Abstract
Institute of Astronomy, University of Tokyo is promoting a project called TAO (University of Tokyo Atacama Observatory; Yoshii et al. 2010) to construct a 6.5 m infrared telescope on the summit of Cerro Chajnantor (5640 m altitude) at Atacama desert in northern Chile. For the evaluation of the site characteristics, we first conducted weather and cloud emissivity monitoring and seeing measurement in 2006-2007. The clear fraction was high as >80% and the median seeing in the V-band low as 0."69. A 1 m pathfinder telescope called miniTAO was installed and started observation in 2009. We have successfully obtained 1.875 μm hydrogen Paα images as well as 30-40 μm images for the first time from a ground-based telescope. These results demonstrate that the summit of Cerro Chajnantor is one of the best sites for the infrared astronomy on the Earth.
