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:
j:
AUXILIART INSTRUMENTS
V
AND AUTOXIATION
AUXTLIART INSTRUMENTS
Although the telescope is properly given greât emphasís.as.the single most
;;;"-"î iool of thå obrJ*"tiooJ"ttronomer, the anaþzing devices¡ athe nd
-riä
a link i
r^ii"rioo detectors at the focus of the telescope ale so vitâl
piocess of collecting and ilecoding the information being received from
astro-
scrutiny' 'A' review of current
ão*icaf ¡o¿i"t thai th"y deservã the closest
that very
f.u.ti"" "tta perfo.munce in this area of technologyAinilicates dívision
ãppreciable g"io, ou". p."r"ot opeïâtions are possible' -ny rational
-money
tJbe invested in improved observing facilities
;i-rh" i;", iálent, aotl
for research
over the náxt decade must certainly make atlequate provision
in this Êeld, and for equipping both old antl new telescopes
"nJdr*Iop*"o,
with modern auxiliaries.
Improvement in the performance of a detector or analyzing ilNtrument
and because
has the same efieet as inõreasing the aperture o{ a telescope'
;;; ;il-* oo* b"t t ,eache¡*here tlte optical antl mechanical tshat no peciff-
well understood
telescopes, both radio and optical, are so
"f
""1å".mprovemeit in efficiency seems likely, it is particularly importantto
ør'eat í
il;;";;',h";ffi;l;ocy of the ánalvzing insiruments used at the tend sof thef
is espâcially t*" ú""^.iru the cost of increasing he ize. o
,ãù'rÇ
is enormously greater than -the probable cost of im-
'.fri,
ãlã-iuf"r"op"
"p"rtüt" of photometeis, spectrographs, and direct-plate cam-
;;;rt"c ,Ë "ftlit r"y
;;"r,;;-d rh" ."-" gáin li threshold detection of celestial objects is achiev-
able by either route.
auxil-
Increased efiectiveness of existing telescopes through improved
telescopes' or against
iaries is not, however, an argument against new large
lo*i¿oi"g the design of one larger than any previously built' since any
58
Copyright © National Academy of Sciences. All rights reserved.
OCR for page 66
expansion of the calculatecl horizon of tlese expensive instrumènts \Pill bring
flood of data previously unobserwable by any method. This new infor-
lnì
mation is almost certain to contain revealing surprises'
The general areas of investigation t]]at give promise of a gain in effi-
ciency are:
Rdi,i¿tian Detøctors
The detectors used on optical telescopes are, for the most palt, quanlum
detectors, and the ultimãte ümit of one recorded event for each incident
photon, with negligible spurious background, is an obvious standard against
which to compare current performances.
Photographíc plntes. "lhe highest published value of ùe measureil
of a photographic emulsion is about 1.per cent, but, at
quantum
"ifr"i"o"y
tire very low intensities encountered in astronomical use, the same accumu-
Iated incident energy produces less blackening than under normal testing
condítions (reciproãÇ failute ), anil the eficiency is several times smaller'
in seve¡al observatories have shown by experimenta-
Working
"baking of plates, refrigeration during exposure, anil pre-flashing'
riroo*"t.
tion wiãr
tlat appreciablJimpiovement is possible. What is needecl is a full investiga-
tio' iotà tìe mechairism of recþrocity failure at low intensities, and of possi-
ble increases in the funclamental effióiency of photographic emulsions uniler
of astronomical use. A símilar campaign by the photographic
"onditioo,clirected toward cor¡ections of high-intensiÇ reciprocity- failure
industry,
brought
?" ""*p"ig" inspired by commercial anil military recjirir-ements ), no sig-
hanil, there have been
,p*a g"itt of Zô to tOO times. On the other
,rìff""tri i-ptou"-ents in astronomical emulsions in 15 years'
Photoelecftíc catlndes, Quantum efficiencies of 15 to 25 per cent are
of
commonly realized in the bluà and ultraviolet; the yield falls by an order
magnitude in going to the deep red, and by another faetor of ffve or so in
thÃear-infrarãd. Ã determined search for photoelectricaþ sensitive mate-
rials with higher eficiency in the red and infrared is worth supporting'
Image tubes. The bright prospect held out by the considerably higher
qo"rrt r--"fi"i"ttcy of ùe fhotoelectric cathode relative to the photographic
;l*;;r not be"tt ¡ealizeã after severalhotography have only a few limited
years'efiort' In
been achieved; yet
ipecial cases, results not attaínable by p
59
Copyright © National Academy of Sciences. All rights reserved.
