Regular Open Course

Regular Open Course

The open time is 10:00 a.m. to 5:00 p.m. (the admission is until 4:30 p.m. ).

It is free to look around inside the visitor course (it will take about 1~2 hours). You can visit every day except around New Year Days (Dec. 28 to Jan. 4). There is no explanation by staff.

However, during weekends, national holidays, and summer and spring vacation, the guide staff gives the explanation at Observatory History Museum.

Visiting the Regular Open Course is not required to apply in principle. However, it is required to apply in advance in case of group tours.

In addition to free visiting, we have guide tour (four times a month), stargazing party (twice a month), and 4D2U Dome Theater Show (twice a month).


  • Visitor will be given a badge at the entrance. Please wear your badge in a visible place.
  • Please not to enter the areas and facilities that are not opened for public. Be careful mosquitoes, bees, snakes and etc.
  • Please not to eat and drink inside the facilities except resting room. Please bring back the garbage by yourself.
  • Smoking is prohibited inside the campus except smoking area.
  • Please follow the instructions by staff or on guide signs inside the campus.
  • The National Astronomical Observatory of Japan is a research institute. Please not to come to the open course in the campus with pets. Assistance dogs (service dog, guide dog, and so on) are allowed in the campus.
  • National Astronomical Observatory of Japan is working on conservation vegetation. Let's keep the rich nature in the campus.
  • Hornets become active during the summer and fall. In the regular open course, hornets are found frequently every year. If you find some hornets, leave the location quietly and do not aggravate them. A tiger keelback (a poisonous snake) has also been reported. Please do not enter the grassy areas.

Mitaka Open House Day (Mitaka Star and Universe Day)

Once a year, the Mitaka campus holds special open house day. At that day, we have many programs such as opening the non-open facilities and laboratories for public, giving special lectures, exhibition of the results of latest astronomy, stamp rally that families can enjoy and so on. Also, at the time of sunny, we would hold stargazing party with 50 cm telescope for public outreach.

From 2009, we changed the name of the day from "Special Open House in Mitaka" to "Mitaka Star and Universe Day", and held with more variety contents.