| Page name or Wikidata label | |
| Organization: | University of Tokyo |
| Location: | Mount Ontake, Nagano Prefecture |
| Altitude: | 1130m (3,710feet) |
| Established: | 1974 |
| Telescope1 Name: | Unnamed |
| Telescope1 Type: | 105 cm Schmidt telescope |
| Telescope2 Name: | K.3T |
| Telescope2 Type: | 30 cm robotic telescope |
Kiso Observatory (Japanese: 木曽観測所: Kiso Kansokujo) is an astronomical observatory located at Mt. Ontake in Japan. The observatory was founded in 1974, originally as a branch observatory of the Tokyo Astronomical Observatory, with the express objective of studying extra-galactic astronomical objects.[1] Since 1988, it has been maintained by the Institute of Astronomy, Faculty of Science, University of Tokyo (Japanese: [[:ja:東京大学大学院理学系研究科附属天文学教育研究センター|東京大学天文学教育研究センター]]). It is home to the 105 cm Schmidt Telescope. It is currently open for use by astronomers from all over the world.
In 2002, a 30 cm, fully automatic telescope was added with the designation K.3T (Kiso 0.3-meter Telescope). It is mainly used in the observation of variable stars. It has been automated to aid in the making of numerous repeat observations over long periods of time.[2]