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RECENT ADVANCES IN THE SPECTROSCOPY OF PLANETARY AND EXOPLANETARY ATMOSPHERES : WHAT IS OUT THERE ?. Hitran 2010 Pierre Drossart LESIA, Observatoire de Paris. Spectra of Giant Planets. Day side (Reflected sunlight). Thermal emission. XO-1b Tinetti et al, 2010. G. Kuiper, ApJ, 1947.
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RECENT ADVANCES IN THE SPECTROSCOPY OF PLANETARY AND EXOPLANETARY ATMOSPHERES : WHAT IS OUT THERE ? Hitran 2010 Pierre Drossart LESIA, Observatoire de Paris
Spectra of Giant Planets Day side (Reflected sunlight) Thermal emission Hitran 2010 - Cambridge
XO-1b Tinetti et al, 2010 G. Kuiper, ApJ, 1947 Hitran 2010 - Cambridge
Line formation in Jupiter’s atmosphere (CH44 band) Growth of line through vertical atmospheric integration Hitran 2010 - Cambridge
Spectra of Jupiter: Line formation in the thermal spectrumSimulations at high/low resolution Radiative transfer in Planetary atmospheres
NICMOS: transmission spectroscopy XO-1b, terminator Hitran 2010 - Cambridge Tinetti, et al., ApJ, 2010
Thermal structure retrieval o Machalek et al., 2009 + Knutson et al., 2007 1500 K 1000 K Hitran 2010 - Cambridge Tinetti, et al., ApJ, 2010
Non-LTE emissions of CH4 in giant planets ISO observation of CH4 non-LTE emission on Jupiter Drossart et al, ESA-SP 427, 1999 Hitran 2010 - Cambridge
CH4 non LTE emission in exoplanets ? Swain et al, Nature, 2010 HD189733b Hitran 2010 - Cambridge
Cassini Saturn spectroscopic observations in the infrared CIRS has two combined interferometers, operating in the far-infrared (10-600 cm-1) and mid-infrared (600-1400 cm-1). VIMS is an imaging visible and near infrared spectrometer (0.3-5 micron) Hitran 2010 - Cambridge
Saturn 80°S at 100 and 300 km C2H2 Flasar et al., Sci. 2005 C4H2 et CH3C2H C2H6 Radiance (W cm-2 sr-1 / cm-1) C3H8 CO2 Hitran 2010 - Cambridge
Saturn at 80°S 100 and 300 km CH4 CH3D Flasar et al., Sci. 2005 Radiance (W cm-2 sr-1 / cm-1) Hitran 2010 - Cambridge
First results from Herschel in the solar system First publications in Astronomy & Astrophysics – May 2010
Instruments et observations __ • Observatory mode access from proposals • “Key Programs” (– x 100 h, “legacy”), priority • normal programs (AO 20 may 2010) ___ __ ___ _____ __ Hitran 2010 - Cambridge
Neptune spectrum from PACS Lellouch et al., A&A 2010 Hitran 2010 - Cambridge
Methane in the stratosphere of Neptune Lellouch et al. A & A 2010 Orton, Encrenaz et al. 2007
Venus atmosphere • Venus Express observations A new start in Venus atmosphere observations after a long gap since Venera 15 and Vega russian missions Next mission Akatsuki (Jaxa) Launched on May 20 Hitran 2010 - Cambridge
Venus NIR day side spectrum Venus Express/VIRTIS spectra in the NIR (day side) Most of the absorptions : CO2 ! Hitran 2010 - Cambridge
Depression in the polar region Grey are VMC images N. Ignatiev Hitran 2010 - Cambridge Ignatiev et al., JGRE 2009
Telluric planets : Venus thermal emission in the dark side • Thermal emission originating from the 0-45 km altitude range in spectral windows • Accurate knowledge of CO2 opacity is crucial • Weak allowed bands • Pressure-induced bands • Far wing line shape • Deep atmosphere of Venus Challenge for spectroscopy : CO2 up to 90 bars, 450 K at the surface Database : HITEMP, CDSD-750 VIRTIS-Mspectrum H2O CO2 H2O H2O CO2 CO2 CO2 H2O 1.0 m 1.27 m 1.18 m 1.74 m 2.3 m 1.10 m Hitran 2010 - Cambridge
