National Astronomical Observatory of Japan

Scientific Goals and Missions - Japanese VLBI Network (JVN)


The Japanese VLBI Network (JVN) project is to establish the observation network consisting of 30-meter-class radio telescopes located in Japan, aiming to develop the time-domain VLBI astronomy for high-mass protostars and high energy events.


The missions of this project are:

  1. to compile and deliver time-domain VLBI data catalogs to the scientific community utilizing large radio telescopes that have been operated and maintained by the respective university in Japan; and
  2. to nurture highly-skilled youths by offering opportunities for undergraduate/master/Ph.D. students to engage in not only extensive science activities but also productive educational programs including on-site observation experience.

Primary Scientific Goals

The primary scientific goals of this project are:

  1. to monitor more than 400 methanol maser sources with the JVN and to make the world’s largest monitoring catalog that reveals the structure and intensity variability;
  2. to observe 390 extreme-compact HII regions with the JVN, and identify the youngest HII regions out of them; and
  3. to make a catalog of radio sources for the possibly emitting gamma-ray by observing more than 1000 sources with the JVN.

Target Date

End of March 2022