PoS(ISKAF2010)015

http://pos.sissa.it s the birth of radio ey were initially made by ey were initially made were able to view the Universe in a were able to view the Universe in with lessons learned as we move into the with lessons learned as we move e some of the paths which lead to these of the paths which lead to these e some de the narrow optical window. These early These early de the narrow optical window. th century wa th century astronomy of cosmic phenomena that revolutionized that revolutionized phenomena of cosmic synthesis in , Australia and The synthesis in Cambridge, eative Commons Attribution-NonCommercial-ShareAlike Licence. Licence. Commons Attribution-NonCommercial-ShareAlike eative ected and often unpredicted. Th

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ISKAF2010 Science Meeting - ISKAF2010 - ISKAF2010 Meeting Science ISKAF2010 Assen, the Netherlands June 10–142010 Abstract twentie in events most important the One of R. D. Ekers ATNF - Science Space and Astronomy CSIRO Australia Sydney, NSW, E-mail: Golden Age of of Radio Astronomy Golden Age ever astronomers For the first time astronomy. spectrum outsi region of the electromagnetic discoveries were usually unexp "". unconventional who built very from other disciplines scientists individual of aperture This included the development Netherlands. a plethora These early pioneers discovered I will explor our knowledge of the Universe. and conclude discoveries in radio astronomy next "Golden Age".

PoS(ISKAF2010)015 telescopes is now radio astronomy provides a astronomy radio telescopes with many exciting results exciting results with many telescopes ts and discoveries including three ts and discoveries d of astronomical research using radio research using radio d of astronomical ion and large optical ents across all radio frequencies. ents across all radio frequencies. tions at many new wave length bands tions at many ing as a source of radio interference!” ve rejuvenated radio astronomy in many in many ve rejuvenated radio astronomy An unexpected source of noise (’s ory to further pin down the location in r father said his boss made him change him r father said his boss made ergence of this new branch of astronomy. ergence of this new branch of astronomy. was “of extraterrestrial origin,” there was was “of extraterrestrial origin,”

errestrial origins. Reaction from Bell Labs onomical community at the time and Jansky and Jansky at the time community onomical 2 discovery was appreciated. Jansky’s daughter e source of interference to trans-Atlantic to trans-Atlantic e source of interference ve new history of early rl Jansky, working at the Bell Telephone Laboratory, rl Jansky, working at the Bell Telephone radio techniques. innovation is occurring. -ray) are made possible by the space observatories. The The possible by the space observatories. are made -ray) γ Ekers Jansky, and later Reber, opened a new fiel Jansky, and later waves. developmen instrumental Many innovative discoveries. winning the new radio are using Many astronomers but little instrumental is eclipsed as observa Radio astronomy (IR, UV, X-ray, of new optical instrumentat development progressing faster than ha The SKA and its various pathfinders countries with new innovative developm The beginning - first : 1930s The beginning - The heroic golden age: 1950s - 1960s The heroic golden 1970s - 1980s golden age: The decadent The decline: 1990 - 2000 The new golden age: 2010….. definiti [1] Woody Sullivan's

• • • • • “emission from interstellar space” to “emission apparently from interstellar space”. space”. interstellar apparently from to “emission space” interstellar from “emission – Moreau Jansky-Parsons remembered that he – Moreau Jansky-Parsons remembered Once he had determined that the interference that the interference determined Once he had Laborat the Bell Telephone little support from astr space. It was also not accepted by the died in 1950 before the importance of his was underwhelming: “so faint not even interest was underwhelming: 2.1 Karl Jansky's discovery In the course of trying to identify th comprehensive and insightful study of the em and insightful comprehensive telephone communications Ka in 1933 [2]. radio emission discovered cosmic earlier each day 4 min arrived the peak signal each day but Hiss) was peaking Cosmic have extrat and Jansky realised that it must 1. The Ages of radio astronomy astronomy Ages of radio The 1. Golden Age - ISKAF2010 Age Golden 2. Beginning of radio astronomy PoS(ISKAF2010)015 ittle interest so longer wavelengths. origin of the solar origin one should follow up. one should follow stars? Note that at this both galaxies, far outside our hedge on the extragalactic origin of radio emission from the centre of the from radio emission of astronomers showed l astronomers showed with intensity varying on time scales with intensity varying on time star that the Chinese had seen explode the Chinese star that the strongest of the mysterious discrete the strongest of the mysterious lescope was constructed on the cliff to built to to locate the built to to locate the in Wheaton, Illinois and started looking and started Illinois in Wheaton, ars [7]. The idea of a cliff interferometer ars [7]. The idea of a cliff interferometer interesting that some and making a radio map of the Galaxy of a radio map and making t explosion that they were among the t explosion that they were among sky but had great difficulty getting it sky but had great difficulty getting

