National Astronomical Observatory of Japan

Scientific Goals and Missions - Subaru Telescope


In order to explore the universe in the era of first galaxies and to reveal exoplanets shrouded in mystery, the Subaru Project at NINS/NAOJ provides to the scientists in Japan and other countries the observing data taken through Calls for Proposals with the Subaru Telescope, which is a large optical-infrared Telescope with an effective 8.2-meter diameter, located at the summit of Maunakea, Hawai‘i, USA.


The missions of this project are:

  1. to provide a stably operational telescope, maximize the availability of observing time, and make the operations user-friendly to facilitate science for broader communities;
  2. to collect and deliver high-quality data sets to the scientific community by operating, maintaining and further developing a state-of-the-art observatory; and
  3. to produce outcomes to meet the scientific requirements from broader fields of research and obtain fair evaluation from the scientific community.

Primary Scientific Goals

The primary scientific goals of this project are:

  1. to study the formation process of celestial objects through the observation of the early universe, less than one billion years after the Big Bang. For this purpose, we observe the distant galaxies during the epoch of reionization using Hyper Suprime-Cam (HSC);
  2. to study the origin of the large-scale structure of the universe by conducting very wide field deep survey of the universe. In particular, we reveal the distribution of dark matter in detail by conducting very wide-field survey of the distant universe using HSC and Prime Focus Spectrograph (PFS);
  3. to directly observe extrasolar planets and to study their characteristics and properties. As a first step, we directly observe Jupiter-like extrasolar planets to investigate the atmosphere of those planets using Coronagraphic High Angular Resolution Imaging Spectrograph (CHARIS), and detect earth-like extrasolar planet(s) by performing precise radial velocity measurement of stars lighter than the Sun using Infrared Doppler Spectrograph (IRD);
  4. to evolve multi-messenger astronomy in synchronization with gravitational waves and neutrino observations. In particular, we explore the origin of heavy elements and ultra high energy cosmic rays through the observations of neutron star or black hole mergers and neutrino bursts in cooperation with gravitational wave telescopes, high energy neutrino detectors, and other wavelength telescopes; and
  5. to study the formation process of a planetary system through the observation of its formation sites. In particular, we observe the formation sites of planetary systems and newborn planets using High Contrast Instrument for the Subaru Next Generation Adaptive Optics (HiCIAO).

Target Date

End of March 2022