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The 1995 Magellan Proposal

A proposal to seek partnership in the MAGELLAN twin-6.5m telescope project
The Department of Astronomy, University of Toronto
August 1995

 

Executive Summary

Investment in a new telescope facility is necessary to secure the long term future of observational astronomy and astrophysics, a central physical science, at the University of Toronto. The previous investment in the Department of Astronomy’s David Dunlap Observatory (DDO), constructed in 1935, is the springboard that will allow us to develop the new facility.The MAGELLAN project is constructing two giant 6.5m telescopes on the Las Campanas mountain in Chile. These telescopes, part of a new generation of unprecedentedly large telescopes being built around the world, will produce dramatic advances in astronomy, and particularly in our understanding of the origin and evolution of planets, stars, galaxies and the Universe as a whole.

The partners in MAGELLAN (The Carnegie Institution, Harvard and the University of Arizona) are seeking two additional partners to secure the completion of both telescopes. A 10% share in this partnership would require a capital investment of approximately $CAD 11M. In return, 60 nights per year of observing time per year would be available to UofT astronomers.

This telescope project is particularly attractive to the Department of Astronomy because:

  • The MAGELLAN telescopes are optimized for spectroscopy of large numbers of very faint objects over a wide field of view. This makes them particularly suited to research in observational cosmology, one of the Department’s existing strengths, the area identified for the proposed new endowed Chair, and an area that is powerfully complementary to the theoretical research in cosmology carried out at CITA.
  • As well as securing guaranteed access to what will be two of the world’s largest telescopes, access will also be gained to 2.5m and 1.0m telescopes on the same site, thus satisfying the aspirations of the entire observational research community in the Department.
  • The involvement in the instrumentation program for these telescopes would require the full participation of the DDO, and this will provide the focus for a rejuvenated Observatory within the UofT. The instrumentation program would provide opportunities for collaborations with other UofT Departments.
  • There is a long standing partnership between UofT and Carnegie because the UofT’s Southern Observatory is located on Las Campanas.
  • The fund-raising approach builds upon a previously developed fund-raising strategy.

Access to the Magellan telescopes (and other smaller telescopes on the same site) would assure the scientific pre-eminence of the Department of Astronomy in the first decades of the next century and would represent a focus for a rejuvenated David Dunlap Observatory, thus relaunching the original 60 year old Dunlap gift.

1. Introduction: Perspective and Rationale

This document introduces a new proposal for a fund raising initiative by the Department of Astronomy. It reflects a new opportunity now open to the Department and the David Dunlap Observatory (DDO). It builds upon our previous initiative involving the construction of a new 2-3m telescope in Chile, but now with emphasis on joining as a partner in a more ambitious project. This would greatly extend the scientific potential, and would involve a partnership with some of the world’s front-ranked institutions of teaching and research. Particular emphasis is laid in this proposal on the critical need for an initiative of this kind to rejuvenate the scientific and technical potential of the DDO, which is now sixty years old.

The proposal is to enter into a consortium with the Observatories of the Carnegie Institution of Washington (OCIW), Harvard University, the University of Arizona, and possibly Columbia University or the University of Michigan, to complete construction in Chile of two telescopes which will be amongst the world’s largest and most advanced. The project is underway, and the University of Toronto has been invited to participate as a partner at the 10% level, if we can secure the required funding soon, i.e. within 1-2 years. The opportunity thus afforded this University by Carnegie recognizes the intellectual strengths both in the Department of Astronomy and in the Canadian Institute of Theoretical Astrophysics (CITA). The project also provides opportunities for collaboration with cognate departments both in the instrumentation and in the scientific programs to be carried out on the telescope.

In our previous submission for fund-raising to construct our own telescope in Chile, little emphasis was placed on the essential need for such an initiative to revitalize the DDO, whose technical resources would be largely focussed on such a project, because of the limited format available. To place this argument in perspective, the 1.9m telescope of the DDO was the second largest in the world when it was commissioned in 1935. It was the vision and the fundraising efforts and skill of Clarence Augustus Chant, one of only two faculty in the Department at the time, that permitted the establishment of the DDO as a gift from Jessie Donalda Dunlap. The cost in today’s terms would be $10M. What is envisioned in the present proposal is simply to raise an equivalent amount to place the DDO once more in the front and leading ranks of the field.

