Akeno Observatory


The Akeno Observatory started in April 1977. At the Akeno Observatory, extremely high-energy cosmic rays with energies exceeding 1020 eV were observed by the AGASA (Akeno Giant Air Shower Array) experiment. The AGASA had been in operation as the world's largest air-shower array for 13 years since 1990, but was terminated in January 2004, while handing over the observation to its larger scale hybrid successor Telescope Array (TA) in Utah, USA. The observatory is now used for observations of candidate sources of high-energy cosmic-ray acceleration such as Gamma Ray Bursts and Active Galactic Nuclei, research for variation of intensity of galactic cosmic rays, the support of TA, the tests of new devices related to the observations of high energy cosmic rays/gamma rays and the use by university collaborators in associated fields.


Address : 5259 Asao, Akeno-cho, Hokuto-shi, Yamanashi,
408-0201 Japan
TEL : +81-551-25-2301
FAX : +81-551-25-2303
Land : 18,469 m2
Building : 2,843 m2
Altitude : 900m (average atmospheric pressure: 910 hPa)


  • Nirasaki Sta. of JR Chuo Line → Taxi (25 min.)