Laboratory Studies of Ammonia Ices Relevant to the Jovian Atmosphere

Mathematics – Logic

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

5799 General Or Miscellaneous, 6220 Jupiter, 6299 General Or Miscellaneous

Scientific paper

Ammonia ice condensation and cloud formation microphysics are topics of relevance for understanding the atmospheres of the giant planets. Ammonia ices are also considered important components of the icy satellites found in the outer solar system, and are thought to play an important role in their geological activity. Although observational evidence and thermochemical models suggest ammonia clouds in the Jovian atmosphere should be ubiquitous, less than only 1% of Jupiter's atmosphere appears covered by spectrally identifiable ammonia clouds, with a clear preference in turbulent regions.1,2 The paradox of the rather scarce spectroscopic signatures of ammonia clouds and their appearance in turbulent regions suggests that the nascent ammonia clouds may undergo processing that modifies their spectroscopic properties. No relevant laboratory experimental results are available to resolve this problem. Two possible sources of processing that have been suggested in the literature include photochemical solid-state modification (''tanning'') and coating of ammonia particles by other substances present in the stratospheric haze.2,3 We are performing laboratory investigations with the objective to provide information on the photophysical and chemical processes that control the optical properties of the Jovian ammonia clouds. In the experiments, thin ice films of ammonia are coated with organic molecules, such as saturated and aromatic hydrocarbons, and characterized by infrared spectroscopy. Preliminary results indicate suppression of the ammonia absorption feature at 2.7 μ m by a thin layer of hydrocarbons. The implications for the spectral signatures of ammonia clouds in the atmospheres of Jupiter and Saturn will be discussed. Funding from the NSF Planetary Astronomy Program under grant AST-0206270 is gratefully acknowledged. The participation of Rhiannon Meharchand and Christina Baer was made possible by the NSF Research Experiences for Undergraduates Program under grant PHY-0353745. 1. S. K. Atreya and A.-S. Wong, Eos. Trans. 84(46), Fall. Meet. Suppl., Abstract A12A-0072 (2003), and references therein. 2. K. H. Baines, R. W. Carlson, and L. W. Kamp, Icarus 159, 74 (2002). 3. A.-S. Wong, Y. L. Yung, and A. J. Friedson, Geophys. Res. Lett. 30, 1447 (2003).

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

Laboratory Studies of Ammonia Ices Relevant to the Jovian Atmosphere 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 Laboratory Studies of Ammonia Ices Relevant to the Jovian Atmosphere, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Laboratory Studies of Ammonia Ices Relevant to the Jovian Atmosphere will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1454255

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