OCR for page 67
I
I
progress has been made. Unless phenomenal improvements in photogÌaphic
of 10 to 20 times is still technologically feasible'
ã-,irioo, ,""Iized, a gain
This very "t"
great prize is worth multiplying the sizable investment already
made several times over.
Infrared iletectors. Excellent detectors of both the photoconductive and
bolometer types are now available. The problems in adapting them to asho-
nomical uses are mainly problems of cryogenic and thermal engineering to
reiluce ambient radiation, and, at the longer wavelengths, ffnding a way of
compensating for variable ihermal radiation from the atmosphere. (See "Sþ
tadiatiotr," p. 61.) The very promising initial efiorts at two or three observa-
tories shoulã be given vigorous continuing support, and entrance of other
techlologically competent groups into this field should be encouraged'
Radío recaioets. As a result of many ímprovements ín radio receivers
for ¡adio telescopes, including the parametric ampliffer and the maser, one
may presently come within a factor of about ûve of the ultimate sensitiviÇ
po.riblr io ground-based radio telescopes. However, such excellent per-
formance is presently available witìr only a few ratlio telescopes' The remain-
ing noise is mainly thermal radiation from components ahead of the receiver,
in-the circuit, and the atrnosphere, ând not noise generateil in tÏe receiver
itself, The support of instrumentation in this ûeld must therefore have two
objectives: If the development of telescopes approaching very closeþ the
dúmate sensitivity perrnitted by the atmosphere and cosmic radio emission;
and 2) the outfitúng of more radio telescopes with the rather complicated
and fairly expensive electronic equipment required to attain low-noise
performance.
Auxiliarg Optícal Ins um.ents
The nartow s¿i¿. In most spectroscopic observations, particularly those
at modeïate and high ilispersion, there is a loss of efficiency because much
of the star image dòes not go through the narrow slit' ,4' large gain in effi-
ciency appears possible through the following developments:
Dí,firøctíon grati.ngs, Theory shows that an increase in the size of the col-
limator is just as efiective as the same proportionate increase in the apelfure
of the telescope. However, clífiraction gratings large enough to hanclle the
60
Copyright © National Academy of Sciences. All rights reserved.
OCR for page 68
9_
l1
l
{
ruling engines
larger colLimator beam are not now available. Development _of
as tJrose now in use
proilucing $atings at least twi'ce as large
*udíb"" t uity profftable investmenl' Increasing the anguìar
""p'"¡f" "ç
tit"lãtl
iä"*" " in higher
àiro"r.ion bv developing gratiigs that maintain their -efficiency
efiective'
ot ¡v g"i"g to the echelle grating, may also be
ãtio"
a large entrance
Inferferometrie spøctron-¿eters, The Fabry-Perot etalon has
resolution' Its
,,"oií. nood luminous efficiency, antl extremely high spectral
il""'å;;il;.;io.-a"tuit"¿ studies of limitetl regions of the spectrum has mov-
in onþ a limited way. The potential of ,Michelson-type
ü"""
in{rareil' is not yet
"-pi"n"¿
iog--in., irrt".terenóe speetrometeis, particularly in the
fuIly explored.
