Broadband submillimeter spectroscopy of HCN, NH3, and PH3 in the troposphere of Jupiter

We report measurements of the Jupiter brightness spectrum in the 850-μm and 1100-μm atmospheric windows with a spectral resolution of 125 MHz, obtained with a Fourier transform spectrometer on the James Clerk Maxwell Telescope. Three results were obtained. First, the predicted absorption features due to the rotational lines of HCN at 266 and 354 GHz were not detected within our error limits of less than 1%. We establish new upper limits for the HCN abundance in the jovian troposphere for five assumed abundance distributions and for two assumed NH3abundances. The upper limits are 1.7 to 13 times smaller than the abundance value obtained in the only reported detection of HCN in Jupiter prior to the impact of Shoemaker–Levy 9. Second, the continuum brightness temperature spectrum at 850 μm was determined and is in agreement with previous measurements, but has large error bars due to uncertainties in the photometric calibration. We estimate the ammonia abundance in the 1–2 bar region to be 1.7 times solar, but this result is tentative since scattering by NH3cloud particles and absorption by gaseous H2S were neglected in our atmospheric model. Finally, the first rotational line of PH3at 267 GHz was not detected, a result which we demonstrate is consistent with the statistical noise level in these measurements, with current values of the spectroscopic parameters, and with phosphine measurements at other wavelengths.

[1]  J. Ferris,et al.  The photolysis of NH3 in the presence of substituted acetylenes: a possible source of oligomers and HCN on Jupiter. , 1992, Icarus.

[2]  E. I. Robson,et al.  Submillimeter and millimeter observations of jupiter , 1986 .

[3]  P. Ade,et al.  100 mK bolometers for the submillimetre common-user bolometer array (scuba) I. Design and construction , 1996 .

[4]  J. Ruze.  Antenna tolerance theory—A review , 1966 .

[5]  T. Owen,et al.  Non-Detection of Hydrogen Cyanide on Jupiter , 1995 .

[6]  R. Prinn,et al.  The Predicted Abundances of Deuterium-bearing Gases in the Atmospheres of Jupiter and Saturn , 1988 .

[7]  Eugene Serabyn,et al.  Detection of the 267 GHz J = 1-0 Rotational Transition of PH3 in Saturn with a New Fourier Transform Spectrometer , 1994 .

[8]  B. Fegley,et al.  Chemical Models of the Deep Atmospheres of Jupiter and Saturn , 1994 .

[9]  S. Ridgway,et al.  High-resolution spectra of Jupiter in the 744-980 inverse centimeter spectral range , 1979 .

[10]  JOHN S. Lewis,et al.  Hot-atom synthesis of organic compounds on Jupiter , 1979 .

[11]  D. Naylor,et al.  Atmospheric transmission at submillimetre wavelengths from Mauna Kea , 1991 .

[12]  E. Serabyn,et al.  The detection of HCN on Jupiter , 1981 .

[13]  E. R. Cohen,et al.  Analysis of the far infrared H2-He spectrum , 1982 .

[14]  J. Joiner,et al.  Search for sulfur (H/sub 2/S) on Jupiter at millimeter wavelengths , 1992 .

[15]  D. Naylor,et al.  Extension of the solar limb at sub-millimeter and millimeter wavelengths , 1992 .

[16]  G. R. Davis.  The far infrared continuum absorption of water vapour , 1993 .

[17]  D. Gautier,et al.  Ammonia vertical density profiles in Jupiter and Saturn from their radioelectric and infrared emissivities , 1980 .

[18]  JOHN S. Lewis,et al.  Chemical structure of the deep atmosphere of Jupiter , 1978 .

[19]  C. Sagan.  The Production of Organic Molecules in Planetary Atmospheres. , 1960 .

[20]  S. Gulkis,et al.  Earth-based radio observations of Jupiter - Millimeter to meter wavelengths , 1976 .

[21]  A. Bar-Nun,et al.  Moist convection and the abundances of lightning-produced CO, C2H2, and HCN on Jupiter , 1988 .

[22]  J. Jenkins,et al.  Laboratory measurements of the microwave opacity of gaseous Ammonia (NH3) under simulated conditions for the Jovian atmosphere , 1986 .

[23]  V. M. Devi,et al.  THE HITRAN MOLECULAR DATABASE: EDITIONS OF 1991 AND 1992 , 1992 .

[24]  E. I. Robson,et al.  A millimetre/submillimetre common user photometer for the James Clerk Maxwell Telescope , 1990 .

[25]  J. Ferris,et al.  Photosynthesis of organic compounds in the atmosphere of Jupiter , 1975, Nature.