Every university in North America with a Department of Astronomy the stature of Toronto’s either has private access to a major modern telescope facility, or is fund-raising to gain such access. To this end, the Department of Astronomy has developed a clearcut strategy over the past ten years, particularly in relation to establishing a facility in Chile, the site of the two giant telescopes in this proposal. The Department of Astronomy now asks that it be given an opportunity by the University to implement this strategy, under whatever category appropriate, in a timely manner so as to bring our top priority project to fruition.

The experience of the past very clearly demonstrates that a successful project of this nature and magnitude has a profound influence on the quality of the academic program, the research of our graduate students, and the recruitment of new faculty (which will be needed in the post-2000 period to replace many retirements). Given that the University already has the DDO and thereby the resources to support such a project, we urge that this proposal be given the priority needed for it to proceed.

2. A new initiative for the David Dunlap Observatory

2.1 Pressures on the existing DDO 1.9m telescopeIn recent years, the DDO 1.9m has faced increasing competitive pressures. First and foremost, as the cost of travel and communications has dropped, superior observing sites have been developed at remote locations (most notably in Hawaii in the northern hemisphere and in Chile in the south) and the attractiveness of “local” sites, deemed essential in the 1930’s, has declined. In addition, the growth of Toronto and the resulting increase in light pollution has degraded the quality of the Richmond Hill site for astronomical research. The increasingly obvious limitations of the DDO site led to the establishment in 1970 of a 0.6m telescope at the University of Toronto Southern Observatory (UTSO) located on the superb Las Campanas mountain in Chile. Second, the 1.9m telescope is now, at an age of 60 years, a very old telescope which has been surpassed by many telescopes of much larger size and of more modern design (see the figure in the Appendix). Finally, the discipline of astronomy and astrophysics has itself changed dramatically over the last 60 years, and the DDO is not suitable for many currently promising research areas.

Thus, whereas 15 years ago the DDO represented the focus of the research efforts for most of the faculty at the Department of Astronomy, the DDO is now suitable only for a limited range of observations. Since 1980, the new faculty in astronomy at UofT have primarily been theoreticians (cross-appointed to CITA) or observers working in areas requiring the use of large telescopes located at the best sites overseas or in space (e.g. the 3.6m Canada France Hawaii Telescope in Hawaii and the Hubble Space Telescope). While the Observatory has continued to be scientifically productive in some areas and while it maintains a vigourous public awareness program (with 5000 visitors annually) it no longer satisfies the scientific aspirations of the majority of the faculty.

Clearly, the long-term health of the Department of Astronomy will require us to be able to attract the very best graduate students, and particularly after the year 2000, to recruit world- class faculty to replace retirements. It will be increasingly difficult to maintain expertise in many areas of Astronomy and Astrophysics in the absence of competitive observational facilities.

2.2 The DDO as a base for offshore operations

As already demonstrated by the successful operation of the UTSO (a facility which attracts NSERC support at the level of $100k p.a.) the existing infrastructure at the DDO provides a natural base from which a remote offshore observatory can be supported. Development and testing of instrumentation for a remote telescope can be carried out locally, using the intellectual and technical resources of the DDO and the wider University community, before the instruments are shipped overseas.

A new investment in a modern observational facility at a comparable level to the original Dunlap gift (of order $10M in 1995 dollars) will both satisfy the research aspirations of the present and future research faculty in our rapidly evolving discipline, and provide a focus for a rejuvenated DDO. Indeed, the initial investment in the DDO made 60 years ago provides the springboard for the new endeavour.

2.3 A new telescope initiative for the DDO

In view of this, the Department of Astronomy has studied and pursued to various degrees a number of different telescope projects over the past decade. This multiple approach is appropriate given the wide and changing nature of modern astronomical research, the limited windows of opportunity that exist for different projects and the various funding possibilities that can be identified for each. These options have included participation with Caltech in the Owens Valley Radio Interferometer and construction of a 2-3m class telescope in Chile, possibly in partnership with the University of Chile. This latter arose from a desire to have guaranteed access to a telescope for long-term in-depth projects that are difficult or impossible to carry out on shared international facilities (see below) and the perception that a telescope in the 2m to 3m class was the largest that the Department could realistically manage on an offshore site on its own.

Recently, a new and particularly attractive opportunity has emerged which has received unanimous support from the faculty of the Department of Astronomy. This is partnership (with the Carnegie Observatories, Harvard and other U.S. Universities) in the twin-6.5m MAGELLAN telescopes to be built on Las Campanas in Chile. The MAGELLAN telescopes will be two of a whole new generation of unprecedentedly large optical/infrared telescopes that are being built around the world and which are set to revolutionize our understanding of many areas of astronomy. As discussed below, participation in MAGELLAN is particularly attractive because:it will give privately controlled access to two of the largest telescopes in the world. These telescopes are being optimized for observational cosmology, one of the most exciting current research areas, one in which the department already excels, and one which complements the theoretical strengths of CITA. In addition, participation in MAGELLAN would also give access to large blocks of time on the smaller 2.5m and 1.0m telescopes operated by Carnegie on the site which would represent further flexibility in the observational resources available to the entire research community at UofT.

