Search Publications
Invited review: Infrared spectroscopy of planetary atmospheres: Searching for insights into their past and present histories
Encrenaz, Thérèse
This article reflects my personal experience and illustrates some developments in the field of planetary spectroscopy, achieved within the Planetology Group of Paris Observatory over the past fifty years. Over these decades, planetary spectroscopy has led to the identification of minor atmospheric species with mixing ratios as low as a few parts p…
Temporal variation of the 3-micron hydrocarbon emissions at the 8-micron north polar hot spot of Jupiter: Comparison with solar wind activity
Kim, Sang Joon; Yung, Yuk L.; Miller, Steve +5 more
We have obtained Gemini/GNIRS 3.3-3.4 µm spectra of Jupiter at 65o North latitude over a range of longitudes roughly centered on the 8-µm CH4 north polar hot spot (8CNPHS). The spectra were measured on four occasions during a four-month period in 2018, in order to search for variability of the 3-µm emissions…
Probable detection of hydrogen sulphide (H2S) in Neptune's atmosphere
Fletcher, Leigh N.; Bézard, Bruno; Irwin, Patrick G. J. +4 more
Recent analysis of Gemini-North/NIFS H-band (1.45-1.8 µm) observations of Uranus, recorded in 2010, with recently updated line data has revealed the spectral signature of hydrogen sulphide (H2S) in Uranus's atmosphere (Irwin et al., 2018). Here, we extend this analysis to Gemini-North/NIFS observations of Neptune recorded in 2009 …
Photochemistry, mixing and transport in Jupiter's stratosphere constrained by Cassini
Sinclair, J. A.; Hue, V.; Cavalié, T. +2 more
In this work, we aim at constraining the diffusive and advective transport processes in Jupiter's stratosphere, using Cassini/CIRS observations published by Nixon et al. (2007,2010). The Cassini-Huygens flyby of Jupiter on December 2000 provided the highest spatially resolved IR observations of Jupiter so far, with the CIRS instrument. The IR spec…
Models of bright storm clouds and related dark ovals in Saturn's Storm Alley as constrained by 2008 Cassini/VIMS spectra
Baines, K. H.; Sromovsky, L. A.; Fry, P. M.
A 5° latitude band on Saturn centered near planetocentric latitude 36°S is known as "Storm Alley" because it has been for several extended periods a site of frequent lightning activity and associated thunderstorms, first identified by Porco et al. (2005). The thunderstorms appeared as bright clouds at short and long continuum wavelengths, and over…
Temperatures and CH4 mixing ratios near the homopause of the 8 µm north polar hot spot of Jupiter
Orton, G. S.; Kim, Sang Joon; Yung, Yuk L. +4 more
We have derived homopause temperatures of 180-250 K for the 8-µm north-polar hot spot (8NPHS) of Jupiter by fitting CH4 emission models to 3 and 8 µm spectra of the 8NPHS obtained 24 days apart in 2013. From the fits, we find that CH4 mixing ratios at the 8NPHS are consistent with those reported by Kim et al. (201…
Cloud clearing in the wake of Saturn's Great Storm of 2010-2011 and suggested new constraints on Saturn's He/H2 ratio
Baines, K. H.; Sromovsky, L. A.; Momary, T. W. +1 more
Saturn's Great Storm of 2010-2011 produced a planet-encircling wake that slowly transitioned from a region that was mainly dark at 5 µm in February 2011 to a region that was almost entirely bright and remarkably uniform by December of 2012. The uniformity and high emission levels suggested that the entire wake region had been cleared not onl…
The 6-7 µm spectrum of Titan from ISO/SWS observations
Lellouch, Emmanuel; Feuchtgruber, Helmut; Courtin, Régis +1 more
We have analyzed spectroscopic observations of Titan performed in January 1997 by the Short Wavelength Spectrometer (SWS) on the Infrared Space Observatory in the wavelength range from 5.3 to 7.0 µm (1422-1890 cm-1). This spectral interval is of particular interest because it contains various molecular transitions, particularly th…
Mid-infrared spectroscopy of Uranus from the Spitzer infrared spectrometer: 2. Determination of the mean composition of the upper troposphere and stratosphere
Fletcher, Leigh N.; Moses, Julianne I.; Line, Michael R. +7 more
Mid-infrared spectral observations Uranus acquired with the Infrared Spectrometer (IRS) on the Spitzer Space Telescope are used to determine the abundances of C2H2, C2H6, CH3C2H, C4H2, CO2, and tentatively CH3 on Uranus at the time of the …
Neptune at summer solstice: Zonal mean temperatures from ground-based observations, 2003-2007
de Pater, Imke; Fletcher, Leigh N.; Irwin, Patrick G. J. +3 more
Imaging and spectroscopy of Neptune's thermal infrared emission from Keck/LWS (2003), Gemini-N/MICHELLE (2005); VLT/VISIR (2006) and Gemini-S/TReCS (2007) is used to assess seasonal changes in Neptune's zonal mean temperatures between Voyager-2 observations (1989, heliocentric longitude Ls = 236 °) and southern summer solstice (2005, L<…