A Wide-Field 8 meter Telescope
for Canadians

A Proposal to the
Long Range Planning Panel
March 9, 1999

An 8 metre telecsope almosts fits in the CFHT dome



Executive Summary

The astronomical community must launch the immediate refurbishment of the Canada-France-Hawaii 3.6 meter Telescope as a wide-field, 8 meter aperture, high spatial resolution telescope that takes advantage of recent technical advances. The climate which inspired the LRPP process has at last brought this long hoped-for project within reach. This unique facility stands on its own but is also a crucial prerequisite to our future capabilities at the frontiers of astronomical research. Among the principal science problems to be tackled by a wide-field 8 meter telescope there are:

The combination of wide field (nominally 0.7 degree 0.7 degree) and superb image quality (0.35 arcsec FWHM) gives unprecedented scope for deep, large scale imaging and spectroscopic investigations, both in the visible and near-infrared. With a collecting area that of CFHT (and an image sharpness 1.4 better on average), this telescope will reach objects 3 times fainter than CFHT in the same observing time and will be 10 times faster for the same objects. The wide field of this telescope leads to far more resolution elements than other 8 meter telescopes, allowing the sky to be searched enormously more effectively, and enabling major new programs. In order to keep Canadians competitive, and to enable optimum use of our partnerships in NGST and LMA, fast deployment of the new telescope is considered to be of the utmost importance. We urge a full commitment before the end of 2000, and our goal is to achieve scientific observing by early 2005. With careful planning, it will be possible to achieve engineering first light within 12 months of the decommissioning of CFHT.

The total capital cost of the telescope is estimated to be C$128M (including a first complement of instruments). It is defensible on the basis of science and scientific excellence to aspire to complete ownership of the proposed telescope. However, our pragmatic goal is an international partnership in which we have a 40% share. A minimum of 25% is essential, but has accordingly reduced practical benefits and more significantly reduced strategic benefits. Most of the operating costs for a 40% share are already present in the CFHT budget, although a modest increase may be needed.

The advantages of replacing the current CFH 3.6-m telescope with an 8m are many. We maximally exploit what is acknowledged as one of the best sites in the world. The telescope can be built quickly and at cost savings by cloning an existing telescope design (VLT or Gemini). We continue to make use of the current superstructure (pier, coudé and building). The administrative infrastructure of CFHT is already in place.

The telescope will possess a small but powerful and complementary suite of instruments which will effectively be in constant use. The CFHT Megacam optical imager is perfectly matched to the imaging field and image quality that we plan for this telescope. A wide field infrared imager will be a key instrument for studies of star forming regions and distant galaxies. A wide-field multi-object spectrograph will provide the spectroscopic complement to the superb imaging qualities of the telescope and will follow the imaging instruments to maximize the scientific impact. The existing coudé will open new observational windows on nearby stars and distant gas clouds.

Renewing the CFHT as a wide field, 8m aperture will present unique capabilities and extraordinary scientific opportunities to Canadian astronomers. This will provide strategically crucial complementarity to the powerful narrow-field Gemini telescopes. The new telescope will also augment the 13.2% share of observing time Canadian astronomers have on each of the two Gemini telescopes. The wide field 8 meter telescope can (and should) be be reality on a short timescale. It is important to seek partners and commit to this telescope immediately. We urge that a working group be established immediately with the aim of preparing this project for implementation with full funding in about a year.

A Scientific Opportunity for Canadians

What happened during the first half of the universe's evolution? How does large scale structure evolve over time? How are galaxies like our own created? How do stars form within them? Do those stars have planets? How does the pattern of galaxy clustering grow in our expanding universe? Canadians have begun ground breaking work on these questions but need new facilities. Here we focus on the best available current option, which is a wide-field 8m class telescope. This telescope will be able to help us answer the following questions.

