Photometry of the nearby irregular galaxy, NGC 6822

NGC 6822 is a dwarf irregular in the Local Group at α=19^h 42^m, δ= —14° 53'.1 (1950). The color-magnitude diagram is plotted from measures on photographic plates calibrated by a photoelectric sequence. Photometry is complete to V=19^h.5 (M_ν=—5). Major features are bright blue supergiants, the brightest star having M_ν=—9, and a sequence of very red supergiants only one-half magnitude fainter than the blue, many of which have light variations lasting over 1000 days. A significant number of stars lie in the Hertzsprung gap. Two-color photometry shows there is intervening reddening of 0^m.27. A luminosity function is calculated. Thirty-two variable stars are discussed, of which 13 are Cepheids, two are red semiregulars, one may be eclipsing, and the others are irregular. The 11 variables with 1^m.6< (B-V)_0