Radio observations of the infrared source AFCRL 809-2992

The nature of the compact H II region associated with the infrared source AFCRL 809-2992 is explored by observations at 2695 and 8085 MHz. As the radio source is partially resolved at a baseline of 2.7 km, the angular diameter may be determined 0 = 2'.'4 + 0.4 and from this the electron density is found to be 2.5 X 10. The Lyman continuum luminosity necessary to excite the nebula may be provided either by a B0.5 main-sequence star or a pr or post-main-sequence star of somewhat later spectral type. Further observations that may allow one to distinguish between these possibilities are suggested. Subject headings: infrared sources - nebulae - radio radiation