Titan's Aerosol and Stratospheric Ice Opacities between 18 and 500 μm: Vertical and Spectral Characteristics from Cassini CIRS

Physics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

[0343] Atmospheric Composition And Structure / Planetary Atmospheres, [6281] Planetary Sciences: Solar System Objects / Titan

Scientific paper

Cassini Composite Infrared Spectrometer (CIRS) spectra of Titan are utilized between 20 and 560 cm-1 (500 to 18 μm) to determine aerosol and stratospheric ice opacities, as well as vertical abundance distributions below 300 km. We derive broad emission features that peak at ~140 cm-1 for the aerosol and ~160 cm-1 for the ice at latitudes 15°N, 15°S, and 58°S. The ice feature spans 70 to 270 cm-1 and is restricted to altitudes between 50 and 100 km, where condensations of various nitriles are expected. This ice feature most likely stems from a composite of HCN and HC3N ices, which are the two most abundant nitriles in Titan’s atmosphere. We speculate that the aerosol emission feature arises from lattice vibrations of large 2D planar molecules, such as polycyclic aromatic hydrocarbons (PAHs) and/or nitrogenated aromatics. Between 400 and 560 cm-1, Titan’s aerosol spectrum resembles the spectrum of laboratory generated aerosol or tholin material (Khare et al., 1984, Icarus 60, 127-137), but rapidly diverges from the laboratory spectrum below 400 cm-1. The chemical composition of Titan’s aerosol does not appear to change with altitude or latitude, suggesting that the rates of formation and chemical evolution of the aerosol are lower than the rate of dynamical turnover for the atmosphere. This is not the case for the stratospheric ice composite, which appears to chemically change with altitude and latitude, due to differences in ice abundances and condensation temperatures.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Titan's Aerosol and Stratospheric Ice Opacities between 18 and 500 μm: Vertical and Spectral Characteristics from Cassini CIRS does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Titan's Aerosol and Stratospheric Ice Opacities between 18 and 500 μm: Vertical and Spectral Characteristics from Cassini CIRS, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Titan's Aerosol and Stratospheric Ice Opacities between 18 and 500 μm: Vertical and Spectral Characteristics from Cassini CIRS will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1494357

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.