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Date: 12/26 (Thu)
Time: 14:45-16:30
Place: 8-1-03
Speaker: Haruki Sugiyama
Title: Multi spectral imaging for estimation of Uranus’s seasonal variation

Abstract:
 Uranus is the seventh planet in the solar system, and time-varying structures such as methane clouds have been discovered by close-range exploration by Voyager 2 in 1986 and recent observations by HST and large ground-based telescopes. In addition, it has been found that the brightness of Uranus at each latitude also changes with time. These changes are thought to be due to changes in atmospheric circulation due to changes in solar radiation, but the mechanism is not yet clearly understood. In addition, large telescopes and space telescopes are difficult to take observation time, and most of the observations so far are once a year, only a few days. Weekly and monthly observations are rarely made.
The goal of this time is to capture the temporal change of the methane cloud, which is thought to be composed of methane ice and the bright structure currently found in the polar region of Uranus, on the unprecedented time scale using the abundant machine time of the Pirika telescope. is there. As a specific technique, imaging is performed at a wavelength at which methane is absorbed and at a wavelength at which it is not. Then, cloud changes are estimated from changes in the ratio of brightness for each wavelength of Uranus at each latitude.
In this presentation, I will introduce some of the observations that have been made to date and the analysis methods that will be developed.
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