greater surprise. Centaurus A and Virgo A greater surprise. Centaurus A MHz but finally at 160 MHz he eventually MHz but finally at 160 MHz he d make it stronger at shorter wavelengths it stronger d make galactic emission to cosmic rays. to cosmic galactic emission waves and those reflected by the sea (a ng graduate specializing in electronics and ng graduate specializing 3 the non-thermal emission was an unexpected emission the non-thermal by Jansky but stronger at l but there was no concept of non-thermal l but there was no concept of non-thermal s not until 1950 that the synchrotron radiation s not until 1950 that the synchrotron they had conspicuous bright optical But what was it? There was no optical But what was it? There concluded that the source must be small be small concluded that the source must horter wavelengths than Jansky since the horter wavelengths thought to be radio stars. es - not stars! They were es - not stars! They actic plane was made of such This discovery, with some help from the now very help from This discovery, with some e radio sky. Bolton et al had to Ekers One was the Crab nebula, the remnant of a One was the Crab nebula, the remnant In 1946 at Dover Heights near Sydney a te In 1946 at Dover made the first radio map of the first radio map Grote Reber made emission In 1946 Hey found a source of radio In 1937 Reber built his 32’ parabolic dish parabolic his 32’ In 1937 Reber built In 1933 Karl Jansky had reported the discovery Karl Jansky had In 1933 time there was no theory linking the diffuse there was no theory time the interference between the direct measure to [6] and identify the radio st radio emission to and which was used radar seen in ship-borne interference multiple path from came measure it to Bolton and his colleges were able to use information. positional improve three of to identify accurately enough positions were which sources of radio emission diameter. This was the first “radio star”. “radio This was the first diameter. the whole gal counterpart. Was was This cliff interferometer mirror). Lloyd's 2.5 Cliff interferometer for radio emission. First he looked at s First he looked for radio emission. woul emission radio thermal predictions for or 900 [3]. Nothing was seen at 3300 MHz to that seen static similar cosmic detected had to be non-therma This radio emission It wa at the time. emission astronomical [4]. was understood mechanism observations published. Confirming Jansky's of was not serendipitous but the discovery discovery. [5]. He correctly of seconds to minutes 900 years ago. The other two were an even were discrete sources like Cygnus A but identifications which were galaxi such a violen way but undergoing own milky 2.4 Cygnus A, strongest radio source in the sky brightest objects in th 2.3 The ascendance frequency radio of low astronomy the Galaxy. Grote Reber thought this was so the Galaxy. Grote built a dish." and myself I consulted with to get the paper published. to the eventual in the US, lead Palomar at Mt astronomers enthusiastic optical Golden Age - ISKAF2010 Age Golden Rebers'2.2 Grote challenge communication, he later commented: "Professional communication, At the time he was a 22 year old engineeri he was a 22 year old At the time PoS(ISKAF2010)015 spectral line due to ous that these new ous that on - a US discovery ations showed that ations showed that synthesise an image of synthesise an image bout its detectability. These stories bout its detectability. These stories existence of a radio These were followed by a brief note in These were followed by a brief r, this technique was impractical with a r, this technique was impractical a radio source survey of the North Pole n with the new generation of telescopes. with moveable elements were made at the were made elements with moveable t reaches of the universe. A new field of A new field of of the universe. t reaches rnational collaborati y, radio galaxies could be observed from could be observed from y, radio galaxies the best optical telescopes of the time. of the time. the best optical telescopes array of small dishes in Australia. dishes in Australia. array of small

