus_IAU.svg )
  • Vela ( with exactly these constellation lines: http://en.wikipedia.org/wiki/File:Vela_IAU.svg - ommit the line to the constellation carina )
  • Carina ( with exactly these constellation lines: http://fr.wikipedia.org/wiki/Fichier:Carina_constellation_map-fr.png )
  • Puppis ( with exactly these constellation lines: http://fr.wikipedia.org/wiki/Poupe_%28constellation%29 )
  • Piscis Austrinus ( with exactly these constellation lines: http://it.wikipedia.org/wiki/File:Piscis_Austrinus_constellation_map.png )

 

Creating the constellation lines works like this: you look up the stars one by one that are part of the lines: In the constellation Centaurus ( http://de.wikipedia.org/w/index.php?title=Datei:Centaurus_constellation_map.png&filetimestamp=20041212180049, done in a previous task)  you could start of with the Star named Toliman which is "Alpha Centauri" or short "Alp Cen". Look up "Alp Cen" in the file

marble/tools/stars/catalog.dat

After some search it turns out there is no "Alp Cen" but "Alp1Cen" and "Alp2Cen" because Alpha Centauri is a double star. We take the brighter component (with the lower magnitude number which is +0.71 in this case). And we identify the first number in the catalog line which is "5459". The number "5459" is the number we need to enter into the constellations.dat filel Then we continue to do the same with the next star in the line: "Beta Centauri" ("Bet Cen") and find that the number at the start of the catalog line is 5267. etc. An index number "-1" is used to start a new line string.