All these questions need the largest possible ``aperture-pixel'' product for practical investigations. That is, the telescope should be as large as possible with as many resolution elements in the focal plane as possible. The number of pixels increases with field size and image sharpness. Specific ``design reference programs'' to answer these questions are presented in the Appendix. They concentrate on the pioneering work to be done in the infrared and with complimentary information from the visible part of the spectrum. The science programs in the Appendix are examples and do not completely cover the opportunities, some of which are yet to be discovered!

Studies with 4 meter class telescopes over the last 30 years have discovered much about the universe around us. Furthermore, with 4 meter class telescopes we catch glimpses of the fascinating new phenomena at fainter levels. An 8m and a wide-field imager (and wide-field spectrographs somewhat later) opens up a whole new type of science, reaching out to about 10 kpc in our galaxy, and redshift in the Universe. In the case of the Universe it is not known yet whether there are any galaxies of any appreciable size in existence beyond . With this new telescope the goal is to finally probe as far as one needs to go to answer a number of very old, profound questions about the origin of galaxies and of their stars.

Table 1: Major Science Goals of the Next Two Decades

Science Goal Observational Measure
Evolution of Structure, biasing galaxy correlations, weak lensing
Geometry of the Universe Supernovae, neo-classical tests
Evolution of Galaxies phi(L,z),SFR(L,z), Mergers
Star Formation in the Galaxy phi(L,z),environment
Star Formation in Nearby Galaxies SFR(L,x,y)
Low Luminosity Objects proper motions
MACHOS, Planet searches micro-lensing

The goals listed in Table 1 are not everything that one wants to know about the universe, but they represent the major astronomical issues of the next decade. Some of these goals will clearly be achieved fairly quickly and be greatly influenced by other developments in astrophysics. An example is the geometry of the Universe. Measurements of the Cosmic Background Radiation will have a major impact over the next decade. The independent information from galaxy surveys, weak lensing surveys, and supernovae will be equally important, first for breaking model degeneracies and later for independent checks that the contaminating foreground signals, such as dust in our galaxy and others, distant hot clusters of galaxies and radio galaxies were accurately removed. Other problems involving much more complex physics, such as galaxy evolution, are likely to be much more resistant to easy solution. Some problems, like planet searches, are inherently long time scale problems.


Table 2: Science Programs

Science Goal Observational Approaches
Geometry of the Universe Imaging, Gemini followup
Distribution of Dark Matter Imaging, MOS redshift surveys
Evolution of Galaxies Imaging, MOS redshift surveys
Star Formation in the Galaxy Imaging survey, MOS
Star Formation in Nearby Galaxies Imaging survey, MOS
Galactic Structure and Age Imaging, MOS
Low luminosity Objects Imaging survey
MACHOS as dark matter Imaging survey against M31
Planet searches Imaging survey against M31

A useful approach to the problem of defining telescope design parameters is to take the science goals and propose in detail how they could be answered in an observational program. These are the Design Reference Programs which provide a justification for the telescope and establish that the goals are feasible. The programs tabulated below take advantage of the wide field of the telescope to make them achievable in times of about 100 telescope nights or less. These programs are comparable in time (50-100 days) and highly complementary to some of those being proposed as Design Reference Missions for NGST, which has a 4 arcminute field.


Table 3: WF 8m Design Reference Programs

Program Area AB mag Scientific Goal
      U LSS G SF LLO M P
Wide Optical 100 26     x x x    
Deep Optical 1028xx x x x x x
UltraDeep Opt 129 xx x x      
M31 1 28     x x x xx
Wide IR 10 21 x x x xx    
Deep IR 1 24 x x x x x    
Optical Galactic 10 26     x x x   x
IR Galactic 10 21     x x x   x

Key: U: Universe, LSS: Large Scale Structure in the Universe, G: Galaxy Evolution, SF: Star formation regions in galaxies, LLO: Low Luminosity Objects, M: MACHOs, P: planets

In summary, significant access to an 8m telescope is the key tool required to be competitive in addressing the major questions of the upcoming decade. The proposed facility has unique features which are complementary to those of other large telescopes and the proposed investments in large new radio and space based facilities.

