Sanjay Limaye1* Johan
Warell2, Bhuwan C. Bhatt3, Patrick M.
Fry1 and Eliot F. Young4
Abstract. Observations of Venus were
made during 3 May to 11 May
2004 (117.4o - 125.7o phase angle) and 3 July to
10 July, 2004 (132.5o - 125.1o
phase angle) from the 1.2-metre Mt. Abu Telescope at Gurushikhar,
Himalayan
Chandra Telescope at Mt. Saraswati, Hanle and the Nordic Optical
Telescope at
La Palma, Canary Islands and the NASA/Infra Red Telescope Facility
(IRTF)
at Mauna Kea, Hawaii in J and K bands. While the sunlit crescent portion
was saturated in the detector, the night-side shows discrete cloud
features.
These features are seen to evolve over time and are markers of the
atmospheric
flow at tilda 53 km altitude above the surface. By combining
multi-site
observations, we are able to make measurements of zonal cloud velocities
over
baselines that are several hours long and get a better idea of the
evolution of
the features over time.
Keywords: Venus night-side; near infrared,
atmosphere circulation
1Space Science and Engineering Center,
University of Wisconsin, Madison, WI 53706, US
2Department of Astronomy and Space Physics, Uppsala
University, Uppsala, Sweden
3Centre for Research and Education in Science and Technology,
Indian Institute of Astrophysics,Hosakote, India
4outhwest Research Institute, Boulder, Colorado,
USA