V501 Her is a well detached G3 eclipsing binary star with a period of
8.597687 days for which we have determined very accurate light and
radial-velocity curves by using robotic telescopes. Results of these data
indicate that the component stars have masses of 1.269 +/- 0.004 and 1.211 +/-
0.003 solar masses, radii of 2.001 +/- 0.003 and 1.511 +/- 0.003 solar radii,
and temperatures of 5683 +/- 100K and 5720 +/- 100K, respectively. Comparison
with the Yonsei-Yale series of evolutionary models results in good agreement at
an age of about 5.1 Gyr for a somewhat metal rich composition. Those models
indicate that the more massive, larger, slightly cooler star is just beyond
core hydrogen exhaustion while the less massive, smaller, slightly hotter star
has not quite reached core hydrogen exhaustion. The orbit is not yet
circularized, and the components are rotating at or near their
pseudosynchronous velocities. The distance to the system is 420 +/- 30 pc
