Dodaira Observatory 'Star and Green Creation Center' - Full-Scale Stargazing at a Former National Observatory
Overview
Dodaira Observatory "Star and Green Creation Center" is an astronomical observation and accommodation facility located at the summit of Dodaira Mountain (875.8 meters elevation) in Tokigawa Town, Hiki District, Saitama Prefecture. It has a history of serving as an observation facility for Tokyo University's Tokyo Observatory (now the National Astronomical Observatory of Japan), and a 91-centimeter reflector telescope continues to operate there.
The major attractions are its convenient access from Tokyo (about 2 hours by car) and the availability of accommodation facilities.
Observation Environment
The summit of Dodaira Mountain has an open surrounding area, with particularly excellent views from the south and west. At an elevation of 875 meters and located at the border between the Chichibu Mountains and the Kanto Plain, a dark sky from the Chichibu direction spreads to the north.
However, from the south to east, there is some influence from light pollution from the Kanto Plain, so the darkness doesn't rival that of Hokkaido or Nagano highlands. Still, the sky is significantly darker than the metropolitan area, and on favorable nights, the Milky Way is visible.
Facilities and Equipment
The main feature is the 91-centimeter reflector telescope, which can be used during bimonthly celestial observation events. These events are reservation-based and include expert explanations.
Accommodation facilities include Mongolian tents, log houses, and bungalows, accommodating families and groups. As an overnight guest, you can enjoy stargazing throughout the night within the facility, allowing for dedicated observation time.
Access
About 50-60 minutes by car from Higashimatsuyama IC or Arashiyama-Ogawa IC on the Kan-Etsu Expressway. The access road to the summit is paved but has narrow sections, requiring caution with oncoming traffic. Public transportation access is difficult, so a car visit is essential.
Observation Tips
Check the official website for observation event schedules. Reservations are highly recommended as they are popular. Even without overnight accommodation, you can enjoy the starry sky from the summit parking area. The summit is often windy, so bring a windproof jacket.