e groups currently searching for the same the same e groups currently searching for Cambridge surveys led to surveys led Martin Cambridge splay used EDSACII which was the first use 10]. It & Purcell at was detected by Ewen although later observ r imaging solar bursts which were strongly solar bursts which were r imaging y corrupted by confusion and the analysis y corrupted by confusion The American and Dutch results were The American 4 first observations using a range of Fourier rst demonstrated the earth rotation synthesis e in Cambridge, UK, e Cavendish Laboratory in Cambridge, at it was immediately obvi at it was ourier components was made by McCready, was made ourier components that it would be possible to initial scepticism a Nature [11] [12]. of all the radio sources, Cygnus A. It was found to be a A. It was radio sources, Cygnus of all the radio astronomy imaging. Comparable images at low images Comparable imaging. radio astronomy Ekers The first published suggestion should give impetus and some lessons for th some and should give impetus the epoch of re-ionisation. line from synthesis Aperture 3. the spin flip transition of neutral hydrogen [ the spin flip transition of neutral involved inte Harvard in1950. The discovery Australian groups. by Dutch & confirmed issue of published in the same had also Christiansen and Hindman that Pawsey mentioning issue from the same the line in Australia. detected and the period difficult war time the which discusses in-depth commentary an for Chapter 16 [1] See Sullivan's Cavendish Laboratory [14] [15] [16]. Cavendish Laboratory 3.2 Earth rotation synthesis images at th In June 1961 radio astronomers 3.1 The beginnings of a range of F the radio sky by measuring Pawsey and Payne-Scott in 1946 [13]. Howeve suitable fo and was not cliff interferometer, and frequency. The variable in both time with an interferometer measured components used 4C aerials operating at 178 MHz to make and graphical di region [17]. Computations astronomy was born. was astronomy luminosit As a result of their tremendous the possible In 1945 van de Hulst predicted for of a digital computer agai frequencies are only just now being made 2.6 21cm 21cm 2.6 very faint galaxy so incredibly distant th galaxy so incredibly very faint distan the most were probing radio telescopes far beyond the reach of very great distances, counts based on early Radio source number data were badl Cambridge even though the This was 7 years after Christiansen [18] fi with an observation of the quiet using an Golden Age - ISKAF2010 Age Golden of the strongest identification argue in favour of an evolving universe [8], argue in favour of was Universe - the conclusions were right Ryle's [9], incorrect was mathematically evolving. PoS(ISKAF2010)015

erating at 21cm with erating at 21cm e the Fourier transforms by transforms e the Fourier CD. Key radio engineers from round the round the from CD. Key radio engineers ecome a purely Dutch affair. The design ecome . It was very ambitious with 100 x 30m . It was very ambitious with 100 e Nobel Prize in 1974 "For his observations and observations his "For e Nobel Prize in 1974 rt at an OECD Symposium in 1961. The rt at an OECD Symposium

om CSIRO in Sydney. The Benelux Cross om tion to avoid confusion. The science goals tion to avoid confusion. The science therlands – Belgium project initiated by initiated project therlands – Belgium ce of Jan Hogbom, a recent PhD graduate PhD a recent ce of Jan Hogbom, 5 acing information. Op acing information. astronomy source counts for cosmology. source counts for cosmology. astronomy ed impractical at the time. at the time. ed impractical took many months to calculat took many through an agreement with the OEEC (Organisation for for the OEEC (Organisation with an agreement through Ekers Artists impression of the Benelux Cross (Ben Hooghout 1963) of the Benelux Cross (Ben Hooghout Artists impression 3.4 Westerbork: 1970 1970 Westerbork: 3.4 under the influen was drastically modified Cambridge,from and Chris Christiansen, fr Figure 1. Figure By 1964 the Benelux Cross project had b baselines to 1.5km to have sufficient resolu baselines to 1.5km by Oo for the Benelux Cross were described the early to study power resolving and enough sensitivity goal was to have primary universe through source counts. Professor to use the radio Professor Jan Oort was International coordination now the OE Cooperation), European Economic Cross [20] was a joint Ne The Benelux hand so the method was consider the method hand so Ryle Martin in 1971. was awarded th the 5km and One-Mile Telescope in 1962 the [19] build went on to group The Cambridge synthesis particular for the aperture technique". in inventions, Benelux Cross: 1958 3.3 telescope the world were brought in to design dish to add short sp dishes plus one 70m Golden Age - ISKAF2010 Age Golden group the Australian However, PoS(ISKAF2010)015

