HIP-60350 - AN EXTREME RUNAWAY STAR

Using Hipparcos proper motion as well as published and our own radial velocity data we identify HIP 60350 as fastest young B-type runaway st ar ejected 20 Myr ago or slightly less from the galactic plane, probab ly at a distance from the galactic center corresponding to spiral arm -II. Both the LSR velocity (417 kms(-1)) and the mass of the star poin t to dynamical cluster ejection rather than to a supernova scenario. P ublished and our own photometric data as well as our spectroscopic evi dence reveal no noticeable peculiarity and a spectral type B4/5 V. No significant radial velocity variations have been found during the last two decades.