Venus nightside windows2.3 m • CFHT/FTS observations (Res = 0.15 cm-1) [Taylor et al. 1997] • Altitude range: 26-45 km • Absorbers: CO2, H2O, HDO, CO, OCS, SO2, HF CO2 Hitran 2010 - Cambridge
Deep atmosphere of Venus by VIRTIS/Venus Express CO2 CO H2O HDO OCS SO2 Marq et al., JGRE, 2008 Hitran 2010 - Cambridge
Venus day side observations at 4.3 micron : CO2non – LTE emissions Gilli, Lopez-Valverde et al., JGRE 2009 Hitran 2010 - Cambridge
Gravity waves observed in CO2 non-LTE emission of Venus Day side up/night side down Center on South pole Polar vortex in red Garcia et al., JGRE, 2009 Hitran 2010 - Cambridge
O2 intensity : night side emission of Venus at 1.27 micron Mean vertical brightness = 0.5 MR 1.27 micron emission of Venus Gérard et al., Icarus, 2009 01/01/2020 Hitran 2010 - Cambridge 25/20
Piccioni et al., PNAS, 2008 Hitran 2010 - Cambridge
Mars exploration in the XXIth century The War of the Worlds : the Revenge Mars Reconnaissance Orbiter (2006) Coming soon… Mars Science Laboratory (2011) Mars Trace Gas Orbiter (2016) Mars Odyssey (2002) Mars Express (2003) Mars Exploration rovers (2003) Hitran 2010 - Cambridge
The infrared spectrum of Martian atmosphere Solar reflected Thermal CO2 H2O CO CO2 Hydrated silicates CO2 CO2 Reflected sunlight -> mineralogy Thermal emission -> T(z), winds ISO-SWS Lellouch et al., 2000
The 1237-1243 cm-1 spectrum of Mars(TEXES, IRTF)All lines identified down to depths of 0.3%S/N > 1000 in the continuum H2O2, 10-7 synthetic TEXES data
First IR detection of H2O2 on Mars H2O2 and CO2 lines at 1241.6 cm-1 H2O2 H2O2 CO2 Encrenaz et al. Icarus 2004
Mars Trace Gas OrbiterNASA / ESA 2016 • Science objectives • Detection of trace molecules CH4, C2H2, C2H6, NO2, N2O, H2S, SO2, H2O, O3, isotopologues • Determine the type of activiy : geological, or biological from the molecular ratio • Characterize spatial and temporal variations • Find the correlations between trace species to constrain the chemistry • Localize the sources • Trace the origin of gases • Determine uncertainty of a landing mission for EXOMARS Hitran 2010 - Cambridge
Some trace gases to search for with TGOnadir and limb observations • The spectral domain has been optimized for several simultaneous gas detection • Sensitivity to methane • 1ppb in 6 s 50 km2 cartography • 50 ppt in solar occultation mode for detection
Conclusions about (exo)planetary atmospheres spectroscopy What is out there ? At first order : CO2 , CH4 , H2O , CO … but we still do not fully understand the spectroscopy of these molecules! • Isotopes, • line shapes, • CIA, • line mixing, • relaxation coefficients, • etc. Trace constituents Telluric planets : H2O2, OH, H2CO Giant planets : NH3, PH3, H2S Hitran 2010 - Cambridge
Acknowledgements to • Bruno Bézard • Régis Courtin • Emmanuel Lellouch • Dominique Bockelee • Giovanna Tinetti • Athena Coustenis • Thérèse Encrenaz • Giuseppe Piccioni • Miguel Lopez-Valverde • Raphaël Garcia Hitran 2010 - Cambridge