The Opportunity of a Wide-Field OIR Telescope

A valuable reference document is that of the Next Generation CFHT (NGC) committee which provides a wealth of background information. We share the long term vision laid out in that document. However, we are convinced that it is not in our interest to operate the existing CFHT for another decade. Here we advocate a specific plan for immediate action.

In the IR the blocking of starlight by interstellar dust is dramatically less than in the visible. This allows us to peer much deeper into star formation regions within our own Galaxy, as well as in other galaxies, where conditions can be quite different. Clustering of very faint galaxies at high redshifts, where the universe is so young that galaxy formation itself is just getting underway, will be studied with a full view of their environment, thereby providing complementary information to that available in the visible for nearby objects.

IR observations constitute the most powerful technique currently available for many cosmological investigations. The origin and evolution of galaxies and their clustering in the Universe is a fundamental question in astrophysics. These structures must arise from the physics of the very earliest moments of the Big Bang. No large telescopes have the field size of the telescope we propose. Moreover the advance of technology allows us, for the first time, to equip that large field with infrared detectors comparable in size and light detection efficiency of visible light detectors. No existing or planned telescope will have the capabilities of what we propose here.

The rate at which any telescope gathers data increases with its aperture, field size and image quality. Much has changed since the first 8m class telescopes were designed. Image quality that exceeds that of older 4m telescopes is achieved by 8m instruments. Wide field IR detectors are now available. Hence 8m telescopes with fields comparable to those available at telescopes such as CFHT can be fully instrumented. Imaging science has also advanced dramatically over the last decade. The HDF has played a dramatic role in the demonstration that carefully done ``photometric redshifts'' (photo-z's) and ``U band drop-outs'' (and their relations in other wavebands) can provide redshifts that are sufficiently accurate for some of the most important cosmological measurements.

The telescope we propose has 5 times the CFHT light gathering power and will have the superior image quality now demonstrated to be possible in 8m telescopes. Since the present median images in V (K) at the CFHT are 0.65 (0.50) arcseconds and the improved images at the 8m are to be 0.45 (0.35) arcseconds, for stellar objects the ratio of exposure times to the same S/N against sky noise is about 10, or one can go 1.2 magnitudes deeper in the same time. Furthermore, if a 16K rather than a 4K square IR detector is provided, even with no improvement in image quality the telescope is 80 times faster in covering sky, and another 2 times faster from the improvement in image quality. The overall result is a product of aperture and resolution elements for the telescope that will be second to none.

IR observations constitute the most powerful technique currently available for many cosmological investigations. Surprisingly, the near infrared sky is remarkably unexplored, which is mainly a consequence of the long absence of large format (many pixels) detectors, comparable in size, quality and cost with the current generation CCDs.

The 2MASS and DENIS infrared surveys are two of the first major explorations of the IR sky, and have only just begun. These are the first all sky surveys that reach a limiting magnitude of about Ks=13.5 mag and are comparable, in some ways, to work done in the optical with the Palomar Schmidt surveys of nearly 50 years ago. The latter reach low redshift galaxies and a variety of stars within our galaxy. The near infrared spectral region is so unexplored that the 2MASS survey just revealed a new type of very cool star, now designated the L class, with a temperature of about 1500K, well below that of the M stars which were long thought to terminate the spectral sequence. Many other surprises will emerge at low redshift. These new infrared surveys will be invaluable in providing the first really clear census of the stellar mass in galaxies out to a redshift of about 0.1. The telescope proposed here will be capable of large surveys detecting and analyzing the properties of objects about ten thousand times fainter than 2MASS and DENIS. To put this another way, with the new 8m, we can efficiently explore, to the same depth, a volume of the universe which is one million times larger.

