Kinematic study of the association Cyg OB3 with Gaia DR2

Understand

We study the stellar kinematic properties and spatial distribution of the association Cyg OB3 using precise astrometric data from Gaia DR2.

• All known O- and B-type stars in Cyg OB3 region with positions, parallaxes and proper motions available are included, comprising a total of 41 stars.
• The majority of stars are found to be concentrated at a heliocentric distance of 2.0 +/- 0.3 kpc.
• The mean peculiar velocity of the sample after removing Galactic rotation and solar motion is ~22 km/s, dominated by the velocity component towards the Galactic center.