Primary Mirror

* Effective diameter (diameter of light affecting area): 8.2 m (27 ft.)
* Thickness: 20 cm (7.9 inches)
* Weight: 22.8 metric tons (25.1 tons)
* Material: ULE (ultra-low thermal expansion glass)
* Mean Surface error: 12 nanometer (1/5,000,000 inch)
* Focal length: 15 m (49'2")

Telescope Structure

* Mounting: altitude-azimuth (Alt-Az)
* Basic Optics: Ritchey-Chretian System
* Height: 22.2 m (73 ft.)
* Maximum width: 27.2 m (89 ft.)
* Weight: 555 metric tons (612 tons)
* Foci: Four
-Primary focus: F2.0 (with corrector lens)
-Cassegrain focus: F12.2
-Nasmyth focus (optical): F12.6
-Nasmyth focus (infrared): F13.6
* Maximum slewing speed: 0.5 deg/sec
* Tracking accuracy without guiding: 0.1"
* Blind pointing accuracy: less than 1.0"
* Best angular resolution achieved: 0.2"
(without adaptive optics @ 2.15 μm)

Telescope Enclosure

* Altitude: 4139 m (13,580 ft.)
* Latitude: 19d 49m 32s N (based on NAD83)
* Longitude: 155d 28m 34s W (based on NAD83)

* Cylindrical enclosure rotating with the telescope
* Height: 43 m (141 ft.)
* Diameter at base: 40 m (131 ft.)
* Weight: 2000 metric tons (2205 tons)
* Outer wall: aluminum panels

Photos of Subaru Telescope and Enclosure

Subaru's Four Foci

Click here for the image without labels.


1) Prime Focus
Instruments designed to take advantage of the large field of view at prime focus

Fiber Multi-Object Spectrograph (FMOS)
Subaru Prime Focus Camera (Suprime-Cam)

2) Nasmyth Focus (Optical)
Heavy instruments such as high resolution spectrographs

High Dispersion Spectrograph (HDS)

3) Nasmyth Focus (Infrared)

Infrared Camera and Spectrograph (IRCS)
188-Element Adaptive Optics (AO)

4) Cassegrain Focus
A variety of instruments tailored to a wide range of research goals

Multi-Object Infrared Camera and Spectrograph (MOIRCS)
Faint Object Camera and Spectrograph (FOCAS)
Cooled Mid-Infrared Camera and Spectrograph (COMICS)

Former Generation Instruments

OH-Airglow Suppressor/Cooled Infrared Spectrograph and Camera for OHS (OHS / CISCO)
Subaru Adaptive Optics System (AO)
Coronagraphic Imager with Adaptive Optics (CIAO)

Guidelines for use

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