The northern Gemini telescope has been optimized to work in the thermal infrared over very small fields. The LMA and NGST are specifically designed to perform prodigiously well at detecting relatively cool, dust enshrouded regions of star and planet formation. All of these facilities need to have a complementary, wide field, high spatial resolution, optical-infrared telescope to develop large statistical samples. Astronomy has been hobbled by small sample sizes until recently. Cosmology has been a leader in making use of the precision that can be obtained from large surveys, but it is clear that larger samples will be invaluable for an understanding of star formation in the great detail that is possible in nearby regions of star formation and in a more general context in other nearby galaxies. At K = 20 mag, the largest current surveys are only of order 100 square arc-minutes! In spite of the advantages of space, HST has no cooled detector allowing it to work efficiently at K. At the moment there is no telescope well designed to undertake large statistical surveys. The proposed facility is the telescope to take up this vital task.

Instruments

An important element of this proposal is a limited set of exceptionally powerful instruments that could be permanently mounted. The telescope should be equipped in the first round with full field, well sampled, optical and IR imagers. These will be able to take advantage of new sub-pixel image techniques, such as ``drizzling''. It is conceivable that later it will be possible to operate the imagers in a ``parallel mode'' using dichroic filters. In particular it would be desirable to make the IR camera usable throughout the entire month.

It should be planned to provide these instruments with wide field multi-object spectroscopy (MOS) capabilities over as large a field and as quickly as possible. Spectroscopy opens up a huge new domain of physical study which extends beyond what can be done with imaging.

Table 4: Basic Instrument Complement


Instrument Approximate Cost Completion
Megacam no new funds First Light
MegaWIR $12M First Light
OIR MOS initial $8M First Light + 3 yrs
Gecko no new funds First Light
Multi-Fibre Gecko no initial funds First Light + 2 yrs

The precise characteristics of the MOS instrument remain to be decided, based on the highest priority science objectives. However, the two most likely contenders are versions of the the multi-slit and multi-fibre spectrographs that are currently being built at several observatories. These will undoubtedly capitalize on advances in detector technology to simultaneously increase the field of view, improve the spatial sampling and expand the wavelength coverage from those currently under construction. The multiplexing advantage will be of order 102 to 104, depending on the spectral resolution required by the science. The design and construction of such an instrument requires typically six years and we envisage that it will follow the imagers by a few years to give time for the telescope and imagers to be commissioned and to get the large imaging surveys underway.

Another exciting possibility will be to adapt the Gecko coudé spectrograph to feed it with fibres to that many high resolution spectra can be acquired over a very wide field. The 8 meter telescope allows us to reach sufficiently faint objects that there will be many of them in the field. Once again we have the multiplexing advantage, and take advantage of an extremely powerful spectrograph already in place.

Engineering and Costs

We estimate that the cost of replacing the CFHT with an 8m f/6 Cassegrain will be $108M plus $20M for an initial instrument complement. Basing our telescope on existing designs saves a great deal of time and substantially reduces the risk and uncertainty in the cost and time estimates. In the following estimates we assume that Gemini will offer use `in kind' of their coating facility and expertise. To arrive at this estimate, we drew on three independent assessments to replace CFHT with a simple Cassegrain f/6:

(1) Jean Espiard, ex-Director General of REOSC, to replace CFHT with a VLT unit telescope,
(2) Matt Mountain, Director of Gemini, to reproduce a Gemini telescope,
(3) David Halliday, of Agra, to replace dome, dismantle existing telescope and provide mirror handling.

Each assessment is up to date and expressed in 1999 C$. The original of (1) was expressed in French Francs, with (2) and (3) in US$. While (1) and (2) address the total cost, (3) complements the other two by looking more closely at the details of the dismantling of the current telescope and dome and erection of a new enclosure with provision for handling the primary. Either telescope will weigh some 270 tons with a 10m track.


