Publications of the MPIfR
Optical & Infrared
Interferometry Group
Kostiuk, T.; Livengood, T. A.;
Sonnabend, G.; Hewagama, T.; Fast, K.; Annen, J.; Tokunaga, A.;
Murakawa, K.; Schmülling, F.
Update on Titan's Stratospheric Winds Before
and During Huygens Entry Epoch
American Astronomical Society
DPS meeting #37, #51.09
Bulletin of the American Astronomical Society, Vol. 37, p.735 (2005)
Abstract
Results from recent analyses of regional wind fields on Titan will be
presented. Comparison of retrieved winds from infrared heterodyne
measurements at the 3-meter NASA IRTF (1993-1996) and from the
8.2-meter Subaru telescope of the National Astronomical Observatory of
Japan (Dec. 2003, Jan. 14-15 2005) will be made. Wind fields were
determined from Doppler shifts of 11.7 micron ethane emission lines
from Titan's stratosphere, measured at λ /δ λ = 1,000,000 resolving
power using pre-Cassini Huygens atmospheric models and available ethane
molecular line parameters (line intensities, frequencies, and
identities). Prograde wind velocities of ∼ 200 m/s were retrieved at ∼
200 km altitudes. These data will be reanalyzed using Titan's
near-equatorial thermal profile retrieved from Cassini CIRS
measurements and ethane line intensities and frequencies, including
weaker and ``hot" band transitions, retrieved from recent laboratory
spectroscopic studies at comparable spectral resolution. A discussion
will be presented on the measurements made around the period of Huygens
descent and what the obtained unexpected spectral shapes tell us about
the wind structure on Titan.
You can get this publication ...