[26]  D. Naylor,et al.  Eliminating channel spectra in Fourier transform spectroscopy. , 1988, Applied optics.

[27]  T. Encrenaz,et al.  An estimate of the PH3, CH3D, and GeH4 Abundances on Jupiter from the Voyager IRIS data at 4.5 μm , 1982 .

[28]  A Goldman,et al.  The HITRAN database: 1986 edition. , 1987, Applied optics.

[29]  Noelle A. Scott,et al.  Management and study of spectroscopic information: The GEISA program , 1992 .

[30]  L. Wallace.  The structure of the Uranus atmosphere , 1980 .

[31]  H. Müller,et al.  Submillimeter, millimeter, and microwave spectral line catalog. , 1985, Applied optics.

[32]  P. Varanasi.  Shapes and widths of ammonia lines collision-broadened by hydrogen. , 1972 .

[33]  P. Mauas,et al.  Infrared and Submillimeter Diagnostics of Activity and Flares , 1994 .

[34]  A. Chédin,et al.  The tropospheric gas composition of Jupiter's north equatorial belt /NH3, PH3, CH3D, GeH4, H2O/ and the Jovian D/H isotopic ratio , 1982 .

[35]  T. A. Clark,et al.  Polarizing Fourier transform spectrometer for astronomical spectroscopy at submillimeter and mid-infrared wavelengths , 1994, Astronomical Telescopes and Instrumentation.

[36]  Matthew Joseph Griffin,et al.  The near-millimeter brightness temperature spectra of Uranus and Neptune , 1993 .

[37]  A. Ben-Reuven.  Impact Broadening of Microwave Spectra , 1966 .

[38]  Donald E. Jennings,et al.  Exploration of the Solar System by Infrared Remote Sensing: Retrieval of physical parameters from measurements , 1992 .

[39]  D. Strobel,et al.  HCN formation on Jupiter: The coupled photochemistry of ammonia and acetylene , 1983 .

[40]  M. J. Griffin,et al.  The influence of background power on the performance of an ideal bolometer , 1986 .

[41]  R. E. Dickerson,et al.  Chemical evolution and the origin of life. , 1978, Scientific American.

[42]  P. Jacquinot.  New developments in interference spectroscopy , 1960 .

[43]  H. Matthews,et al.  The James Clerk Maxwell Telescope : a guide for the prospective user , 1991 .

[44]  P. Dore,et al.  Far infrared absorption in normal H2 from 77 to 298 K , 1983 .

[45]  J. Joiner,et al.  Modeling of Jupiter's millimeter wave emission utilizing laboratory measurements of ammonia (NH3) opacity , 1991 .

[46]  A. Bar-Nun,et al.  The contribution by thunderstorms to the abundances of CO, C2H2, and HCN on Jupiter , 1985 .

[47]  Steven T. Massie,et al.  Models of the millimeter-centimeter spectra of the giant planets , 1985 .

[48]  H. Pickett,et al.  Pressure broadening of phosphine by hydrogen and helium , 1981 .

[49]  J. Ferris,et al.  Formation of hydrogen cyanide and acetylene oligomers by photolysis of ammonia in the presence of acetylene: applications to the atmospheric chemistry of Jupiter , 1988 .

[50]  F. Rohart,et al.  Foreign gas relaxation of the J=0→1 transition of HC15N. A study of the temperature dependence by coherent transients , 1987 .

[51]  JOHN S. Lewis,et al.  Vertical distribution of disequilibrium species in Jupiter's troposphere , 1984 .

[52]  B. Bézard,et al.  Detectability of HD and non-equilibrium species in the upper atmospheres of the giant planets from their submillimeter spectrum , 1986 .

[53]  Stanley L. Miller,et al.  Molecular Synthesis in Simulated Reducing Planetary Atmospheres. , 1960 .

[54]  J. Ferris,et al.  HCN and chemical evolution: the possible role of cyano compounds in prebiotic synthesis. , 1984, Tetrahedron.

[55]  S. L. Miller,et al.  Electric discharge synthesis of HCN in simulated Jovian atmospheres. , 1987, Icarus.

[56]  A. Lacis,et al.  Tropospheric gas composition and cloud structure of the Jovian North Equatorial Belt , 1993 .

[57]  F. X. Kneizys,et al.  Line shape and the water vapor continuum , 1989 .

[58]  E. Weisstein,et al.  SUBMILLIMETER LINE SEARCH IN JUPITER AND SATURN , 1996 .

[59]  A. Chédin,et al.  The helium abundance of Jupiter from Voyager , 1980 .