Table 5: 1999 C$ Cost Estimates


Item ``VLT'' ``Gemini'' Halliday best
Remove existing telescope     2.5    2.5
Telescope structure 17.0   15.6      16
Primary mirror, polishing, support 28.0   28.0      28.0
Secondary mirror & assembly 7.0   9.0      8.0
Coating chamber (if necessary) (7.5)       
Modify dome, pier, new dome etc. 9.0   21.8    26.72   26.5
Controls, software, ISS, A/G, handling   10.0      7.0
Management 13.0   9.7      10
Contingency 8.2   10.4      10
Initial instruments 20   20      20
         
Total1 102.2   124.5      128
  1. Excludes coating chamber.
  2. Replaces current dome with a ``Gemini'' dome having wind-gates plus exterior
    elevator on building to handle primary.


Apart from the costs to modify the enclosure and pier, the VLT and Gemini estimates are remarkably close. Espiard assumed that much of the existing dome and building could be used. Halliday, whose company, Agra has extensive experience in building enclosures and telescopes on Mauna Kea (Keck I & II, Subaru, Gemini) and elsewhere, writes: ``I believe that it will not be cost effective to modify the existing dome structure. The change in slot width is just too large and there would be problems in getting the ring girder geometry to work. However, I would suggest that a study be made to see if the existing dome could be salvaged cost effectively.''

The plan will be to remove the existing telescope, seal off the observation floor and make it water tight, remove the existing dome and prepare the support building for a new dome.

The new dome will follow the Gemini principle but will not contain all of the handling equipment that is presently contained within the Gemini dome. Mirror removal will be through a door placed between the arch girders at the back of the dome. From there it will be moved to grade via an external elevator.

The pacing item for the telescope will be the mirror, which will take 3 years from order placement to delivery. The other timing is estimated to be 3 months to remove the old telescope, 5 months to remove old dome and seal floor, and the time to design, manufacture, ship and erect new dome 30 months. We have in hand a quote from Schott for an 8.2m mirror blank which could be delivered in September, 2000.

The Shifting Landscape of Canadian Astronomy

Leadership and excellence in science demand access to research facilities second to none.

Canada became a leader in astronomy when the world largest telescope, the 1.8m instrument of the Dominion Astrophysical Observatory was inaugurated in 1918. Twenty years later came the 1.8m of the University of Toronto David Dunlap Observatory. Canada then fully owned two of the four largest telescopes in the world. On these Victoria and Toronto poles was built the very strong reputation of our country in a field rich in discoveries which fascinate the public and greatly enhance the prestige and technological capability of the nation. In 1974, Canada joined France and Hawaii to build the 3.6-m CFH Telescope which again propelled Canadian astronomy to the forefront, because that instrument was one of the largest and outperformed other 4m-class telescopes.

Now, a quarter of a century later, the frontiers of astronomy are being charted by 8m-class telescopes, sixteen being already in operation or under development. Through our 13.2% share in the two Gemini telescopes Canadian astronomers are guaranteed about 82 nights per year on the largest astronomical facilities. This should be compared to 730 nights on the largest facilities in the 40's and 50's and 155 nights in the 80's and 90's.

In the past, Canadian astronomers competed very successfully for time on several open 4m-class telescopes (KPNO, MMT, CTIO, WHT, AAT) as well as the Hubble Space Telescope and radio telescopes such as the VLA. We thereby increased our access to the most powerful telescopes without contributing to the capital and operating costs of the facilities. The 8m-class telescopes are not open in this same way. Concommittant with the internationalization of large astronomical facilities is the rule that access requires proportionate financial participation. This new regime simply reflects the enormous intellectual and technical resources brought to bear in the design and construction of these facilities, and also the fact that the economic activity engendered strengthens the overall technology infrastructure of the participants.

The plain truth is that Canada now lags our more aggressive peers in Europe and the USA in its per capita investment in modern optical/IR astronomical facilities.

The current situation calls into question the relevance of Canada's contributions to optical/IR world astronomy and for participation in future projects. This is why, when Canadian partnership in Gemini was being considered in 1990, the Canadian Astronomical Society urged NRC to secure funding for at least a 25% share of the project and for the maintenance of the CFH Telescope as a unique support facility. Unfortunately, the budgetary situation at that time made this impossible. The community had to be content with a contribution which now translates into a 13.2% share of the observing time. In addition, the Gemini telescopes themselves had to sacrifice their important wide-field capabilities in order to satisfy budgetary constraints. The true price of these cost-saving measures has now become apparent.

