Encyclopedia of the Solar System 2nd ed

TABLE

1

Telescopes with Apertures Greater than 5 Meters

(2)

(8)

Circular

(5)

(6)

Mirror

(9)

(1)

Aperture

(3)

(4)

Date of

primary

(7)

Aspect

Mounting

(10)

Aperture (m)

Equivalent (m)

Telescope Name

Location

Operation

f/no

Mirror Type

Ratio

Type

Ref.

2

×

8.4

11.8

Large Binocular Telescope (LBT)

Mt. Graham, Arizona

(2006)

1.14

Honeycomb

9.4

Alt-Az

1

11

×

9.4 Hexagon

10.0

Keck I

Mauna Kea, Hawaii

1993

1.75

Segmented

133

Alt-Az

2

11

×

9.4 Hexagon

10.0

Keck II

Mauna Kea, Hawaii

1996

1.75

Segmented

133

Alt-Az

2

11

×

9.4 Hexagon

10.0

Gran Telescopio Canarias (GTC)

La Palma, Canary Islands

(2007)

1.65

Segmented

125

Alt-Az

3

11

×

10 Hexagon

9.2

Hobby-Eberley Telescope

Mt. Fowlkes, Texas

1997

1.4

Segmented

200

Azimuth only

4

11

×

10 Hexagon

9.2

Southern African Large Telescope (SALT) Sutherland South Africa

2005

1.4

Segmented

200

Azimuth only

5

8.2

8.2

Subaru

Mauna Kea, Hawaii

1999

1.8

Meniscus

41

Alt-Az

6

8.2

8.2

Very Large Telescope (VLT) UT1 Antu

Cerro Paranal, Chile

1998

1.75

Meniscus

46

Alt-Az

7

8.2

8.2

Very Large Telescope (VLT) UT2 Kueyen Cerro Paranal, Chile

1999

1.75

Meniscus

46

Alt-Az

7

8.2

8.2

Very Large Telescope (VLT) UT3 Melipal Cerro Paranal, Chile

2000

1.75

Meniscus

46

Alt-Az

7

8.2

8.2

Very Large Telescope (VLT) UT4 Yepun

Cerro Paranal, Chile

2000

1.75

Meniscus

46

Alt-Az

7

8.0

8.0

Gemini North

Mauna Kea, Hawaii

1998

1.8

Meniscus

40

Alt-Az

8

8.0

8.0

Gemini South

Cerro Pachon, Chile

2000

1.8

Meniscus

40

Alt-Az

8

6.5

6.5

MMT Conversion

Mt. Hopkins, Arizona

1999

1.25

Honeycomb

9

Alt-Az

9

6.5

6.5

Magellan I - Walter Baade

Cerro Manqui, Chile

2000

1.25

Honeycomb

9

Alt-Az

10

6.5

6.5

Magellan II - Landon Clay

Cerro Manqui, Chile

2002

1.25

Honeycomb

9

Alt-Az

10

6.0

6.0

Large Zenith Telescope (LZT)

Vancouver, Canada

2005

1.5

Liquid Hg

n/a

Fixed

11

6.0

6.0

Bol’shoi Teleskop Azimultal’nyi (BTA)

Mt. Pastukhova, Russia

1977

4

Solid

6

Alt-Az

12

5.1

5.1

Hale

Mt. Palomar, California

1949

3.3

Honeycomb

8

Equatorial

13

References(1) http:// lbto.org/, (2) http:// http://www.keckobservatory.org//, (3) http://www.gtc.iac.es/, (4) http://www.as.utexas.edu/mcdonald/h

et/het.html, (5) http://www.salt.ac.za/, (6) http://www.naoj.org/,

(7) http://www.eso.org/, (8) http://www.gemini.edu/, (9) http://www.mmto.org/, (10) http://www.ociw.edu/magellan/magellan.html, (11) htt

p://www.astro.ubc.ca/LMT/,

(12) http://www.sao.ru/Doc-en/index.html, (13) http://astro.caltech.edu/observatories/palomar/This table is adapted from J.M. Hill’s web site: http://abell.as.arizona.edu/

∼

hill/list/bigtel99.htm.

Column (1). The aperture is the diameter of the primary that can collect light. Unless specified, the number given is the diameter of a circular aperture

. The LBT consists of two 8.4-m mirrors that are on a

single mount and the light from both mirrors are combined to form a single image. The Keck, HET, and SALT telescopes have primary mirrors that are made fr

om hexagonal segments. The primary mirror has

a hexagonal shape and the largest and smallest widths of the hexagon are given.Column (2). This is the diameter of the equivalent circular aperture equal to the total light collecting area of the telescope. For the HET and SALT tele

scopes this is the maximum equivalent circular aperture

that is accepted by the prime focus optics. The LBT, Keck, and VLT observatories can combine light from the mirrors for use as an interferometer. This mo

de of observations is not considered in this table for

the purpose of determining the equivalent circular aperture.Column (5). Year that science operations started. Parentheses denote year science operations expected.Column (6). Primary mirror f/no, which is equal to the focal length of the telescope divided by the mirror diameter.Column (7). Honeycomb: Primary mirror that is lightened with a honeycomb structure in the back. Segmented: Primary mirror is made out of hexagonal seg

ments. Meniscus: Single thin concave mirror.

Liquid Hg: Liquid mercury mirror. Parabolic shape is obtained by spinning the mirror. Solid: Thick mirror with no light-weighting.Column (8). The aspect ratio is the primary mirror diameter divided by the mirror (or segment) thickness.Column (9). The azimuth only and fixed telescope mounts conduct observations by tracking object in the focal plane of the telescope. For such telescope

s the telescope is fixed but the instrumentation tracks

the object.

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