Detection of (C-13)-ethane in Jupiter's atmosphere

High-resolution (C-12)- and (C-13)-ethane spectra of Jupiter were acquired with the Kitt Peak 4 m Fourier spectrometer and the Goddard postdisperser in June 1987. A relative abundance ratio (C-12/C-13) of 94 +/- 12 was derived from the measurements. This nearly terrestrial value indicates little or no fractionation of carbon isotopes when ethane is produced in the photolysis of methane in Jupiter's atmosphere.