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Date: 09/19 (Thu)
Time: 14:45-16:30
Place: Cosmo Studio
Speaker: “Sugiyama Haruki"

Title:
"Multi spectral imaging for estimation of Uranus’s seasonal change ”

Abstract:
Uranus is the seventh planet of the solar system. This planet has unique features not found on other planets. It is a highly inclined axis of rotation. The axis of rotation is tilted about 98 degrees relative to the ecliptic plane, causing extreme seasonal changes in Uranus. In the summer, the sunlight near the North Pole is lit all day long, and it never hits in the winter. Such extreme changes in solar radiation are thought to bring about changes in Uranus's atmospheric circulation, but this has not been fully elucidated.
In the meantime, Uranus was considered to be a planet without characteristics like clouds and no change compared to other planets such as Jupiter. However, structures such as methane clouds have been discovered by the 1986 Voyager 2 approach and recent HST observations with large telescopes. Furthermore, it has been found that the brightness of Uranus at every latitude also changes over time. These changes are thought to be due to changes in the structure of the atmosphere due to changes in solar radiation, but are not yet clear.
However, large telescopes and space telescopes are difficult to observe, and many observations have been done once a year, only a few days. There are not many observations on a weekly and monthly basis.
Therefore, in this research, we will make use of the rich machine time of the Pirka telescope and conduct multi-wavelength observations at an unprecedented frequency to confirm whether Uranus changes with time on a weekly or monthly basis.
We also consider longer seasonal changes in units of several years compared to past observation cases.
The goal of my research is to capture the temporal change of the methane cloud, which is thought to be composed of the bright structure and the methane ice currently found in Uranus' polar regions. Therefore, my imaging is performed at wavelengths with and without methane absorption, and the temporal change in brightness at each latitude of Uranus.
 In the presentation, I will introduce the observation and analysis that I want to perform.
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