Physics
Scientific paper
Dec 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006agufm.p41c1301l&link_type=abstract
American Geophysical Union, Fall Meeting 2006, abstract #P41C-1301
Physics
5704 Atmospheres (0343, 1060), 5754 Polar Regions, 5794 Instruments And Techniques
Scientific paper
On 2006 September 2-3, and 3-4, Uranus and Neptune were imaged at thermal wavelengths using the VISIR mid-infrared camera/spectrometer on the Very Large Telescope UT-3, "Melipal". A single image of Uranus was made at a filter centered at a wavelength of 18.6 microns, a part of the spectrum dominated by collision- induced hydrogen opacity, sensitive to upper tropospheric temperatures near 90-120 mbar total pressure. Similar images of Neptune were made with filters dominated by hydrogen opacity, centered at wavelengths of 17.6 and 18.6 microns, sampling temperatures near 60-100 mbar and 90-120 mbar total pressure, respectively. In addition, images of Neptune were obtained near (i) 8.6 microns, which is sensitive to a product of the temperature and methane mixing ratio in the lower-pressure stratosphere, and (ii) 12.2 microns, which is sensitive to a product of the temperature and ethane mixing ratio in the stratosphere. The temperature field of Uranus shows a warm low-latitude region, with a region around the south pole which is equally warm and a region around the north pole which is cooler than its southern counterpart. The meridional distribution of temperatures is qualitatively similar to Voyager infrared results. Neptune provided the biggest surprises, displaying a concentration of warm tropospheric temperatures, and stratospheric temperature-times-methane or ethane products at the south pole. The distribution of upper tropospheric temperatures is qualitatively different from the Voyager infrared observations, in which equatorial and polar temperatures were higher than those of mid-latitudes but were nearly equally warm. We also detected meridional variability in the methane- temperature and ethane-temperature products in the south polar region. The surprising amplitude of warm temperatures at the south pole requires examination to determine whether it is the weakest link in the cold trapping of methane from the stratosphere and the primary mechanism for convective migration of methane from its reservoir in the deep atmosphere.
Encrenaz Th.
Leyrat Cedric
Orton Glenn
Pantin Eric
No associations
LandOfFree
Spatially Resolved Thermal Infrared Observations of Uranus and Neptune from the ESO Very Large Telescope in September, 2006: Unexpected Meridional Distribution and Possible Zonal Variability of Upper Tropospheric and Stratospheric 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 Spatially Resolved Thermal Infrared Observations of Uranus and Neptune from the ESO Very Large Telescope in September, 2006: Unexpected Meridional Distribution and Possible Zonal Variability of Upper Tropospheric and Stratospheric, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spatially Resolved Thermal Infrared Observations of Uranus and Neptune from the ESO Very Large Telescope in September, 2006: Unexpected Meridional Distribution and Possible Zonal Variability of Upper Tropospheric and Stratospheric will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-962062