. able fraction of all

e role of Big Science y source distributions. y source distributions. provided a number of provided a number spacings were the key to spacings were the

arch group involved. Five of

Victor Franz Hess (shared) Chandrasekhar Subrahmanyan Alfred Fowler William John C. Mather, George F. Smoot Sir Martin Ryle Sir Martin Arno A. Penzias, Robert W. Wilson Russell A. Hulse, Joseph H. Taylor, Jr. Davis, Jr., Masatoshi Raymond Koshiba which have resulted in Nobel Prizes. which have resulted

against the discovery date and a subjective subjective a date and against the discovery from Figure 2 that th extended to arbitrar

dio wavelengths, a remark 6

ing moveable elements and earth rotation and earth rotation elements ing moveable qual spacings. This qual spacings. This

ynthesis (WSRT) which which Telescope (WSRT) Radio ynthesis

eases in importance with time [21] time with eases in importance , spacings and these redundant , spacings and these

e of the instrument or rese e of the instrument

array concepts. The WSRT has 14 x 25m dishes. Four has 14 x 25m The WSRT array concepts. Ekers Nobel Prizes for astronomy Nobel Prizes : 1962,70 Cosmic X-rays 1962,70 Cosmic 1989 CMB 1950 Chemical Elements Radiation Neutrinos 1950 Chemical 1974-78 Gravitational 1987 Cosmic 1912 Cosmic Rays Synthesis 1912 Cosmic Evolution 1960 Aperture 1967 1965 CMB 1931 Stellar Table1

Table 1 lists the 10 astronomical discoveries 10 astronomical Table 1 lists the

2002 2006 1983 1993 2002 Prize Experiment Subject Experiment Prize 1936 1974 1974 1978 1983 Laureates In Figure 2 I have plotted these discoveries In Figure 2 I have combined aspects of aperture synthesis us aperture synthesis aspects of combined with the grating synthesis other ten are at fixed e moveables and the discoveries 4. Nobel Prize scal the relative indication of at ra these ten discoveries have been made Golden Age - ISKAF2010 Age Golden S Westerbork into the was transformed identical, and hence redundant identical, and hence self-calibration could be the realisation that quite clear Nobel Prizes in astronomy. It is discoveries incr facilities in making PoS(ISKAF2010)015

tary scintillation. communication [23]. discovery with an indication of the an indication of discovery with yn Bell made a serendipitous discovery yn Bell made e discovery of the Big Bang radiation. wish "For his decisive role in the wish "For his decisive role in the ying to understand the apparent losses in e Taylor and Russell Hulse for the e built to study interplane

itational radiation [24]. This is a classic This is a classic [24]. radiation itational ans-Atlantic telephone ans-Atlantic 7 based on his prediction was already in Bell Laboratories where Jansky had discovered of a predicted phenomenon. Bob Dicke’s of a predicted phenomenon. hod of prediction and observation. Ekers e experiment [21] e experiment Nobel Prizes in astronomy vs. date of Nobel Prizes in astronomy verification of Einstein's prediction of grav verification of Einstein's of the scientific met example The 1993 Noble Prize was awarded to Jo 4.3 Gravitational radiation: 1974 radiation: Gravitational 4.3 4.2 Cosmic microwave background: 1965 in the same thirty years later, Some and his student Jocel In 1967 Tony Hewish discovered the three degree Arno Penzias and Bob Wilson radio emission, cosmic background (CMB) while tr microwave cosmic a radio antenna also designed to support tr They were awarded the 1978 Nobel Prize for th This was a serendipitous observation to search for CMB radiation experiment progress. 4.1 discovery Cambridge: 1967 Pulsar discovery Cambridge: 4.1 of pulsars [22] at Cambridge with a telescop of pulsars [22] at Cambridge The 1974 Nobel Prize was awarded to Tony He The 1974 Nobel Prize was awarded pulsars". discovery of Golden Age - ISKAF2010 Age Golden relative scale of th Figure 2: PoS(ISKAF2010)015

