Spectroscopic and Imaging Observation of the Venus Atmosphere by a Balloon-Borne Stratospheric Telescope FUJIN-2

抄録

While Japanese Venus Climate Orbiter Akatsuki has made progress in studying Venusian atmospheric dynamics, the chemistry relevant to clouds and the atmospheric trace elements have not been fully elucidated. The key to solving these problems is ultraviolet (UV) absorbers, which are responsible for the characteristic albedo pattern in UV wavelengths at the cloud top altitude. Since these chemistries are coupled with solar radiation heating, it is important to identify the UV absorber(s). We are currently developing the FUJIN-2 balloon-borne telescope as a new platform for observing the solar system planets from the Earth's stratosphere with a wide wavelength range. FUJIN-2 is equipped with a precise three-stage attitude control and pointing system. A high spatial resolution comparable to a satellite telescope can be attained by even a 400-mm small telescope. The present study describes the status of FUJIN-2 development and introduces its observation plan of Venus by UV spectroscopy and high spatial-temporal imaging.