Saturday, November 24, 2018

Gaia DR2: Milky Way Open Clusters

Gaia's Data Release 2 provides improved positions for more than 1 billion (10^9) stars. The paper "A Gaia DR2 view of the open cluster population in the Milky Way." by T. Cantat-Gaudin, et al. (2018) uses that information to generate a catalog of more than 1,000 Open Clusters and about 400,000 of their member stars.

I've created an Addon for Celestia v1.6.1 and later, A93, which uses that paper's published catalog to provide the locations of 1,229 Open Clusters and 397,897 stars. It's available as https://www.classe.cornell.edu/seb/celestia/files/A93_open_clusters.zip (20MB, expands to 25MB).

Here's the Pleiades Cluster viewed from near the Earth.


Photo:

Wednesday, November 7, 2018


A revised version of Celestia's default stars.dat, containing 114357 stars, is available at https://www.classe.cornell.edu/~seb/celestia/files/simbad-hipparcos_v114.zip  (about 1.9 MB, expands to  2.2 MB).

The star positions were obtained from the Simbad astronomical database, which uses Gaia DR2 positions for most of its stars. Simbad is available at http://simbad.u-strasbg.fr/simbad/. For details about Gaia, see http://sci.esa.int/gaia/