Context : V1094 Tau is bright eclipsing binary star with an orbital period close to 9 days that contains two stars similar to the Sun .

Aims : Our aim is to test models of Sun-like stars using precise and accurate mass and radius measurements for both stars in V1094 Tau .

Methods : We present new spectroscopy of V1094 Tau , which we use to estimate the effective temperatures of both stars and to refine their spectroscopic orbits .
We also present new , high-quality photometry covering both eclipses of V1094 Tau in the Strömgren uvby system and in the Johnson V-band .

Results : The masses , radii , and effective temperatures of the stars in V1094 Tau are found to be M _ { A } = 1.0965 \pm 0.0040 M _ { \sun } , R _ { A } = 1.4109 \pm 0.0058 R _ { \sun } , T _ { eff,A } = 5850 \pm 100 K , M _ { B } = 1.0120 \pm 0.0028 M _ { \sun } , R _ { B } = 1.1063 \pm 0.0066 R _ { \sun } , and T _ { eff,B } = 5700 \pm 100 K. An analysis of the times of mid-eclipse and the radial velocity data reveals apsidal motion with a period of 14500 \pm 3700 years .

Conclusions : The observed masses , radii , and effective temperatures are consistent with stellar models for an age \approx 6 Gyr if the stars are assumed to have a metallicity similar to the Sun .
This estimate is in reasonable agreement with our estimate of the metallicity derived using Strömgren photometry and treating the binary as a single star ( [ Fe/H ] = -0.09 \pm 0.11 ) .
The rotation velocities of the stars suggest that V1094 Tau is close to the limit at which tidal interactions between the stars force them to rotate pseudo-synchronously with the orbital motion .