in spectrographs, although
Fast calnpras. The Schmidt camela' as useil
light de-
sivinø excellent definition at low f-ratios, is not well adapted to
larger pieces of appa-
í;;:t, ;,h;;õ".'1" pb"a*i plate, because
^hotog.uphic iut ioo much light. If image tubes
..io
,",* äã""t"¿ block
th"
;;;"-" -h; standard recorders of faint spectra, Jhere-will be aexternal to all
n overwhelm-
;"t ;"d f"." high-resolution camera tlåt has a focal surface
*J u to""t ratio no greater than 10' anil that can be
.h: ;;",t";iil"î,
made in apertures of 12 inches or more'
Atm o spheûc D í stutbanc e s
diameterof
Seeíng.For mosttypes of observations, halving the angular
to doubling the aPerture of the tele-
the seeinidisk of a star is equivalent
;;"p""îåf" ah; empirical iearch for sites with favorable proportions oe f
problem should b
niøhts with good seeing must be continueil, the whole
T:il.,,' ;ñ'";;;sis bviroader and more fundamental investigations' There
seeing, its
Ilr""l¿ t"-" *""h greäter egort at understanding the physics of
\rith height above
,"ilion to terrain alnd meteorological factors, its variation
dome temperatule
aft" n.o"oa, and Þossible improvements from control of
ground cover around the dome' Here
?ì. i".i', riom modiÊåation of
"rä the prizet is great enough to justi{y a considerable investment'
"
again
the final límit
mÅíøtian.The night-sþ brightness (or airglow) sets
SkE
Although there is
to all oiservations with goondlbaseã optical telescopes'
that would
no krown way to eliminat"-ihi' light, ih"t" "'" developments
6l
Copyright © National Academy of Sciences. All rights reserved.
OCR for page 69
reiluce the efiect of va¡iations in ttre brightness that raise the noise level in
photoelectric comparison of stars and adiacent sþ, or introduce fluctuations
into i¡frared meâsu.rements. Similar ¿¡ilÊculties occur in radio astuonomy
measurements at wavelengtls below 3 cm, whe¡e wate¡ vapor in the atrnos-
phere introduces variable opacity. Dual channels, difie¡ential measurementJ,
and t}re choice of a signal-modulation frequency low in noise content are
possible approaches. For the infrared and radio wavelengths, choice of a
site can also make a large dífierence.
The examples cited in the previous paragraphs represent some of the
more persistent obstacles in the way of making telescopes deliver the ulti
mate performance permitted by the laws of optics and radiation. Unpre-
dictable technological developments or new ideas not now foreseen may
alter the prospects considerably in less tÏan a decade, and dictate support
of instrumental developments of an entirely difierent character. The support
given to such projects must be kept flexible and be subiected to periodic
teassessment.
Recom.mendations
I The fraction of the total astronomical research efiort actively de-
l#ft. voted to instrumental development should be increased by a factor of two
in the next few yea¡s. Funds of the orde¡ of $I million a year will be neecled.
2 The support should go to the major observatories and university
astronomy departments, sínce development must be carrieil on close to thé
actual observations anil other processes of astronomy to be kept realistic.
A separate special laboratory for the development of instruments shoukl not
be created, since it would lack this close connectíon.
1flffiì
3 National observatories, such as Kitt Peak, will quite appropriately
builil up a group of astuonomers, engineers, and physicists devoted to instru-
iülifi
mental development and testing. It woukl be a mistake, however, not to have
älffi
I
specialist groups at several observatories or universities attacking various
facets of instrumental problems.
4 In many cases the observatory-connected invesügator will devote
a good part of his primary grant to subconþacts with industrial laborato¡ies.
As an astronomer end-user, who hrows what is needed, he will guide the
work and test the products that come out of it. Examples might be photo-
graphic plates and image tubes. Budgetary support must be adequate to
assure more than desultory attention from the industrial laboratory involveil.
62
i
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AUTOMATION
lnlrodu;tían
The essential continuing requfuement facing us is tTe requirement for more
data. Many problems réquire more observing time on motlerate- and large-
size telescápãs. But every link in the chain of ilata-acquisition must be scru-
tinized to sãe diat a system of the greatest þossible eficiency is used, guaran-
teeing that every tlatum is recoriled and available.
ií th" fittt part of this section we have dealt with auxiliary equipment
used witì telescopes and with the all-important detectors used to turn in-
coming photons into usable data. The remaining link in the data chain,
navini tã do with data-processing and evaluation, also requires substantial
increases in efficiency in the use of time and manpower.
