  We present a final summary of all ROSAT X-ray observations of nearby stars.
All available ROSAT observations with the ROSAT PSPC, HRI and WFC have been
matched with the CNS4 catalog of nearby stars and the results gathered in the
Nearby X-ray and XUV-emitting Stars data base, available via www from the Home
Page of the Hamburger Sternwarte at
http://www.hs.uni-hamburg.de/DE/For/Gal/Xgroup/nexxus. New volume-limited
samples of F/G-stars (d_lim = 14 pc), K-stars (d_lim = 12 pc), and M-stars
(d_lim = 6 pc) are constructed within which detection rates of more than 90 %
are obtained; only one star (GJ 1002) remains undetected in a pointed follow-up
observation. F/G-stars, K-stars and M-stars have indistinguishable surface
X-ray flux distributions, and the lower envelope of the observed distribution
at F_X \approx 10^4 erg/cm^2/sec is the X-ray flux level observed in solar
coronal holes. Large amplitude variations in X-ray flux are uncommon for
solar-like stars, but maybe more common for stars near the bottom of the main
sequence; a large amplitude flare is reported for the M star LHS 288. Long term
X-ray light curves are presented for Alpha Cen A/B and Gl~86, showing
variations on time scales of weeks and demonstrating that Alpha Cen B is a
flare star.
