Showing papers by "Mark C. Price published in 1996"
TL;DR: The Long-Wavelength Spectrometer (LWS) is one of two complementary spectrometers aboard the European Space Agency's Infrared Space Observatory (ISO) (Kessler et al., 1996) as mentioned in this paper.
Abstract: The Long-Wavelength Spectrometer (LWS) is one of two complementary spectrometers aboard the European Space Agency's Infrared Space Observatory (ISO) (Kessler et al., 1996AA a companion paper (Swinyard et al, 1996) describes its performance and calibration.
42 citations
Journal Article•
TL;DR: The R(1) rotational line of HD at 5623 mu m has been detected for the first time on Saturn using the Long Wavelength Spectrometer (LWS) on board the Infrared Space Observatory (ISO) as mentioned in this paper.
Abstract: The R(1) rotational line of HD at 5623 mu m has been detected for the first time on Saturn using the Long Wavelength Spectrometer (LWS) on board the Infrared Space Observatory (ISO) The measurements were made using the LWS in Fabry-Perot mode in January 1996 during the ISO performance verification phase The measured spectrum has been compared with atmospheric models to determine the HD/H-2 abundance ratio The best model fit to the measured spectrum was obtained with a D/H ratio in hydrogen of 23x10(-5); D/H values between 15x10(-5) and 35x10(-5) are however also compatible with the data This result is intermediate between the saturnian value derived from ground-based observations of methane and its deuterated isotope, and the preliminary determination of the jovian D/H ratio measured by the mass spectrometer in the Galileo probe The initial Saturn measurements reported here will be repeated to improve the signal-to-noise ratio, and LWS observations of HD on Jupiter, Uranus and Neptune will also be made
18 citations
Journal Article•
TL;DR: The spectrum of Saturn from 43 to 197μm was measured with the ISO Long Wavelength Spectrometer (LWS) during the performance verification phase of the mission as discussed by the authors, and the spectrum was compared with an atmospheric radiative-transfer model and four results were obtained: first, the slope of the measured continuum within each detector passband is in good agreement with the model; second, absorption features due to ammonia and phosphine were unambiguously detected, and all detected features were attributed to these two molecules; third, the ammonia absorption features agree reasonably well with the nominal model
Abstract: The spectrum of Saturn from 43 to 197μm was measured with the ISO Long Wavelength Spectrometer (LWS) during the performance verification phase of the mission. The measurements were made using the LWS in grating mode, with spectral resolutions of 0.29μm from 43 to 90μm and 0.6μm from 90 to 197μm. The spectrum was compared with an atmospheric radiative-transfer model and four results were obtained: first, the slope of the measured continuum within each detector passband is in good agreement with the model; second, absorption features due to ammonia and phosphine were unambiguously detected, and all detected features were attributed to these two molecules; third, the ammonia absorption features agree reasonably well with the nominal model (based on Voyager IRIS measurements); and fourth, the phosphine absorption features disagree with the nominal model. Superior agreement with the measured spectrum was obtained with a modified PH_3_ profile in which the tropospheric mixing ratio was increased to 7x10^-6^ and the cutoff due to photodissociation was lowered to 300mbar. These results are based on trial observations during performance verification of the LWS, and provide an indication of the results we expect to obtain when the spectrum of Saturn is measured comprehensively later in the mission.
18 citations