Canada still has the intellectual and technological resources to remain a leader in optical/IR astronomy, and thereby stimulate public pride in her scientific accomplishments. No other field of science has such a compelling appeal to inspire youth toward the pursuit of scientific careers. However, to retain our leadership role requires immediate investments and steadfast determination. The explosive growth of Astronomical facilities has engendered a world-wide competition for skilled technologists and leading scientists. The strong Canadian presence in these areas is well known and Canada remains vulnerable to a significant loss of its best and brightest in the absence of competitive opportunity to develop, and work with, top-flight facilities. Hence, inaction or delay carry the potential to erode our capabilities for significant future impact.

Competitive Site and Timescale: An 8m CFHT

The first choice to achieve our scientific goals of a wide field 8m telescope is to work within the existing CFHT partnership, roughly along the lines of the plans recently prepared by J. Espiard and W. Grundmann, as displayed on our frontispiece.

The CFHT partners have been vigorously yet carefully examining the Telescope's future in the near- and long-terms through the Scientific Advisory Committee (SAC), the Next Generation CFHT Committee, the Board, as well as through national committees and planning exercises. Our proposal builds upon these studies in important ways.

Why now? Why through CFHT?

Thus, what is an urgent necessity for continued Canadian astronomical excellence is equally beneficial to the CFHT partners and we propose exploring every possible way to bring our plan to fruition with them.

Our proposal complements the long-term vision elaborated in the NGC report and prepares the path to ensure that Canadians will be scientifically ready to lead in the development of the world's VLOT observatory, the engineering studies for which need to be carried out in the coming decade for implementation toward the end of the second decade of the 21st century.

The front-line lifetime of modern telescopes appears to be at least twenty years. Integrated operating costs generally exceed the capital expenditure. One could then infer that a delay of five years is not serious. But no scientific case can be made that it would be undesirable to replace the aging CFHT 3.6 m as soon as possible with a modern 8m instrument, with some twelve months of down-time.We note that the existing 3.6 meter CFHT already has a need to schedule considerable downtime to implement Megaprime and undertake a dome image quality improvement program.

Furthermore, part of the power of the proposed facility is to be in place prior to the arrival of the LMA and NGST. This is particularly important for the Canadian community where new faculty and PDFs are building their careers over the next decade. It would be most detrimental if our late arrival with an 8m, as powerful as this one is, limited our ability to respond competitively to such opportunities as the LMA, NGST and VLOT. Therefore, we cannot support a plan which calls for no action for five years.

We are also aware that there is a possibility that an 8 meter could be designed to explore a critical path of technology for a future VLOT. From a scientific point of view, however, we feel that the fastest possible replacement is the preferred strategy, and that VLOT technology be developed in other ways.

Other Options and Partnerships

The reasons for preferring to build upon the existing CFHT are fully described in the above section. Nevertheless, we are aware of, and remain sensitive to the interests and constraints affecting our existing CFHT partners: the Institute for Astronomy at the University of Hawaii and France. We also note that the Gemini directorate has expressed interest in developing a third 8m telescope, albeit in the context of a technology demonstration platform aimed at a VLOT. Here, we comment on these issues and also the prospects for alternative partnerships.

The planning discussions for the existing CFHT largely took place prior to first light at VLT (May 1998) and, of course, the more recent activities at Gemini-North and Subaru on Mauna Kea. The image quality being delivered by these new 8m is astoundingly good and it is quite clear now that CFHT (the traditional leader in image quality) is about to be supplanted by these much larger telescopes. This is an important competitive issue and the implications of these results are only now being digested.