. It is clear that has declined with with has declined e big general purpose

bulation of the key bulation of the key blackbody form [25] and blackbody form than build special purpose (b) Predicted v Serendipity general user facilities cellent examples of discoveries made of discoveries made cellent examples the sensitivity of th awarded jointly to John C. Mather, NASA Mather, NASA jointly to John C. awarded was submitted to the US National Science US National Science to the was submitted

[27] included a ta [27] included a ginning of the field in 1933 to 2000. Figure ginning of the field special purpose instruments has declined special purpose instruments al purpose instruments al purpose instruments 8 eir discovery of the eir discovery of dio Astronomy from [27] from Astronomy dio purpose instruments leave the field. purpose instruments crowave background radiation". crowave background against time, comparing the discoveries made with special with special made comparing the discoveries time, against ng general purpose instruments ng general purpose instruments Ekers Key Discoveries in Ra Figure 3: (a) Type of instrument (a) Type of instrument

instruments have already all been made. have already all been made. instruments Mexico New VLA 6. of possible reasons: as discussed by Harwit [28]. There are a number with time with discoveries made of The number to use existi - It is easier ones. - The people who can build special without - The discoveries which can be made 6.1 Building the VLA 6.1 Building the the VLA In 1965 a proposal to construct Foundation (NSF). The VLA construction commenced in 1972 and it was formally formally in 1972 and it was Foundation (NSF). The VLA construction commenced 3 (a) plots these discoveries on the larger those made with purpose instruments University MD, USA, and George Center, Greenbelt, F. Smoot, Goddard Space Flight Prize in Physics for 2006 was The Nobel CA, USA, "forof California, Berkeley, th mi the cosmic anisotropy [26] of Astronomy Discoveries in Radio 5. Other et al unknown. Wilkinson by exploring the provides ex beginning of radio astronomy The since the be astronomy discoveries in radio with speci of discoveries made the number Golden Age - ISKAF2010 Age Golden - the microwave 4.4 COBE background: 1989 time. Figure 3 (b) shows that serendipitous discoveries are more prevalent at the prevalent are more discoveries that serendipitous Figure 3 (b) shows time. inception of a new branch of science. PoS(ISKAF2010)015 4 Time (%) Time (%) on in other areas of e during its initial ement to the progress ement

st never what it is known for. Almost st is known for. Almost never what it listed the key scientific drivers (8 pages) pages) key (8 drivers listed the scientific ogy. science which may It also listed other re, and the WSRT to do weak source counts. weak source counts. to do WSRT and the re, which is one of the most productive which is one of the most son et al [27] were not, often could not have son et al not, often could not have were [27] y a quarter of its tim de astronomy. It had already been well de astronomy. discoveries in astronomy result from from result discoveries in astronomy ility. Instruments used for discoveries are ility. Instruments scopes. Bank was built to For example, Jodrell also showed that the normal mode of also showed that the normal

science being done with the VLA between science being done with the VLA Cosmology Topic Observing Topic Observing conclusion that most scientific advances e most productive ground based telescope based telescope productive ground e most soon after new technology appears, and 9 follow technical innovati lied quantitative measur 9 Galactic Centre 9 Galactic etc 3 5 X-ray, 1 13 Molecules 3 Time (%) Time (%) of VLA Science 1980 - 1991 blications and citations. citations. and blications Ekers is exponential. is exponential.

