We present 1985-1988 UBV and VRI photometry obtained at three different observatories and analyze it along with previously published 1982-1984 UBV photometry. New times of midprimary eclipse along with previously published times yield the improved orbital ephemeris T(pri.min.)=JD 2446674.185(+/-0.007)+27.(d)53707(+/-0.d00026)n. Periodogram analysis of previously published radial velocities, for both the K giant and the F subgiant, yields orbital ephemeris constants consistent with the one above, but of lesser precision. Fitting the seven years of photometry with a cos(2 theta) curve, after removing the eclipse points, yields 0.(m)021+/-0.(m)006 for the full amplitude of the ellipticity effect in V. Residuals from that cos(2 theta) fit give light curves which reveal continuing starspot variability, which had been seen in the 1982-1984 photometry. These residuals, in ten data groups, are analyzed with a two-spot light-curve fitting procedure. Six long-lived spots are identified, the largest producing a light loss of 0.(m)166 in V. Lifetimes were >2.85, 0.81, 1.88, 1.84, >0.58, and >0.45 yr. Rotation periods for these six spots have a mean of 27.(d)36+/-0.(d)06, thus confirming synchronous rotation, and a range which indicates a differential rotation coefficient of k=0.031. With respect to the value of 0.65 below which strong dynamo action is expected in a convective star, the Rossby number for the K giant, believed to be the spotted star, is 0.17, well below the threshold and so large starspots are expected. (C) 1996 American Astronomical Society.

HD 30957 is a double-lined spectroscopic binary with a period of 44.395 days and a modest eccentricity of 0.09. The spectral types of the components are K2-3 V and K5 V. The measured v sin i for both components is less than or equal to 3 km s(-1) and the orbital inclination is estimated to be 69 degrees. The system is relatively nearby with a parallax of 0.025'' or a distance of 40 pc. Space motions of the system indicate that it does not belong to any of the known moving groups. Absolute surface fluxes of the Ca II H and K lines have been recomputed and indicate only modest chromospheric activity. If the stars are rotating pseudosynchronously, the lack of light variability is consistent with the value of the critical Rossby number for starspot activity.