Kinematic signatures of violent formation of galactic OB associations from Hipparcos measurements

Proper motions measured by Hipparcos confirm the large anomalous velocities of the OB associations located around the Cygnus Superbubble (Cygnus OB1, OB3, OB7, and OB9), and reveal a clearly organized expanding pattern in Canis Major OB1. At the distances of these associations, the organized velocity patterns imply LSR velocities of up to ∼ 60 km s−1 for… CONTINUE READING