.Astronomy is just emerging into the modern era of automatic control'
The informatión content thai must be processed Ior many astronomical prob-
lems is exceedin gly large, approaching that of high-energy physics' The
techniques fo. uitãmuti" daia-hattdling are in many cases already devel-
op"d; wh"revet and whenever the eficiency and accuracy of acquiring or
p^rocessiog data can be improved, the opportunities shoulil be vigorously
exploitetl.
Only a few optical telescopes âre even partiaþ -automated' either in
their basic operatiãn or for ûnal.ilata-reduction. On the other hand, radio
astronomers ãre already making wide use of modern data-processing tech-
niques, and the revolution is well advanced. Existing radio telescopes are
U"i"g hft"a with modern readout and computer equrpment as râpidly as
fundtg pennits; costs for proposed new radio facilities routinely include
provisiãn for the instrumentation needed for automation' But in opti-
ãul ast onomy a marked increase in the over-all ouþut of fundamental data
is clearþ possible.
Obseivatories embarking on a program lookíng toward the realization
of such obiectives will require the services of engineers experienced in instru-
mentatio; and data-processing; the larger observing centers must think
of persons technicaþ competent in fhis ûeld as a normal part oI their ¡esi-
dent stafis. The drain on the engineering community to provide the rela-
tively small number of engineers required woulil b-e almost negligible, but
the impact on the astronomical community would be enormous' Among
maoy åthe. advantages, the acquisition of such engineers would free the
,j----
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time of astronomers who now do tleir own engineering work, so that they
could procêed with tle primary iob of producing astronomical results.
Acqußition and, Red.uctìnn of Data
fn certain ¿reas of astronomical research the available manpower and
telescope time could be used to produce data much more efficiently if the
burden of data-reductíon were handled by machines rather than by hand.
Programs that could be expedited in this way include: (1) those involving
photographs or records of many stars obiained simultaneously, such as posi-
tions, proper motions, varíable star magnitudes, objective prism speotral
classiûcation, and objective prism radial velocity deteraninations; (2) pro-
grams producing large quantities of simultaneous data on individual objects,
such as multichannel photoelectric photometry, high-dispersion spectro-
scop¡ and spectral scans of bright stars; (3) programs requiring two-dimen-
sional intensity studies or isophotal plots of extended sources, such as
galaxies and gaseous nebulae. An example of the possibilities is furnished
by astrometric-reduction programs. Schemes already proiected and nearing
the stage of initial trial seem almost certain to keep reductions current with
obse¡vation.
There are similar examples in radio astronomy of programs limited by
¡eduction-time requirements: (1) repeated radio scans using multichannel
hydrogen-line receivers to obtain radio isophotes of the distribution of
neutral hydrogen in our galaxy or in neighboring galaxies; (2) analysis of
spectral and temporal characteristics of radio bursts from the sun and
planets; (3) analysis of occultations of radio sources by the moon or by
tfre solar corona.
There is a second class of problems that are limited by available tele-
scope time. ,A,mong these are; (1) direct photographs of very faint obiects,
(2) slit spectroscopic work for ¡adial velocities or spectral classiffcation of
stars, (3) photon-limited single-channel photoelectric photometry or spec-
tral scans, (4) observations requiring excellent seeing or atmospheric trans-
pârency. .A,lthough the most important gain in efficiency will come in the
problems that are reduction-time limited, digitized and automated data-
recording systems can not only improve the reliability antl reduce the tedium
of the observations that are telescope-time-1imited, but also ofier oppor-
tunities for optimum utilization of available quanta and the recovery of
extremely. weak signals otherwise submerged in the background. These
techniques are wèll u¡derstood by the radio observers, and should be more
M
.{- .
Copyright © National Academy of Sciences. All rights reserved.
OCR for page 72
øenerally exploited by optical observers.
"'--,1, ,irita potsibilíty ior improving eficiency comes when the observa-
tlan the setting time of the
tion time peiobject is "o*p".ábl" wíth or less
Then automatic setting of a rapidly moving telescope, a pre-
ì"i.