What a radio telescope What a radio telescope was built for is almo Harwit [28] showed that most important The author compiled a list of the actual The author compiled Items inItems boldwerekey the science drivers the in 1967 fundingproposal Supernovae 4 Astrometry Astrometry 1 Star formation Solar system AGN 4 Supernovae 9 6 VLBI Pulsars 3 2 Stars 16 Interstellar medium 4 medium Interstellar Stars 16 Galaxies 14 Radio Galaxies Topic Observing Topic Observing technical innovation. The discoveries peak technical innovation. The the technical capab usually within 5 years of are more phenomena astronomical new He also noted that the observer. built by often by researchers trained outsi frequently found science. In 1960 de Solla Price [29] app the and reached of science (scientometrics) His analysis follow laboratory experiments.

established that most scientific advances established that most growth of science 7. Exponential growth in science 7. Exponential growth 1980 and 1991. Table 2 shows that the VLA, 1980 and 1991. Table 2 shows that spent onl of all time, telescopes astronomical and this included: radio galaxies, quasars, cosmol galaxies, radio and this included: ever built, in both its pu ever built, 6.2 VLA science Table 1 of discoveries in invariably, the Wilkin ionosphe trails, Arecibo the study study to meteor submitted to NSF Proposal funding The 1967 VLA Hydrogen studies,benefit: planets, galactic line. and 21cm proposal. listed in the funding key science drivers decade of operation on the Table 2. Distribution Golden Age - ISKAF2010 Age Golden th VLA has been in 1980. The inaugurated been, in the minds of the designers of these tele designers of of the minds the been, in PoS(ISKAF2010)015 also recognized the l processing at high ng the ceiling on cost ng the ceiling ears. Also in this case ears. Also in this . Do we have such new searcher to Institute to ch step removing a resource ch step removing : Radio Telescope Sensitivity vs. time. itely without hitti ting and die out [21] [29] [30]. On the [30]. [29] [21] ting and die out ience' and 'big science' to describe the to describe and 'big science' ience' Solla Price [29] [30] ed a ceiling the rates of new discoveries the rates ed a ceiling acity to apply digita Figure 4 Pointsrelative continuum are the sensitivity when thewere built, telescopes upgrades.or after major VLA*EVLA upgrade. is the proposed SKA is the sensitivity for a telescope which has not yet been built. iously conceivable. Finally, the move to iously conceivable. Finally, the move tion from huge single dishes to arrays of huge single tion from in 1940. It has been exponential with an in 1940. It has been

ely provides one of the keys for change. opes used for radio astronomy since the for radio astronomy opes used 10 ed SKA will also be needed to avoid the be needed to avoid ed SKA will also scussed in the previous section, sometimes scussed in the previous section, sometimes their large scale integration into complex into complex scale integration their large

improvement? In radioastronomy the improvement? hnology or find new ways to organize our hnology or find new ways to organize technologies reaching ceilings and new new ceilings and reaching technologies e in sensitivity can continue to International Facility, ea since 1940, doubling every three y since 1940, doubling science: 5 e transition from Individual Re e transition from big Ekers science to little Exponential growth cannot continue indefin Exponential growth cannot If the improvement in sensitivity has reach has in sensitivity If the improvement Figure 4 plots the sensitivity of telesc plots the sensitivity Figure 4 growth? 7.2 How to maintain exponential National Facility and, finally, sc 'little the terms ceiling. He coined limitation two extremes. 7.3 From From 7.3 will decline and the field will become uninteres will become and the field will decline resources the exponential increas technology to continue the exponential and of transistor amplifiers combination and formation beam adaptive such as multiple processes bandwidth thereby realizing interference rejection in ways not prev active as the propos such facilities international resource ceiling. di or available resources to continue. As to the rescue but de technical innovation comes role played by th important discovery of extra-terrestrial radio emission extra-terrestrial discovery of tec other hand, if we can shift to new which can be duplicated inexpensiv systems increase in sensitivity of 10 increase in sensitivity telescope radio we can see particular The other key technology is the computing cap Golden Age - ISKAF2010 Age Golden of radio telescopes7.1 Growth technologies being introduced e.g., the transi technologies being dishes in the 1980s. smaller PoS(ISKAF2010)015 argued that it is e facilities make it make e facilities r management, and lack of and lack r management, on a scale which no single institute can on a scale which easing big science component, this doesn't doesn't this component, easing big science e main role of a key science driver is to e main ectric, (Nobel Prize for Chemistry, 1932) 1932) ectric, (Nobel Prize for Chemistry, the major purchases can be made late in made purchases can be major the research on a scale can nation no single which research on a scaleresearch can which no individual nd as discussed it in the following sections, is ere is no Moore’s Law escalator to help the field. He also

