  Contact binary stars are common variable stars which are all believed to emit
relatively large fluxes of x-rays. In this work we combine a large new sample
of contact binary stars derived from the ROTSE-I telescope with x-ray data from
the ROSAT All-Sky Survey (RASS) to estimate the x-ray volume emissivity of
contact binary stars in the galaxy. We obtained x-ray fluxes for 140 contact
binaries from the RASS, as well as 2 additional stars observed by the
XMM-Newton observatory. From these data we confirm the emission of x-rays from
all contact binary systems, with typical luminosities of approximately 1.0 x
10^30 erg s^-1. Combining calculated luminosities with an estimated contact
binary space density, we find that contact binaries do not have strong enough
x-ray emission to account for a significant portion of the galactic x-ray
background.
