Calibration stars

This note describes lists of infrared and optically-bright stars that might be observed for calibration purposes by orbiting sensors, particularly those with sensitivity to both infrared and visible radiation. The lists are a subset of the Catalog of Infrared Observations. The stars chosen generally meet the following criteria: they possess a visual magnitude less than +6, and an infrared brightness (in the 1-5 micrometer range) greater than that of the standard star Vega. The stars are strictly southern objects (i.e., their declinations are negative), and most are cool stars of spectral classes K and M. We present three tables: the first lists optically and infrared-bright single stars, useful for focus or point-spread function studies; the second gives pairs of stars useful for determining the absolute orientation of the field of view, and the third lists stars useful for performing an absolute flux calibration. While these are not the only stars that might serve for these purposes, they are well distributed across the southern sky and some should be visible at all times.