Our conclusion, as argued in the preceding sections, is that the competitive position of CFHT, even up to the 2005 era, has been compromised. There is also widespread recognition now that the world community will not be in a position to construct a VLOT prior to 2010. The thrust of the proposal developed here is to have first engineering light in 2004 and scientific use by early-2005. There is much common ground shared by our scientific communities, which can provide the basis for discussions to implement the vision developed here. The position of the Canadian community is clear, but we do recognize that any project involving CFHT must be negotiated within the framework of the existing partnership. We also recognize that one or more new partners may have to be brought into the existing partnership in order to secure full funding of the new 8m.

Another option is to replace the CFHT with an 8m built on a different site on Mauna Kea. This has the attractive feature of permitting continued operation of the present CFHT during the construction phase, minimizing the amount of observing time lost and allowing the new wide-field CFHT instruments (Megaprime and WIRcam) to carry-out their intended programs without constraint. The cost of a building an entirely new facility may be slightly higher, primarily because of the need to pour a suitable concrete pier to support the telescope, but other cost saving features of the CFHT-based proposal remain. The most obvious possibility, which has been informally discussed with the IFA Director, is to replace the University of Hawaii 2.2m telescope. Under this option, Canadian operational support for the current CFHT would be reduced, or cease altogether (depending on our share of the new facility) upon the start of science operations with the replacement facility.

The alternative-site option need not be restricted to UH as there are two other aging 4m-class facilities on Mauna Kea; UKIRT and the IRTF. UKIRT, an infrared optimized telescope, is operated by the UK Agency PPARC through the Joint Astronomy Center in Hilo (JAC is also the management organization for the JCMT and hosts the Gemini North headquarters). Discussions with the UK on this and other partnership possibilities are to be encouraged. The IRTF is managed by the IFA on behalf of NASA and the status of this site for possible redevelopment is unknown at this time.

Some interest has been expressed by the Gemini consortium in building a third 8m telescope, partly to satisfy the expected pressure from the community for observing time, and partly to serve as a platform for demonstrating novel technology needed for the construction or operation of VLOT. This has been a traditional activity (e.g.; the ESO NTT was constructed to gain experience with an active mirror support system to be used on the VLT.) At this time, there is no clear definition of precisely what area of new technology might be incorporated into the third 8m, but some possibilities may be discerned from existing studies of MAXAT (Maximum Aperture Telescope).

Hence an option to be considered is the replacement of CFHT by the third Gemini 8m, an option that might be facilitated by the current Canadian participation in Gemini. There are, however, several factors that mitigate against this as a satisfactory response to the proposal developed here. These include:

None of the above factors are necessarily fatal and thus the concept outlined above deserves exploration if the other, simpler initiatives flounder. The attractive features here are that this option provides a path in which the design and eventual construction of a VLOT can be foreseen within the context of existing Canadian partnerships, and it offers a possible path toward rationalizing the Canadian optical/IR facilities under a common operational structure.

To summarize, the preferred path is a straightforward replacement of the existing CFHT with a new 8m, but other options, which have the potential to meet all the scientific goals defined here, do exist.

Technological Investment and Innovation for Canada

Telescope construction is a mixture of high precision fabrication, exquisite quality large optics and sophisticated control systems. Canadian and French firms have developed new capabilities through telescope construction. In the case of the Gemini telescopes, Canadian firms have won contracts that greatly exceed the Canadian investment in Gemini.

Canadian industry has the capability of doing most of the work for the proposed telescope, with the exception of the mirror. CFHT in its original incarnation helped to create a substantial product line for Agra's Coast Steel Fabricators. The technical challenges of this telescope, which is highly automated, provide new opportunities for astronomers to help move expertise from the laboratory to the economy.

Conclusions and Immediate Actions

In the next decade a number of the largest questions presented by cosmology will be addressed. We will see ``through the universe'' (if it meets expectation!). We will get a better view of the mysterious dark matter. Stellar nurseries will be unveiled. We will develop a census of extrasolar planetary systems.

