OH Emission Bands in the Spectrum of the Night Sky.

High-resolution spectra of the infrared night sky obtained at Yerkes Observatory have shown conclusively that the previously unidentified infrared emissions are due to the rotation-vibration spectrum of OH. The agreement between the vibrational spacing, the rotational constants, and the doublet structure of the emissions and the predicted OH structure is excellent. The observation of vibrational levels up to v = 9 shows that small inaccuracies exist in the currently accepted vibrational constants. A more accurate determination of these constants could be made, despite the low dispersion of the spectrograph. Other bands of this system of OH occur in the region of 1 j# and may account for the radiation detected by Stebbins, Whitford, and Swings, which has been attributed to N2.