Frequently Asked Questions

 

Q 1 : Why is the Subaru Telescope called Subaru ?

A 1 :
During the planning phase of the new National Astronomical Observatory of Japan (NAOJ) telescope, it was known as the Japan National Large Telescope, or "JNLT." When construction of the telescope began in 1991, the NAOJ advertised for a more interesting name for the telescope in Japan. The name chosen from about 3,500 applications was "Subaru." "Subaru" means a Japanese name of the Pleiades.

 

Q 2 : What is most significant about the Subaru Telescope?

A 2 :
The role of an astronomical telescope is to gather faint light from celestial objects using a mirror (or lens) and direct the concentrated (focused) light into one or more astronomical instruments. The "primary" mirror of the Subaru Telescope is made from an ultra-low thermal expansion glass 8.3 meters in diameter. This is the largest single-piece mirror in the world. In addition, the surface mean error of Subaru Telescope's primary mirror is 12 nm (nm= one billionth of a meter).

(Note that we only use light falling on the inner part of the mirror, so we say that the Subaru Telescope has an effective aperture of 8.2 meters.)

 

Q 3 : Why do you build the Subaru Telescope at the summit of Mauna Kea in Hawaii?

A 3 :
The requirements for celestial observations are that the weather is good, the humidity is low, and the night sky is dark . The summit of Mauna Kea easily satisfies all these conditions, making it nearly ideal for astronomical observing.

 

Q 4 : I would like to use Subaru images on my personal web pages.

A 4 :
You can freely use Subaru images on this web site for personal use. But "personal use" does not include the use of images on a personal web site if that web site is open to the general public. You are not allowed to use Subaru images on your personal web pages.

 

Q 5 : I would like to link my personal web page to the Subaru web site.

A 5 :
You may only link to a top page http://www.naoj.org/index.html freely. Please do not directly link to any images on this web site. Please refer to this page for the details.

 

Q 6 : I would like to visit the Subaru Telescope.

A 6 :
We are happy to announce that we will be offering guided tours of the telescope on the summit of Mauna Kea beginning October 1. Please read the "Visiting the Subaru Telescope" page. We also have a staff presentation program at the Hilo Base Facility.

 

Q 7 : Where do you control the Subaru Telescope?

A 7 :
We operate the Subaru Telescope from its control building located right beside the Subaru enclosure at the summit of Mauna Kea. If people were to stay within the enclosure, the turbulence created by any heat given off would have a bad influence on the observation. Therefore, we do not enter the enclosure when we are observing.

 

The enclosure and control building (bottom-right)

 

 

 

Q 8 : Can you control the Subaru Telescope from Japan?

A 8 :
Operation of the Subaru Telescope from the base facility in Hilo, Hawaii has been successfully demonstrated, though we still do our observing from the summit. In the future, we plan to control the Subaru Telescope from the Mitaka campus of the National Astronomical Observatory in Japan.

 

Q 9 : I would like to know employment opportunities.

A 9:
Please see the contact information page.

 

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