"oo".^ exposure scheilule, and automatic digital reailout of both posi-
".ã*"*-"¿and -the obsewational ouçut will repay tle cost many times' In
ä*?r ¿"a"
of obse¡vations where the telescope ouþut is an electrical signal
,*"r
;lt
¡" conve¡ted to one (photoelectríc observations, infrared detectors,
ã,
"á"
ã.,ni"o"-typ" image tubes ) , Jirect iligital readout not only reduces human
Uoi"tto pteìenb the information in satisfactory form for rapid reduc-
"rro.. a computeÌ.
-
tion by
Progr"r. iowartl these desirable goals depenils on,support funds for
those obìervatories that are willing anil competent to undertake thé
respon-
present astronomical facilities. Part of the funcls
sibility of automating
wo,ilã go fo, the emplãyment of astronomical instrumentation engineers and
associated technicians.
Deoelopment of Nau Automøtic Instnrlnents
Several of the possibilities for automated insbuments mentioned above
are already verf close to realization, or could be adaptetl -to astronomical
measuremLnts by a slight extension of techniques already krown:
Automatic ttoo-coord'ìtwte mnasuring engi'rc' The astrometlic measur-
ing engine being installed at the Lick Obsewatory will be the ûrst machine
of"this" type. Pìecise æ and y measurements can be -made automatically
fro* pr"-|tog."rttmetl instructions sto¡eil on punched cards' Control by
'"o*jp,rt"t
would be possible. MgaryremenJ of stellar magnihrdes
i"p" o-,
" phúometer is autoÃatically inclucletl, and is reported out along
by' an iris
*ith rhu cãordinate readíngs on punched cards. Variations of the machine
could incluile optional display of the measuring area where an auxiliary
machine for pre-prog.amming was not available or woultl not be efficient'
A slight modhcaiion of the optics would permit conversion of the machine
to a one-dimensíonal spectrum-plate-measuring engine'
Measuríng enghe-mi,crophotomøtar for spøctnnx pløúa-s' Several possi-
bilities, using"prin-ciples tesied separateþ, could be combinecl in an all-
for- spectrum plaies. For, measurement-of the position of
porpot"
"t"[à
ihe'stellar-spectrom lines or còmparison lines, visual displays aiding the
centering of a line proffle relative to a referénce mark are already in use'
bD
Copyright © National Academy of Sciences. All rights reserved.
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ç
with digital readout anil data storage. Automation of tÏe centering process
and pre-programming of a set pattem of lines, as in a radial velociÇ pro-
gram or in the measurement of stellar magnetic ffelds, woulcl be feasible
extensions. Where the intensity clistribution across a spectuum line must
be recorded, as in studies of line proffles or in equivalent width tletermína-
tions for abundance studies, analog computers that allow for ttre calibrated
characteristic curve of the plate are alreaily in use. Transferral of the out-
put from a strip-chart recording to digital form for processing in a computer
can be accelerated by a digitized readout device. The Ênal stage in auto-
mating the entire process is digital storage in a computer or on tape of tàe
information in each spectrum-resolution bit, as has already been done on
hígh-resolution solar spectrograms. The entire process would then become
automatic and iligital, with tle strip-chart serving as a monitor anil refer-
ence, but not as a li¡k in the data-reduction.
Autom.a.tì.callg controll.ed opti,cal telpscopa. As a step on the way to the
automated observatory outlined in a later paragraph, an automated tele-
scope would not only provide a valuable proving ground, but also would
be ext¡emely useful in its owl right. A small instrument could be pro-
grammed to carry out three-color extinction measrrrements on standard
stars, t1rus saving observing time on maior instruments and war:ning of
deterioration of sþ transparency. ,{tmospheric seeing and stella¡ scintilla-
tion could likewise be automatically recorded. A more important program
would involve photoelectric programs on relatively bright stars involving
either the standaril three-color or narrow-band Êlter measurements. This
would be a ¡ealization of the previously cited advantage of speeding up
the routine in cases where the observation time for objects is less than the
setting time.
