Large Optical Telescopes 8-10m & 23-39m

Atualização: 20/04/2017

Giant telescopes

2 Fig. 1.8, Lena, 3rd Ed.

GMT

VLT, Gemini, etc

Giant telescopes

3

GMT, TMT, ELT

Natu

re 4

52, 142-1

45 (

2008)

39 m

Giant telescopes ● The construction of telescopes with large mirror faces difficulties

● Solutions

⇨ very thin mirrors

⇨ mosaic of mirrors

→ Keck: 10m = 36 x 1,8m

→ Support for each mirror (active optics)

The 10 meter Keck telescopes were developed and built by CALTECH & Universidade de California. What about USP?

Giant telescopes : Keck 10m

In front of a mirror segment of the Keck telescopes (2003)

in Mauna Kea mountain (Hawaii, USA) at 4205 m

Swinburne's Centre for Astrophysics & Supercomputing (Australia) staff

and students mark out the size of one Keck mirror. They have an

agreement to use up to 20 nights of Keck time. http://astronomy.swin.edu.au/keck/

Giant telescopes : 2 x Keck 10m

- Australia has 15 nights per year. Also: - Swinburne University (Melbourne) has 15-20 Keck nights per year - The Australian National University (ANU) has 15 nights per year (new director of ANU Research School of Astronomy & Astrophysics). ANU = budget$886milhões? = R$1,8

bilhões

- USP = 0 noites (budget R$5 bilhões)

GTC

HET

Las Campanas Pachon Roque de Los

Muchachos, La Palma

McDonald, Texas

Mt Graham, Arizona

Hawaii

Hawaii Hawaii

Mt. Hopkins,

AZ Hawaii

La Silla Siding

Spring

Australia

La Silla

3,6m

Blanco

4m

To

lolo

Paranal

SOAR

Pachon

Updated by J.M. on May 2nd, 2012

Kitt Peak Hawaii

La Palma Hawaii

Kitt Peak La Palma

Apache

Point, NM

Partners: Australia Limited (AU universities), ANU, Carnegie, Harvard, Korea ASI,

SAO, Univ. Texas, Texas A&M, Univ. Arizona, Univ Chicago, FAPESP

Artistic image of GMT

at Las Campanas

FAPESP no GMT, 4% cost (<= 14 nights)

Cerro Las Campanas, 2550 m above sea level

• 7 X 8.4m Segments

• 18m focal length

• f/0.7 primary

• f/8 Gregorian focus

• 21.4m equiv. area

• 24.5m equiv. ang. res.

• 20-25’ FOV

The Giant Magellan Telescope

(GMT) 21,4 – 24,5m

7 x 1.1-m secondary segments

•Cost in 2008, US$600 million, cost as of May 2012, US$700 million.

Cost as of April 2016: 1 billion US$?

•Completion target in 2008 2017; in 2016 2021; in 2017 2022

•Location - Las Campanas Observatory, Chile (2,516 meters)

•Height of telescope housing - 200 feet (61 meters)

The second of GMT’s seven 8.4 meter (27-foot) diameter primary mirrors was cast on 2012

January 14th at the University of Arizona's Steward Observatory Mirror Laboratory.

GMT Press Release (April 2, 2012)

GIANT TELESCOPE PROJECT PARTNERS

PASS ON FEDERAL FUNDS Pasadena, CA --The board of directors of the Giant

Magellan Telescope Organization (GMTO) has informed

the National Science Foundation (NSF) that they will not

participate in an upcoming funding opportunity. The

partners in the project feel that they are making such

rapid progress that they have chosen to press ahead at

full speed, looking to link up with the NSF at a later date.

With nearly half of the $700M needed to build the

observatory committed, the partners are confident that

they will complete the telescope.

GMT Press Release (March 23, 2012)

BIG BANG ON EARTH - BLASTING A

MOUNTAINTOP TO MINE THE SKY Astronomers have begun to blast 3 million cubic feet of rock from a

mountaintop in the Chilean Andes to make room for what will be the

world’s largest telescope when completed near the end of the decade.

The telescope will be located at the Carnegie Institution’s Las Campanas

Observatory - one of the world’s premier astronomical sites, known for its

pristine conditions and clear, dark skies. Over the next few months, more

than 70 controlled blasts will breakup the rock while leaving a solid bedrock

foundation for the telescope and its precision scientific instruments.

