Explore Galactic Structure Using Star Clusters
Star clusters are divided up between open star clusters, relatively young and random groups, and globular star clusters, typically older groups with a roughly spherical distribution.
As a reference point, you can query for the position of the center of the Milky Way with respect to the Sun.
In a similar fashion, you need to get the positions of the various star clusters.
For fitting and plotting in graphics, you need only magnitude, in light years, of the various quantities.
Open clusters are found in the galactic disk/plane, so you can use the coordinates of the open star clusters to fit this to a plane.