We report the discovery that the star V474 Car is an extremely active , high velocity halo RS CVn system .
The star was originally identified as a possible pre-main sequence star in Carina , given its enhanced stellar activity , rapid rotation ( 10.3 days ) , enhanced Li , and absolute magnitude that places it above the main sequence .
However , its extreme radial velocity ( 264 km s ^ { -1 } ) suggested that this system was unlike any previously known pre-MS system .
Our detailed spectroscopic analysis of echelle spectra taken with the CTIO 4-m finds that V474 Car is both a spectroscopic binary with orbital period similar to the photometric rotation period , and metal poor ( [ Fe/H ] \simeq - 0.99 ) .
The star ’ s Galactic orbit is extremely eccentric ( e \simeq 0.93 ) with perigalacticon of only \sim 0.3 kpc of the Galactic center - and its eccentricity and smallness of its perigalacticon are only surpassed by \sim 0.05 % of local F/G-type field stars .
The observed characteristics are consistent with V474 Car being a high velocity , metal poor , tidally-locked chromospherically active binary ( CAB ) , i.e .
a halo RS CVn binary , and one of only a few such specimens known .