The TMT: 30-Meter

Telescope

The TMT Conceptual Design

• 30-meter filled aperture mirror

• 492 segments of 1.4m diameter

• Alt-azimuth mount

• Ritchey-Chrétien design

• f/1 primary, f/15 final focus

• Very AO-intensive

• Field of View = 20 arcmin

• Instruments located at Nasmyth

foci, multiple instruments on each

Nasmyth platform addressable by

agile tertiary mirror

First light: 2008 estimate 2016; 2012 2018;

2013 2021; 2015 2022 (perhaps 2023?)

The TMT project is an international partnership among Caltech, the University of California, and the Association of Canadian Universities for Research in Astronomy. The National Astronomical Observatory of Japan (NAOJ) joined TMT as a Collaborating Institution in 2008. The National Astronomical Observatories of the Chinese Academy of Sciences joined TMT as an Observer in 2009. India joined as an observer in 2010. China and India became TMT partners in 2012 COST in 2008: US$754 million COST in 2009: US$1 – 1.2 billion COST in 2013: US$1.3 billion COST in 2016: US$1.4 billion

Artistic image, TMT @ Mauna Kea

700 crore proposed budget

1 crore = 10 million Indian rupees

700 crore = 132 million US$

India gets money for the TMT

Cultural practitioner Joshua Lanakila Mangauil, along with Kahoʻokahi Kanuha and Hawaiian

sovereignty supporters block the access road to Mauna Kea in October 2014, demonstrating

against the building of the Thirty Meter Telescope. https://www.flickr.com/photos/occupyhilo/15489459316/in/photostream/

Aperture: 42 m

Field of view: 10 arcminute diameter

Mounting: Nasmyth mount

Location: Cerro Armazones, Chile @ 3060 m

Housing: Dome

Start of operations:

2018 (planned)

Wavelength range:

blue atmospheric cut-off (300 nm) to mid-infrared (24 microns)

Instrumentation: 9 stations for fixed instruments

Pixel scale: at Nasmyth focus (F/17.7), 1 arcsecond on sky corresponds to 3.6 mm in the focal plane

European

Extremely Large

Telescope (E-ELT)

39,3 m (798 hexagonal 1.4 m mirror segments)

Early next decade

Cost about 1 billion euros

E-ELT and VLT vs Giza Pyramids

GMT = 5 Keck

TMT = 9 Keck

ELT = 15 Keck K

ec

k (1

0m

)

GMT

(23m) TMT (30m)

ELT (39,3 m)

8 m

SO

AR

OP

D

http://www.eso.org/public/brazil/news/eso1440/

December 2014: Green light to construct the ELT

Why was the two-phase approach necessary?

A: The two-phase plan allows ESO to move ahead with the

construction while awaiting the completion of the Brazilian

ratification process. The ESO Council requires ESO to have

90% of funding secured before starting construction. To comply

with this rule and also to respect the timing of the project, a

decision was taken to divide the work in two steps.

Even though a Phase 1 E-ELT will be a fully working 39-metre

telescope with adaptive optics and three science instruments,

ESO’s goal remains to secure funding for the full baseline E-ELT

that will provide an extraordinary telescope with further improved

performance and operational characteristics.

What will be moved to Phase 2?

A detailed list of the items moved to Phase 2 is given in the December

2014 Messenger article. A summary is given here:

210 out of a total of 798 mirror segments of the telescope’s primary

mirror. These constitute the five inner rings of the main mirror.

The seventh sector mirror segments: The E-ELT’s primary mirror is

composed of six identical sectors of 133 segments each. The 133

segments are different to each other both in shape and optical

prescription. The baseline plan foresees the procurement of a seventh

sector strictly needed to guarantee the replacement of the segments in

a turn-around plan to maintain a constant reflectivity and micro-

roughness level. This seventh sector is moved to Phase 2.

Two of the six lasers used for adaptive optics.

The LTAO (laser tomography adaptive optics) module: this affects the

performance of the METIS and HARMONI instruments, and is identified

as the highest priority Phase 2 item.

One of the pre-focal stations on the telescope’s Nasmyth platforms.

The power-conditioning system.

26/5/2017