Astron. Astrophys. 315, L397-L400 (1996) First results of ISO-SWS observations of Jupiter* Th. Encrenaz1, Th. de Graauw2,3, S. Schaeidt4,5, E. Lellouch1, H. Feuchtgruber4,5, D.A. Beintema2,5, B. Bézard1, P. Drossart1, M. Griffin6, A. Heras5, M. Kessler5, K. Leech5, P. Morris5,7, P.R. Roelfsema2,5, M. Roos-Serote1, A. Salama5, B. Vandenbussche5,8, E.A. Valentijn2,5, G.R. Davis9, and D.A. Naylor10 1 DESPA, Observatoire de Paris, F-92195 Meudon, France 2 SRON, PO box 800, 9700 AV Groningen, The Netherlands 3 Kapteyn Astronomical Institute, PO box 800, 9700 AV Groningen, The Netherlands 4 Max-Planck Institut für Extraterrestrische Physik, Giessenbach Str.1, D-85748 Garching, Germany 5 ISO Science Operation Center, Astrophysics Division, ESA, PO box 50727, E-28080 Villafranca, Madrid, Spain 6 Queen Mary and Westfield College, Mile Ends Road, London E1 4NS, UK 7 SRON, Sorbonnelaan 2, 3584 CA Utrecht, The Netherlands 8 Instituut voor Sterrenkunde, University of Leuven, Celestÿnenlaan 200, B-3001 Heverlee, Belgium 9 Institute of Space and Atmospheric Studies, University of Saskatchewan, 116 Science Place, Saaskatoon, Sask. S7N 5E2, Canada 10 Dept. of Physics, University of Lethbridge, 4401 University Drive, Lethbridge, Alta. T1K 3M4, Canada Received 15 July 1996 / Accepted 20 August 1996 Abstract. The spectrum of Jupiter has been recorded between 2.75 and 14.5 m with the grating mode of the Short-Wavelength Spectrometer (SWS) of ISO. The resolving power is 1500. The main preliminary results of this observation are (1) at 3 m, the first spectroscopic signature, probably associated with NH3 ice, of the Jovian cloud at 0.5 bar and (2) the first detection of a thermal emission at the center of the CH4- band at 3.3 m, showing evidence for a high temperature in the upper jovian stratosphere (T=800 K at P=0.16 microbar). In addition, the R(2) HD line has been detected for the first time in Jupiter, using the Fabry-Pérot (FP) mode of the SWS, with a resolving power of 31000. A preliminary analysis of the HD line indicates a D/H ratio of about 2.2 10-5 . Key words: planets - Jupiter - infrared: solar system * ISO is an ESA project with instruments funded by ESA Member States (especially the PI countries: France, Germany, the Netherlands and the United Kingdom) and with the participation of ISAS and NASA Article in PDF format Article in (gzipped) PS format Last change: December 16, 1996 helpdesk.link@springer.de © European Southern Observatory (ESO) 1996