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NAOJ TMT Project Office / New Home Page

August 6, 2010

The new home page of NAOJ TMT Project Office is now available.
Please visit
the new home page (NAOJ TMT Project Office)
to access our latest activities.

Here is the previous concept of Japanese ELT project before 2006.

To explore fainter objects with higher resolving power... This has been a limitless dream of astronomers. The last decade of the 20th century was an exciting era for such astronomers. More than ten 8-10m telescopes have been constructed at excellent sites for observing. Highly efficient detectors for optical and infrared observations have enabled great progresses in understanding of star formation, structure of the universe, etc.

Such innovations achieved discovery of galaxies and Gamma-ray bursts at very high redshift, which are objects in an era of the re-ionization of the universe, and detection of formation sites of extra-solar planets. However, new discoveries also have been bringing new mystery. Now observing with higher efficiency and higher resolving power is desired for further understanding of the universe.

Japan Extremely Large Telescope is proposed as a next generation ground-based telescope. This plan is aiming at construction of 30m-class telescope, which is nearly four times larger in diameter than Japan's largest telescope Subaru.

The ELT project group started its activity from April 2005 as a first phase (phase A) project at National Astronomical Observatory of Japan. The project group has been conducting development of new technology for future optical and infrared telescope by collaborations with astronomers and engineers in universities.

Activities since 2005 . . .

1) development of ultra-high precision grinding system for segmented mirrors
2) development of zero-expansion pore-free ceramic (ZPF) as a new materials for segmented mirror
3) design of three aspherical surface optical system
4) detailed design of telescope structure
5) developments of sensors for mirror support and actuators
6) conceptual design for next generation adaptive optics system
7) planning observational instruments

last modified 2006/11/29

SPIE2006 (Orland)
IAU 232 (Cape Town)
Optical Design (pdf:566KB)
Nariai and Iye, PASJ, 57, 2005

Tokyo Shinbun (2003/4/15)
Daily Yomiuri (2001/6/6)

Copyright (c) 2006 Japan Extremely Large Telescope, NAOJ. All right reserved.
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