New experimental constraints on the composition and structure of tholins

Quirico, E.; Montagnac, Gilles; Lees, Victoria; McMillan, Paul F.; Szopa, Cyril; Cernogora, Guy; Rouzaud, Jean-Noël; Simon, Patrick; Bernard, Jean-Michel; Coll, Patrice; Fray, N.; Minard, Robert D.; Raulin, F.; Reynard, Bruno; Schmitt, Bernard

doi:10.1016/j.icarus.2008.07.012

Cited by 154 publications

(219 citation statements)

References 42 publications

Supporting

Mentioning

205

Contrasting

Order By: Relevance

“…Nevertheless, the mere formation of an organic material with spectral characteristics close to that observed in UCAMMs, i.e. in which up to several tens of percent of N have been incorporated and with low amounts of oxygen, requires the presence of a carbonaceous precursor and energetic processes in a N-dominated environment Ong et al 1996;Hammer et al 2000;Rodil et al 2001;Quirico et al 2008;Gerakines et al 2004;Moore et al 2003;Hudson et al 2001). Such conditions are gathered at the surface of some objects, which are orbiting at large heliocentric distances, beyond the trans-Neptunian region, with N 2 -rich icy surfaces (Schaller & Brown 2007;Levi & Podolak 2011).…”

Section: Introductionmentioning

confidence: 99%

Irradiation of nitrogen-rich ices by swift heavy ions

Augé

Dartois

Engrand

et al. 2016

A&A

View full text Add to dashboard Cite

Context. Extraterrestrial materials, such as meteorites and interplanetary dust particles, provide constraints on the formation and evolution of organic matter in the young solar system. Micrometeorites represent the dominant source of extraterrestrial matter at the Earth's surface, some of them originating from large heliocentric distances. Recent analyses of ultracarbonaceous micrometeorites recovered from Antarctica (UCAMMs) reveal an unusually nitrogen-rich organic matter. Such nitrogen-rich carbonaceous material could be formed in a N 2 -rich environment, at very low temperature, triggered by energetic processes. Aims. Several formation scenarios have been proposed for the formation of the N-rich organic matter observed in UCAMMs. We experimentally evaluate the scenario involving high energy irradiation of icy bodies subsurface orbiting at large heliocentric distances. Methods. The effect of Galactic cosmic ray (GCR) irradiation of ices containing N 2 and CH 4 was studied in the laboratory. The N 2 -CH 4 (90:10 and 98:2) ice mixtures were irradiated at 14 K by 44 MeV Ni 11+ and 160 MeV Ar 15+ swift heavy ion beams. The evolution of the samples was monitored using in-situ Fourier transform infrared spectroscopy. The evolution of the initial ice molecules and new species formed were followed as a function of projectile fluence. After irradiation, the target was annealed to room temperature. The solid residue of the whole process left after ice sublimation was characterized in-situ by infrared spectroscopy, and the elemental composition was measured ex-situ. Results. The infrared bands that appear during irradiation allow us to identify molecules and radicals (HCN, CN − , NH 3 , ...). The infrared spectra of the solid residues measured at room temperature show similarities with that of UCAMMs. The results point towards the efficient production of a poly-HCN-like residue from the irradiation of N 2 -CH 4 rich surfaces of icy bodies. The room temperature residue provides a viable precursor for the N-rich organic matter found in UCAMMs.

show abstract

Section: Introductionmentioning

confidence: 99%

Irradiation of nitrogen-rich ices by swift heavy ions

Augé

Dartois

Engrand

et al. 2016

A&A

View full text Add to dashboard Cite

show abstract

“…2a, we present the derived τ-spectra for the haze along with the spectra of tholins available from the literature (Khare et al 1984;Quirico et al 2008;Gautier et al 2012). In the 315−502 km range, the derived τ-spectra are largely similar, and the spectra derived in that range are omitted for clarity.…”

Section: Resultsmentioning

confidence: 99%

“…1a) in which the τ-spectra are most uncertain. a) The tholin spectra are adopted from the literature (Khare et al 1984;Quirico et al 2008;Gautier et al 2012). b) Spectra measured (Clark et al 2009) for the alkane powders C 6 H 14 (hexane), C 10 H 22 (decane), and C 20+ H 42+ (paraffin) provide a satisfactory fit to the three major peaks of the haze τ-spectra at 2.3, 3.4, and 4.3 μm.…”

