Distribution of HCN in Titan’s upper atmosphere from Cassini/VIMS observations at 3μm

Adriani, A.; Dinelli, B. M.; López‐Puertas, M.; García‐Comas, M.; Moriconi, M. L.; D’Aversa, E.; Funke, B.; Coradini, A.

doi:10.1016/j.icarus.2011.04.016

Cited by 38 publications

(53 citation statements)

References 45 publications

(41 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The HCN mixing ratio at 1000 km is about 4 Â 10 À3 . Recently, Adriani et al (2011) used the limb observations of the Visual and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft to retrieve vertical profiles of HCN from its 3 lm non-LTE emission in the region from 600 to 1100 km altitude during the daytime. The mixing ratio of HCN is about (5:5 AE 1:5Þ Â 10 À3 at 1050 km.…”

Section: Main Nitrogen Species Profilesmentioning

confidence: 99%

The neutral photochemistry of nitriles, amines and imines in the atmosphere of Titan

Loison

Hébrard

Dobrijévic

et al. 2015

Icarus

143

287

View full text Add to dashboard Cite

Section: Main Nitrogen Species Profilesmentioning

confidence: 99%

The neutral photochemistry of nitriles, amines and imines in the atmosphere of Titan

Loison

Hébrard

Dobrijévic

et al. 2015

Icarus

143

287

View full text Add to dashboard Cite

“…The vertical profiles of molecular abundances have also been investigated in the stratosphere by CIRS, and the mixing ratios of most species increase with altitude, which is a characteristic of molecules produced by photochemistry at higher altitudes that then condense in the lower stratosphere or at the tropopause (near 40 km where the temperature reaches a minimum of 70 K [ Fulchignoni et al , ]) [ Vinatier et al , , ]. This trend generally continues into the mesosphere and thermosphere as confirmed by VIMS, UVIS, and INMS measurements [see, e.g., Adriani et al , ; Koskinen et al , ; Vuitton et al , ; Cui et al , ; Magee et al , ]. Representative measurements from some of these instruments are shown in Figure .…”

Section: Titan's Atmospheric Structure and Compositionmentioning

confidence: 99%

Titan's atmosphere and climate

2017

View full text Add to dashboard Cite

Titan is the only moon with a substantial atmosphere, the only other thick N2 atmosphere besides Earth's, the site of extraordinarily complex atmospheric chemistry that far surpasses any other solar system atmosphere, and the only other solar system body with stable liquid currently on its surface. The connection between Titan's surface and atmosphere is also unique in our solar system; atmospheric chemistry produces materials that are deposited on the surface and subsequently altered by surface‐atmosphere interactions such as aeolian and fluvial processes resulting in the formation of extensive dune fields and expansive lakes and seas. Titan's atmosphere is favorable for organic haze formation, which combined with the presence of some oxygen‐bearing molecules indicates that Titan's atmosphere may produce molecules of prebiotic interest. The combination of organics and liquid, in the form of water in a subsurface ocean and methane/ethane in the surface lakes and seas, means that Titan may be the ideal place in the solar system to test ideas about habitability, prebiotic chemistry, and the ubiquity and diversity of life in the universe. The Cassini‐Huygens mission to the Saturn system has provided a wealth of new information allowing for study of Titan as a complex system. Here I review our current understanding of Titan's atmosphere and climate forged from the powerful combination of Earth‐based observations, remote sensing and in situ spacecraft measurements, laboratory experiments, and models. I conclude with some of our remaining unanswered questions as the incredible era of exploration with Cassini‐Huygens comes to an end.

show abstract

“…The HCN mixing ratio at 1000 km is about 4 × 10 −3 . Recently, Adriani et al (2011) used the limb observations of the Visual and Infrared Mapping Spectrometer (VIMS) onboard the Cassini spacecraft to retrieve vertical profiles of HCN from its 3 μm non-LTE emission in the region from 600 to 1100 km altitude at daytime. The mixing ratio of HCN is about (5.5 ± 1.5) × 10 −3 at 1050 km.…”

Section: Hcn Observationsmentioning

confidence: 99%

Neutral production of hydrogen isocyanide (HNC) and hydrogen cyanide (HCN) in Titan’s upper atmosphere

Hébrard

Dobrijévic

Loison

et al. 2012

A&A

116

View full text Add to dashboard Cite

Aims. Following the first detection of hydrogen isocyanide (HNC) in Titan's atmosphere, we have devised a new neutral chemical scheme for hydrogen cyanide (HCN) and HNC in the upper atmosphere of Titan. Methods. Our updated chemical scheme contains 137 compounds (with C, H, O and N elements) and 788 reactions (including 91 photolysis processes). To improve the chemistry of HNC and HCN, a careful review of the literature has been performed to retrieve critical reaction rates and to evaluate their uncertainty factors. We have also estimated the reaction rates of 48 new reactions using simple capture theory. Results. Our photochemical model gives abundances of HNC and HCN in reasonable agreement with observations. An uncertainty propagation study shows large uncertainties for HNC and relatively moderate uncertainties for HCN. A global sensitivity analysis pinpoints some key reactions to study as a priority to improve the predictivity of the model. Conclusions. In particular, our knowledge of the isomerization of HNC via the reaction H + HNC → HCN + H and the chemistry of H 2 CN needs to be improved. This study of the neutral chemistry taking place in the upper atmosphere of Titan is a prerequisite for future ionospheric models since ion-neutral reactions may also contribute significantly to HNC and HCN production.

show abstract

Distribution of HCN in Titan’s upper atmosphere from Cassini/VIMS observations at 3μm

Cited by 38 publications

References 45 publications

The neutral photochemistry of nitriles, amines and imines in the atmosphere of Titan

The neutral photochemistry of nitriles, amines and imines in the atmosphere of Titan

Titan's atmosphere and climate

Neutral production of hydrogen isocyanide (HNC) and hydrogen cyanide (HCN) in Titan’s upper atmosphere

Contact Info

Product

Resources

About