Australian Sky & Telescope - June 2018

18 AUSTRALIAN SKY & TELESCOPE July 2018

sites for a new 150-inch (or, in today’s

parlance,4-metre)classtelescopein

theSouthernHemisphereduringthe

late 1960s, Siding Spring was considered

tobethebestplaceinAustralia.Work

onthetelescopebeganinearnestin

1969,andfromthemomentHRH

Prince Charles arrived at Siding Spring

Observatoryto‘declarethisaperture

open’onOctober16,1974,the

AAT’searlyhistorywasunashamedly

triumphal.Itwasbyfarthebiggest

telescopeavailabletoBritishand

Australian astronomers. Moreover, the

pioneeringcolourimageryofDavid

Malintookitfirmlyintothepopular

media, and early electronic detectors

such as the Image Photon Counting

System reaped an enviable harvest

ofscientificdiscovery.Alongsideit,

thewide-angleUKSchmidtTelescope

(openedonAugust17,1973)was

producing the most significant

photographic atlas of the southern sky.

Fromthebeginning,theAAO’s

Sydney-based scientists and engineers

showed themselves to be adept at

building novel instruments for use with

theAAT.Itwastheearlyuseofoptical

fibres, however, that set the Observatory

on its current course. The idea of using

fibrestopipethelightofstarsand

galaxies into auxiliary instruments was

notactuallyinventedatAAO.However,

it was transformed from an interesting

noveltyintoahighlyproductive

techniqueatboththeAATandthe

UKST during the early 1980s.

Thetechniqueisknownas‘multi-

fibre spectroscopy’, and it enables

detailed measurement of the vital

statistics of target stars or galaxies,

hundredsatatime,inlarge-scale

‘populationcensus’-typestudies.Pilot

spectroscopic surveys on both telescopes

demonstrated its potential and, in

themid-1990s,theAAOunveiled

2dF(for2-degreeField)ontheAAT.

This ground-breaking instrument

enabledthespectraof400objectsto

be obtained simultaneously using fibres

positionedroboticallyina2-degreefield

ofview—anunprecedentedfieldof

viewfora4-metreclasstelescope.

2dF’sfirsttaskwasathree-

dimensionalsurveyofthedistribution

ofgalaxieswithin2.5billionlightyears

to provide a detailed cross-section of

the Universe. The project measured

221,000 galaxies and was completed

in2002,quicklybecomingoneofthe

richest sources of AAO scientific papers

todate.In2005,itwasusedtofindthe

‘missinglink’betweenthetemperature

fluctuationsintheCosmicMicrowave

Background Radiation — the ‘flash’ of

theBigBang—andtoday’sdistribution

of galaxies.

Building on this achievement, the

AAObuiltasuccessionofroom-sized

instrumentstobefedremotelyby2dF,

culminatingin2014withHERMES,

ahigh-resolutionspectrographthat

wasespeciallydesignedtoinvestigate

thehistoryofourGalaxyusing

detailedobservationsoflargenumbers

of individual stars. The ‘Galactic

ArchaeologywithHERMES’(GALAH)

project has already netted the spectra

ofhalfamillionstars.Anotherrecent

innovative instrument is the Sydney-

AAO Multi-Object Integral field

spectrograph, or SAMI, which deploys

multiple fibres for the detailed study of

nearby galaxies.

OBSERVATORIES

S HISTORIC DAY The then Minister for

Industry, innovation and Science, Arthur

Sinodinos, and the then Director General of

ESO, Tim de Zeeuw, signed a Partnership

Agreement between Australia and ESO in

July 2017.

T AUSSIE INGENUITY The OzPoz ibre

positioner was built by the Australian

Astronomical Observatory for the FLAMES

multi-object spectrograph used by ESO’s Very

Large Telescope. A robotic arm accurately

places optical ibres into position to pick

up the light of selected galaxies or stars.

This example of Australian know-how going

overseas is likely to be repeated under the

new strategic partnership with ESO.

DIIS; ESO