It is the overwhelming interest of Canada to invest in a powerful new 8m telescope to keep its astronomical community strong for the next decade and prepared to benefit from ``world telescopes'' such as NGST and LMA by 2010. The advantages are of course observing time but also, through a largely owned telescope, a chance for our community to define its own particular approach to scientific problems and take the responsibility to make that approach work. Gemini is a powerful facility, but our minor share of it provides far fewer hours on world class telescopes than what has allowed Canada to maintain leadership in astronomy. Moreover, the planned and scientifically crucial wide-field mode of that telescope was not implemented in the final design.

As much of astronomy moves into a multi-wavelength research mode, an 8 meter, wide-field telescope becomes an essential element of an integrated network of research tools and a key ingredient in the full success of other facilities. An immediate replacement of CFHT appears to be, by far, the most efficient and most effective route toward providing such a facility for Canadian and world astronomy.

Canadians would make excellent use of the telescope, and it would still be oversubscribed, if we completely owned it. The CFHT precedent lead us to urge that Canada provide 40% of the estimated $128M cost. An absolute minimum is a 25% share.

We urge that a Working Group be established immediately. Two scientists assisted by one engineer will be needed to carry out the critical studies required to prepare this project for full funding in about a year. In particular, they will:

These will most likely include a definition of telescope and enclosure specifications, possible incorporation of components of both VLT and Gemini designs, more precision on the instrument complement, estimates of operations costs, proposals re operational mode (involving present CFHT and JACH nuclei). We suggest that this Working Group report to a committee which includes proponents of the current proposal.


Table 6: Working Group Resources for 6 months


Item Cost
1 engineer half time 45K
Engineer travel 10K
admin and tech support 13K
Partial salary for 2 scientists 54K
Scientist travel (France, UK, Australia,US, Hawaii) 30K
External contracts ( e.g.  Coast Steel) 25K
Contingency (10%) 18K
Total 195K

Submitted on Behalf of:



M. Balogh, Victoria.   W. Barkhouse, Toronto.   P. Bastien,  Montréal.   S. Beaulieu, Cambridge.   S. Blais-Ouellette, Montréal.   T. Bridges, AAO   M. Brodwin, Toronto.   R. Carlberg, Toronto.   C. Carignan, Montréal.   P. Coté, Caltech.   S. Courteau, HIA/NRC.   D. Crabtree, CFHT.   D. Crampton, HIA/NRC.   T. Davidge, HIA/NRC.   R. Doyon, Montréal.   P. Durrell, UBC.   Y. Dutil, DRE Valcartier.   G. Fahlman, UBC.   C. Foellmi, Montréal.   M. Gladders, Toronto.   P. Hall, Toronto.   D. Hartwick, Victoria.   E. Hayashi, Victoria.   P. Hickson, UBC.   J. Hesser, HIA/NRC.   M. Hudson, Victoria.   J. Hutchings, HIA/NRC.   L. Ivanescu, Montréal.   D. Johnstone, CITA.   P. Komljenovic, Victoria.   K. Labrie, Victoria.   J. Landstreet, UWO.   S. Lépine, STScI.   S. Lilly, Toronto.   N. Manset, Montréal.   C. Marois, Montréal.   F. Marleau, Cambridge.   T. Moffat, Montréal.   S. Morris, HIA/NRC.   G. Mosher, York.   D. Nadeau  Montréal.   J. Navarro, Victoria.   D. Patton, Victoria.   C. Pritchet, Victoria.   H. Richer, UBC.   M. Sawicki, Caltech.   N. St-Louis, Montréal.   A. Sigut, UWO.   L. Simard, Santa Cruz.   G. Squires, Caltech.   R. Racine, Montréal.   J.-R. Roy, Laval.   P. Stetson, HIA/NRC.   S. van den Bergh, HIA/NRC.   G. Wade, Toronto.   G. Walker, UBC.   T. Webb, Toronto.   M. West, St. Mary's.   H. Yee, Toronto.  


This is a partial list based on those contacted during the proposal development.



Ray Carlberg
1999-03-11


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