ABSTRACT. We present refined BVI light curves for six field RR Lyrae variable stars. The refinements include new data and improved photometric calibration compared to our previous work. For each star, we derive the intensity mean magnitudes, light amplitudes, and colors at minimum light. We combine our results with literature data to estimate the mean dereddened RR Lyrae color at minimum light to be mag, (V Ϫ I) p 0.58 ‫ע‬ 0.02 0, min with a star-to-star scatter of 0.024 mag. Any dependence of color on metallicity is too weak to be formally detected with the available data. One of our stars exhibits the Blazhko effect. The star's minimum light color is unchanged at the two observed phases of the star's Blazhko cycle, while the maximum light color changed significantly. This insensitivity further supports the reliability of minimum light colors as a tool for (V Ϫ I) measuring interstellar reddening.

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We present the results of an all-sky, deep optical survey for faint Local Group dwarf galaxies. Candidate objects were selected from the second Palomar Observatory Sky Survey and ESO/Science Research Council survey plates, and follow-up observations were performed to determine whether they were indeed overlooked members of the Local Group. Only two galaxies (Antlia and Cetus) were discovered this way out of 206 candidates. Based on internal and external comparisons, we estimate that our visual survey is more than 77% complete for objects larger than 1 0 in size and with a surface brightness greater than an extremely faint limit over the 72% of the sky not obstructed by the Milky Way. Our limit of sensitivity cannot be calculated exactly, but it is certainly fainter than 25 mag arcsec À2 in R, probably 25.5 and possibly approaching 26. We conclude that there are at most one or two Local Group dwarf galaxies fitting our observational criteria still undiscovered in the clear part of the sky, and roughly a dozen hidden behind the Milky Way. Our work places the ''missing satellite problem'' on a firm quantitative observational basis. We present detailed data on all our candidates, including surface brightness measurements.

We present observations of 82 Local Group dwarf galaxy candidates, of which 62 were chosen visually from ESO-SRC survey plates of the southern sky (32 of which were not previously catalogued) and the rest suggested by various sources in the literature. Two are the Local Group galaxies Antlia and Cetus; nine are more distant galaxies, though still within a few megaparsecs; 45 are background galaxies; seven are planetary (or other emission) nebulae; 15 are reflection or other Galactic nebulae; two are galaxy clusters; one is a Galactic star cluster and one is a misidentified star. We conclude that there is no large population of faint Local Group dwarf galaxies of any familiar type awaiting discovery. We point out the danger of relying on a single type of data to reach conclusions about an object.

We report the discovery of new member of the Local Group in the constellation of Antlia. Optically the system appears to be a typical dwarf spheroidal galaxy of type dE3.5 with no apparent young blue stars or unusual features. A color-magnitude diagram in I, V − I shows the tip of the red giant branch, giving a distance modulus of 25.3 ± 0.2 (1.15 Mpc ± 0.1) and a metallicity of -1.6 ± 0.3. Although Antlia is in a relatively isolated part of the Local Group it is only 1.2 degrees away on the sky from the Local Group dwarf NGC3109, and may be an associated system.