Ginga-no-Mori Observatory (Rikubetsu), Japan — One of Japan's Largest Public Telescopes in Hokkaido's Star Town

Overview

Ginga-no-Mori Observatory (銀河の森天文台 / Rikubetsu Space and Earth Science Museum) is a public observatory in Rikubetsu-cho, Ashoro-gun, Hokkaido. Rikubetsu received the "Star-Friendly Town" designation from Japan's Environment Agency in 1987, and was further recognised in the "10 Towns Kind to the Starry Sky" list in 1997 — making it one of Japan's most consistently celebrated dark-sky communities.

The observatory's 115 cm reflector is among the largest telescopes available to the general public in Japan, and through it the universe becomes vivid in a way that smaller instruments can't approach.

Observing Conditions

Rikubetsu occupies Hokkaido's inland plateau, far from any significant city. Light pollution is extremely low. In winter, the continental high-pressure system delivers frequent clear skies with exceptional transparency — cold air holds very little moisture, and the stars are startlingly sharp. Low-latitude aurora events have also been observed here on rare occasions.

The elevation of about 340 m isn't dramatic, but the flat surrounding terrain keeps the horizon clear in all directions. On the right night, the Milky Way is as good here as anywhere in Japan.

Facilities

Alongside the flagship 115 cm reflector, the observatory operates two 30 cm reflectors, a 25 cm reflector, and a 4-unit solar telescope. Daytime visitors can watch sunspots and solar prominences; evening sessions deliver guided tours of seasonal objects with staff commentary. The planetarium and earth-science exhibits provide a complete experience even when clouds interfere — which they sometimes do.

Access and Practical Info

About 2 hours by car from Obihiro; roughly 2 hours 30 minutes from Tokachi-Obihiro Airport. Car (or rental car) is essentially required — public transit is very limited. Winter road surfaces can be seriously icy; check conditions before driving.

Open Wednesday through Sunday and holidays (closed Monday and Tuesday). Summer hours: 14:00–22:30; winter hours: 13:00–21:30. Observing sessions require no reservation for individuals; groups should contact in advance. Parking is free.

Observing Tips

Rikubetsu is one of Japan's coldest towns — temperatures drop below -20 °C in winter. This is not an exaggeration. Full winter gear is absolutely essential: hand warmers, insulated gloves, a down jacket, and a hat. Eyepieces can fog over when brought from the cold; keep a lens cloth handy. Summer is far more comfortable and excellent for Milky Way viewing, though insect repellent is necessary. Spring and autumn are ideal for galaxies and star clusters.