Infotmnfían Storage
The traditional solution to the need to store enormous volumes of data
regarding the positions, the spectral types, tle magnitudes and colors, tÏe
parallaxes and proper motions, and the binary character of hundreds of
thousands of stars has been the issuance of specialized catalogues. These
.
often become out-of-date before the enormous labo¡ of revised editions
can be completed, requiring recourse to scattered references in tÌìe literature.
The advantages of data-storage on punched cards, witÏ easy editing and
insertion of new information, have already been resorteil to at certain
66
:
,t
rl
,ö
Copyright © National Academy of Sciences. All rights reserved.
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observatories, at least for specialized classes of objects, such as double stars'
While the Panel does not suggest that such methods will replace tÏe use
of the printeil page in conventional libraries as the princþal medium of
storagJand communi"ation, it does urge encourâgement of- central ûles of
machïe-stored data at a few maior observatories that wish to undertake
such projects. Such i¡rformation can easily be printed out when needed,
in digital form, much as is now commonly done with
ú"
"r,il "åo p"""h^nged Information stored in this way, as on punched cards,
computer rogr"rni.
is iåmedåte{ applicable to automatic programming and to theoretical-
anaþsis proiects.
Aut omat e d O b s er o at oú'e s
of automatic conuol systems advances to â state where
AS the technology
more and *or"îf th" operations now under human control can be done
under machine guidance, the time may be foreseen when almost all the
procedures of dãta-acquisition and. äata-reduction useil in observational
out by automatic devices. An entirely autom¿tetl
ästronomy may bu
""oiãd f telescopes, measuring engines, anil otiher ilata-
observatory-a complex o
gathering lrr.t o-"itr, together wìth a complex of plotters, printers, and
ãt¡"r ¿uø display and output devices, all connected to a central computel
and under thelmmediate and direct control of one or more observers-is now
a deûnite possibility. Nearly all tlle work of any observatory falls into one
of the following areas:
Routin¿ obsarcaúdolrs. This area includes the repetitive work of astronomy
thui le"d, to the publication of lengthy catalogue,s and tables' The p-eriod
;f;t;;;;tt"" is tng, and the wori, iedious fõr human beings, should be
handled automatically when possible'
Specìal obsøroafions' Here we ûnd most of the spectacular-work' For these
o'ronr"r.r, onlv a mod.est amount of time (perhaps only a few nights ) may
l" i""4"¿ for the initiat discovery. ,{utomation is a less importart- factor
i" ttto" nttt obselvations, bnt can be valuable in the extensive follow-up
that is invariablY necessary.
Monitorúng obsaraing conditíons. Whenever- possible, small auxiliary tele-
r"ãp"r .f,"'UJ ¡" úseä to monitor the aknosphiric transparency and steatli-
,,"*'r. ih" øeneral skv brightness, antl other quantities of interest' The large
instiumen"ts, relieveã of s=uch tasks, are thereby matle more efiective'
67
Copyright © National Academy of Sciences. All rights reserved.
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DaÍøprocessíng. This area includes all tle operations that are performed
o-nce a telescope provides output. Two types of data-processiig can be
ttrought of: (a) immediate data-display, petmitting tìJobserver-to make
quick_decísions as to ttre best use of telescoie time wã e he is still observing;
(b) the detailed ¡eduction of all the telesóope ouþut..
The automation equipment required for tJre posh_rlated automatic
obseryatory might consist of: (I) a central medium-size digital computer;
(2) an individual control console fo¡ each major instrumenq (B) a;aster
control console from which minor inskuments, ineluding monitors, are
normally controlled; (4) digital readouts for position of each inshument and
digital readouts on all sensors where appropriate; ( 5 ) provision on all instru-
ments for remote conkol of slewing motion, automatic guiding, focusing,
switching of optical components, selecting of detectors, and adjusting ap-
paratus; and (6) automatic measuring engínes for fast and convenient
readout of data, particularþ from photogaphic plates.
