gaia clusters

[selden]

A paper has been published which discusses the improvement in determining memberships of various Open Clusters when using Gaia data.

See http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query? ... ..19G&db_key=AST&nosetcookie=1

I've created a Celestia Addon which can be used to view the clusters and their memberships.

It's available at https://www.classe.cornell.edu/~seb/celestia/files/gaia_clusters.zip (8 MB, expands to 10.5 MB)

Here's a screengrab showing Open Cluster members as described in the paper:

Gaia cluster members

For comparison, here's a picture taken from the same viewpoint using previously published cluster memberships which had been determined using pre-Gaia data.

Pre-Gaia cluster members

The use of Gaia data produces results which are greatly improved for clusters which are reasonably close to us, but the kinematics and positions for more distant clusters obviously have room for improvement.

[john71]

Thank you! Excellent!

[selden]

I located a pre-Gaia study of the Hyades cluster on Vizier: J/A+A/367/111 A Hipparcos study of the Hyades cluster (de Bruijne+, 2001) and combined it with WebDA's membership probabilities to produce the picture below.

de Bruijne members are colored green and red, Webda lignt and dark blue. Again, these use Gaia star locations. Only the selections differ.

I revised the Addon to include scripts to mark those stars.

https://www.classe.cornell.edu/~seb/celestia/files/gaia_clusters_v2.zip

[selden]

Gaia DR2: A93_open_clusters.zip
(20 MB, expands to 25 MB, 24Nov18)

This Addon for Celestia v1.6.1 or later includes catalogs of 1,229 Open Clusters and 397,897 of their member stars, as provided by

"J/A+A/618/A93 Gaia DR2 open clusters in the Milky Way (Cantat-Gaudin+, 2018)" (downloaded from VizieR).

Before installing this Addon, you should uninstall the previous Gaia DR1 cluster addon.

This Addon does not include the Hyades cluster or any of its members.

The screengrab below shows the Pleiades cluster with its stars marked. When Celestia starts, it's currently hidden behind the Earth.

[john71]

Thank you!