National Astronomical Observatory of Japan




The Nobeyama Radioheliograph is a radio telescope dedicated to solar observations. It has been operated by the Nobeyama Solar Radio Observatory since 1992. It consists of 84 small parabolas configured in a T-shaped array. The East-West arm is 490 m and North-South arm is 220 m long. This telescope takes radio images of the Sun every 0.1 second during the daytime. The images are used by researchers all over the world for studies of the solar activities with wide range of timescales. Solar flares are the main research targets of the Radioheliograph. High-energy particles created in solar flares emit very strong microwaves that we can observe using this telescope and study the mechanisms of particle acceleration and also the causes of solar flares. With the Nobeyama Radioheliograph’s 20 years of data, we can detect solar activities with long time scales. We can observe not only activities associated with sunspots but also activities around North and South Poles. This instrument plays a very important role in the monitoring of long-term global solar activities.

Nobeyama Solar Radio Observatory is finished the project on March 31, 2015. And the Radio Heliograph is operated mainly by Nagoya University.


  • 462-2, Nobeyama, Minamimaki, Nagano 384-1305, Japan
  • +81-267-98-4498
  • Official Web Site