ence? ence? Large scal key science drivers carefully and not allow He argued that you need to encourage He argued that you need to encourage ent early; the SKA will inevitably be the ent early; the SKA will inevitably 11 oup, or even nation can afford. Large scale oup, or even nation can afford. Large ries but you can plan a work environment ries but you can plan a work environment the design to follow up on the unexpected up on the unexpected the design to follow est changes in technology by designing the done and to quantify specifications. e opportunities for discussion in an open e opportunities for discussion in protection of information, ove Ekers

afford. afford. afford. International Facilities are International built to enable Institutional Facilities are Institutional built to enable National Facilities are built to enable research While the progression clearlyan incr While the progression involves

What can we learn from our past experi What can we learn from our past We need to maximise flexibility in need to maximise We In the 1950s Irving Langmuir, General El In the 1950s Irving Langmuir, General • • • mean the small science role has to disappear, a important that it doesn't disappear. that it doesn't important necessary to avoid the over to pursue other ideas. time 9. Lessons learned single gr possible to do projects which no be very the unexpected discoveries but we must also be able to make facilities may aware of the pitfalls. which increases the chance of discovery. which increases the chance of discovery. to explore, provid individual freedom and encourage contacts outside environment the known science that can be promote use the same or spectral bands which beams multiple such as simultaneous components, expensive of reuse the multiple for cost we must seek ways To reduce the collection areas. We need to exploit the areas of fast developm Begin the software the project. largest software project in astronomy, and th cover software costs. noted that you can't plan to make discove to make plan noted that you can't use that we must discoveries. This means that th to constrain the design. Remember them in such a way that signal processing hardware 9.1 What does this mean for the SKA? 8. Managing scientific research Golden Age - ISKAF2010 Age Golden PoS(ISKAF2010)015 they will answer issues but they must be issues but they must nnovation. We need a user nnovation. We in forefront facilities and to keep the in forefront facilities and to keep tive. Representative committees are tive. Representative committees fell away as resources were directed to to were directed away as resources fell astronomers at many levels so it is at many astronomers providing the interface to the general providing the interface to the general not the old questions e knowledge pool available. We also available. We e knowledge pool risk averse. I have always thought it risk averse. I have always thought standard projects. These may be high standard projects. These may t processes do not naturally do this. t processes do not naturally do this. We need to learn how to collaborate in We

ovative instrumentalists and programmers and programmers ovative instrumentalists with the user community right by accessing right by accessing with the user community ich technology development in many of the of the many in development ich technology 12 tive research groups and technology tive research groups and technology rector, not to make decisions. rector, not to make cilities and we should understand why d engineers who understand how to build will drive our new endeavours. new endeavours. our drive will explore technical and scientific technical and explore eers engaged in the project. in the project. eers engaged hout extinguishing individual i should act as a warning. should act as a warning. Ekers best scientists and engin in the community. development also seed future innovation. group but they may risk and benefit only a small with expert users The priesthood model be effective. may community astronomy

the diversity of ideas and broadening th the diversity of ideas happy and produc keep them to important and needed but tend to be conservative better for a TAC to advise the di need the support from the community of the community from need the support but current citation based advancemen You need to reward and keep the inn You need to reward and keep the innova to maintain It is important non- A process is needed to support the How to provide rapid response to unexpected events. Continued investment is needed to mainta is Continued investment It is important to get the interaction the interaction to get It is important

• • • • • • 9.3 How do we go forward? How do we go forward? 9.3 build new large scale fa We must governments fund large scale infrastructure. fund governments international facilities wit but we also cases science specific for predictions to test community to set specifications scientists an need big picture system since their innovation instruments will raise. but the new questions they is of these new instruments The excitement 9.2 Challenges for large scale facilities 9.2 Challenges for traditional university departments systematically departments university traditional the national facilities, instrument. the final to optimise able to adapt to change to Pathfinders are necessary Golden Age - ISKAF2010 Age Golden wh during the past two decades USA over in the The experience in community. expertise the technical maintain must We PoS(ISKAF2010)015 , Proc. , Nature , Nature , Nature , Reidel , Nature , MNRAS , MNRAS in , Nature 157, , Nature , Aust J Phys, Vol 8, Phys, , Aust J , Proc. I.R.E., 21, , Nature 168, p356,1951. 168,, Nature , 1987, Reidel, p545. , MNRAS 120, p220, 1960. Classics in Radioastronomy on with a 4.5 minute of arc pencil- , Phys Rev 78, p616, 1950. , Nederlandsch Tijdschrift v. Natuurkunde 11, Positions of Three Discrete Sources of Galactic Galactic of Sources Discrete Three of Positions