Section: Resultsmentioning

confidence: 99%

“…We then compare our results with a) the spectral characteristics of laboratory-made tholins reported in the literature (e.g., Khare et al 1984;Quirico et al 2008;Gautier et al 2012); b) those derived from highaltitude (600−1250 km) emission observed by Cassini/VIMS López-Puertas et al 2013); and c) the low-altitude (20−130 km) results from the Huygens/Aerosol Collector and Pyrolyser (ACP; Israël et al 2005). …”

Section: Introductionmentioning

confidence: 88%

See 1 more Smart Citation

Spectral characteristics of the Titanian haze at 1−5 micron fromCassini/VIMS solar occultation data

Kim

Courtin

2013

A&A

View full text Add to dashboard Cite

We retrieved optical-depth spectra of the Titanian haze in the range 1−5 μm from solar occultation data obtained by the Cassini/Visual Infrared Mapping Spectrometer (VIMS) at altitudes of 59−502 km. Only limited wavelength intervals within this spectral range have been analyzed before. The haze spectra we retrieved are mostly similar to those of alkane particles (or powders), with three major absorption peaks typical of alkane powders at 2.3, 3.4, and 4.3 μm. This result suggests that at least in the ∼60−500 km altitude range, the Titanian haze is mostly composed of alkane particles, possibly with some trace impurities. The absence of the 3.0 and 4.6 μm features excludes the molecules containing NH and CN bonds that are typical of laboratory-made tholins reported in the literature. The alkane-like spectral characteristics of the haze we observed at ∼60−500 km differ from previous results obtained at different or overlapping altitudes: a) the presence of aromatic compounds derived from solar-pumped emissions observed at high altitude (600−1250 km) by Cassini/VIMS near 3.3 μm; and b) the detection of HCN and NH 3 in the cores of haze particles collected at low altitude (20−130 km) by the Huygens/Aerosol Collector and Pyrolyser (ACP). We suggest that these different characteristics arise from different structural layers formed by coagulation/coalescence during particle sedimentation.

show abstract

“…PANHs have been predicted to be major components of the atmosphere and the surface of Titan (Imanaka et al 2004;McCord et al 2006;Quirico et al 2008;Kim & Kaiser 2009;Landera & Mebel 2010) within the category of material referred to as tholins, which are believed to be present across the outer solar system and responsible for the varying reddish hues of bodies such as Titan, Callisto, Pluto, and Charon with the exact composition of the tholin determining the exact color (Dalle Ore et al 2011;Cruikshank et al 2015).…”

Section: Introductionmentioning

confidence: 99%

PRESSURE EFFECTS IN POLYCYCLIC AROMATIC NITROGENATED HETEROCYCLES (PANHs): DIAGNOSTIC QUALITIES AND COSMOBAROMETRY POTENTIAL

Montgomery

Sephton

2016

ApJ

View full text Add to dashboard Cite

The influence of polycyclic aromatic nitrogen heterocycles (PANHs), which have been suggested as contributors to the interstellar IR emission bands, on interstellar emission features is difficult to constrain because their infrared characteristics are strongly similar to those for polycyclic aromatic hydrocarbons (PAHs). One possible solution is to seek a means of visualizing the presence of PANHs that provides information that is distinct from that for PAHs. Although PANHs and PAHs have similar infrared characteristics in many settings, this relationship may not be universally maintained. We have used in situ high-pressure synchrotron-source Fourier transform infrared spectroscopy to determine that the responses of two representative molecules, acridine and anthracene, differ at high pressures (>ca. 1 GPa). Because there are a number of high-pressure environments that can be remotely observed by infrared spectroscopy, they represent a potential to glimpse the distribution of PANHs across the cosmos.

show abstract

New experimental constraints on the composition and structure of tholins

Cited by 154 publications

References 42 publications

Irradiation of nitrogen-rich ices by swift heavy ions

Irradiation of nitrogen-rich ices by swift heavy ions

Spectral characteristics of the Titanian haze at 1−5 micron fromCassini/VIMS solar occultation data

PRESSURE EFFECTS IN POLYCYCLIC AROMATIC NITROGENATED HETEROCYCLES (PANHs): DIAGNOSTIC QUALITIES AND COSMOBAROMETRY POTENTIAL

Contact Info

Product

Resources

About