The control console for each major instrument would be designed to
permit the observer to control the telescope either directly from the console
or indirectly through the central computer-a fast, core-memory model of
moderate size. The computer occupies tÏe céntual posítion in tlie system
and communicates with tåe consoles anil the telescopes. The digital readout
systems can handle a wiile variety of tasks, including automatic recording of
the position of each instrument. This datum, together with the exact tíme,
deffnes uniquely the position in the sky at which the telescope is poinied,
and eliminates misidentiffcation. Most electrical sensors lend ih"rnr"l.,r"s to
digital readout; photographic plates, because they record such large quan-
tities of ¡l¡t¿,'can be processed eficientþ only witll automatic-measuring
engines of the sort already described.
Recomm.end,atìo¡w
Initial support for tJre design and development of maior instruments for
automation of ast¡onomical facilities should ûrst be given to only a few
experienced astronomical groups with qualiûed stafis. A fully automated
pilot facility jn each category can then be tested, evaluated, and ffnally
made available to other observatories. Such arr approach would help create
standardization and avoid the growth of a hodge-poilge of appioaches.
Already the Kitt Peak National Observatory, with support from thãNational
68
Èl-
Copyright © National Academy of Sciences. All rights reserved.
OCR for page 76
ffi
#
Aeronautics and Space Administration and the National Science Founcla-
)d ffi
tion, is well along io a plan for limited automatic operation of a single
.H
)e
telescope of moderate size. Àstronomers wishing to work in t¡is general area
ñ
(e
should be required to become acquainted with this pioneer facility'
B
Surrreys oÌ existing commercial apparatus inclicate tìat it would cost in
Ë
l¡
tlie neighúorhoott of $Z mlltion to fully automate a moderate-size observa-
g
1C
tory. TËis ffgure applies to an existing observatory-that was not designetl
q
tft
*itÌr automa=tion in mind' New observatories could be automatecl for ap-
ef
! proximately half this amount.
IE
The pioblem that now confronts both optical anil raclio observatories
ril
in the Uiited States is, however, one of updating existing telescopes and
u-
data-analyzing equipment so that they will be partiaþ automatetl antl wíll
-oufrot
iofotmation in a form that can be fetl directþ into
present tieir
P.
ålectronic co-pGrs. Well-conceiveil plans for step-by-step progress toward
nt
this goal should certainly be supported. Typícal examples o{ instrumenta-
tion that will be needed include:
to
rIe
Reaclout, digitizing, and data-processing units to be attached to
1
of
existíng optical t"iescãpes ind plate-anaþsis instluments' These would
fn
cover f,oin^ting coordinaìes, photõmeter settings, photometer ouþut, plate
'ut
pl"t" intensity readings. Digitizations of a single quantity
coordiiates,
of "od i"- tìroosarrâ dollari a complete readout system míght
may cost only u
ìe,
come to $50,000 lor instrumentation.
d,
to
Fully automatic plate-measurement machines with automatic
I
tn-
centering and irovision for pie-programming for sp,ectrum-plates and direct
ng
photogrJphs. hrese -ight ìosi $rso,ooo eich. Pilot models will be more
expensive.
Complete automation of a moderate-size optical telescope, incluil-
3
i.rg pre-prograåmed automatic setting and unattenìled acquisition of ob-
servational data.
[or
Automation of telescope setting, observing loutines, ancl data
4
ew
readout on existing radio telescopes.
:etl
,lly
The Panel has purposely refrai:red from assigning speciffc total dollar
¡te ffeld
values to these categories, since experience in this rapidly developing
,es.
will come from pilo-t installations .tot y"t itt operation Supþort of engi-
nal
Copyright © National Academy of Sciences. All rights reserved.
OCR for page 77
neering and technical personnel needed to initiate anil operate t-hese pro-
grams in individual observatories custitutes part of tle cost. Considera-
tion of the unit costs already known and the adrantages to be gained has
led the Panel to recommend tìat a total of $10 million be allocated to these
pu-ryoses in the next ten years. This is less ttran 5 per cent of ttre ove¡-all
sum ¡ecommendeil in tÏis report; the potential gain in ouþut ís so great tìrat
the engineering of the automation of astronomical observations must be
given high priority in the total efiort.
70
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Copyright © National Academy of Sciences. All rights reserved.