Solar radiation at radio frequencies and its relation relation its and frequencies radio at radiation Solar Radio-Frequency energy from the sun the from energy Radio-Frequency 13 Radio Source Counts and their Interpretation Interpretation their and Counts Source Radio The Spatial Distribution and the Nature of Radio Stars Radio of Nature the and Distribution Spatial The gs of the IAU Symposium No. 124 Symposium of the IAU gs Fluctuations in cosmic radiation at radio frequencies radio at radiation cosmic in Fluctuations The distribution of radio brightness over the solar disk at a at disk solar the over brightness of radio distribution The ation availableW Sullivan, in Nature, 164,101. , Cambridge University Press, 2009. Press, University Cambridge , Radiation from galactic hydrogen at 1420 Mc/s 1420 at hydrogen galactic from Radiation Cosmic radia tion and radio stars radio and tion radia Cosmic The interstellar hydrogen lineand 1420an at of Mc/s estimate the galactic , Proc IRE 28, p68-70, 1940. A radio survey of the North Polar regi Polar North of the survey radio A The synthesis of large radio telescopes synthesis The Ekers , Radiogolven uit het wereldruim het uit , Radiogolven Electrical Disturbances Apparently of Extraterrestrial Origin Extraterrestrial of Apparently Disturbances Electrical Cosmic Noise The distribution of radiation across the solar disk at metre wave-lengths metre at disk solar across the of radiation The distribution Distribution of radiation from the undisturbed sun at a wave-length of 60cm of wave-length a at sun undisturbed the from radiation of Distribution Distribution of radiation across the solar disk at a frequency of 81.5 Mc/s 81.5 of a frequency at disk solar the across radiation of Distribution , MNRAS 125, p39, 1962. Proc Roy Soc A190, p357-375, 1947. 1947. p357-375, A190, Soc Roy Proc Cosmic Static Cosmic , Naturep357-358, 168, 1951. H.M. Stanier, Stanier, H.M. 165, p354-355, (1950) (1950) p354-355, 165, Ryle, M.; Hewish, A., Ryle, M.; Hewish, 113, p597-612(1953) M. Ryle, A.C.Neville, system beam Warburton, J. W. Christiansen, p474-486, 1955. K.E. Machin, Machin, K.E. P.A. O’Brien, observations two-dimensional - sun quiet The III centimetres. 21 of wavelength L.L. McCready, J.L. Pawsey, R. Payne-Scott, R. Payne-Scott, Pawsey, J.L. L.L. McCready, H.I. Ewen, E.M. Purcell, E.M. Ewen, H.I. Oort, J.H. C.A. Muller, rotation H.C. Van de Hulst H.C. Van p210-221,1945. English transl 1982 spots, to sun 167, p889-89,1951. Observational cosmology; Proceedin cosmology; Observational K. I. Kellermann and J. V. Wall, 1987, Wall, V. J. 1987, and K. I. Kellermann J.S. Hey, S,J. Parsons,S,J. J.W. Phillips,Hey, J.S. A230,Roy 448. Soc. M. Ryle, and P. A. G. Scheuer, 1955, 1955, Scheuer, G. A. P. and Ryle, M. 387. 387. Herlofson, N. H. Alvén, 158,1946. p234, McCready, L. R. Payne-Scott, Pawsey, J. L. p158-9, 1946. Stanley,O. andG. J. Slee, 1949, B. J. G. Bolton, Radiation, Radio-Frequency W.T. Sullivan, K. Jansky, 1933, G. Reber, G. Reber,

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