Infrared line emission from the Orion Nebula: Detection of (S III) (18. 71. mu. ) and (O III) (88. 35. mu. )

Line emission from the Orion Nebula has been detected at 18.71 and 88.35 ..mu.. with a high resolving power (approx.10/sup 4/), rapid-scan Michelson interferometer on the 91 cm telescope of NASA's Gerard P. Kuiper Airborne Observatory. Identification of these lines with expected transitions of (S III) and (O III) is discussed and the measured frequencies and fluxes compared with theoretical predictions. The 18.71 ..mu.. line was resolved and has a half power velocity width of about 28 km s/sup -1/. (AIP)