3. The new generation of large optical/infrared telescopes

Although great strides in our understanding of the Universe have been made using space- based observatories working in the X-ray, ultraviolet and far-infrared wavebands, conventional optical/infrared telescopes on the ground still dominate astronomical research because of their cost-effectiveness and flexibility and because of the rapid developments in detector and instrument technology continue to enhance their performance.3.1 New telescope projects

The present time represents a period of particularly rapid growth and investment in ground-based optical/infrared astronomy. Between 1990-2000, more than $1.5 billion will be invested in a new generation of giant telescopes, including MAGELLAN, that are being constructed in Hawaii and Chile. These telescopes, listed in the Appendix, will operate in the optical and infrared wavebands and have apertures in the 6m-10m range (the power of a telescope is broadly speaking proportional to the square of its aperture). The construction of telescopes of this size has had to await the development of new engineering approaches to the fabrication and support of immense mirrors.

Although they may be used to address a wide range of astronomical research questions, these telescopes are particularly well-suited to the study of young stars, to the detection and study of other planetary systems and to the study of large numbers of exceedingly remote galaxies and gas clouds in the early Universe. The construction of these giant telescopes has been largely motivated by the expectation that answers to fundamental questions concerning the origins of planets, of stars, galaxies and indeed of the Universe itself are now observationally accessible and that our theories regarding these events can be rigourously tested. The first results from the Keck 10m telescope in Hawaii which became fully operational in 1995 have underscored the immense potential of this new generation of telescopes.

3.2 The importance of privately controlled telescopes

Many of these new large telescopes have been funded by national governments or consortia of them. One example is the GEMINI project which is constructing two 8-m telescopes, one in Hawaii and the other in Chile. Canada, through contributions from NSERC and NRC, is a 15% partner in GEMINI. However, as shown in the Table in the Appendix, roughly half of these large telescope projects are being privately funded by U.S. universities and other institutions. This is because qualitatively different science is possible on privately operated telescopes, for the following reasons:

  • The user community for national facilities is so large that there is very strong pressure to allocate the observing time as widely as possible through the community (if only to secure continued political support for the facility) and thus observing time is allocated in small amounts, even to the most meritorious projects. This makes it difficult to acquire in a timely manner the large body of data often needed for the most productive in-depth studies.
  • Correspondingly, instrumentation on such telescopes must be usable for a wide range of science observations and furthermore must be operable by relatively inexperienced observers. Such instruments can therefore not be optimized for particularly demanding observational programs and are also more expensive (since they must be both more complicated and more automated).
  • Because of the wider user community and associated inflexibility in scheduling the telescope, it is generally extremely difficult to accommodate scientific programs which require unusual scheduling of the telescope, such as the immediate follow-up of transient events, the use of periods of exceptionally good observing conditions, or the extended monitoring of sources over long periods of time.
  • The committees allocating observing time on national facilities have a tendency to favour cautious research producing predictable results. Access to private facilities offers a way to take scientific chances that can produce breakthroughs in research.

In short, the smaller user community of a privately operated telescope allows more focused and fundamental science to be carried out more cost-effectively.

4. The MAGELLAN twin-6.5m project

The MAGELLAN project is at present a partnership between The Observatories of the Carnegie Institute of Washington (OCIW) (located in Pasadena, California), Harvard University, and the University of Arizona. The OCIW, who are leading the project, have a long history of constructing the world’s largest telescopes (including the Hooker 100″ telescope in 1917, to which the DDO 1.9m was second in size, and the Hale 200″ at Palomar built in 1948). Funding is currently committed for the construction of one 6.5m telescope on Las Campanas, the site of our own UTSO as well as a 1.0m and a 2.5m telescope operated by OCIW. Construction for MAGELLAN has now started in Chile.However, due to savings in duplication, a second telescope can be built at the same site for less than the cost of the first, provided the order is placed early enough. In addition to the economies of scale in both capital and operating costs involved in having two almost identical telescopes on the same site, the instrumentation on each can be optimized for particular projects allowing long uninterrupted observing runs. In the long term, the emerging technology of interferometry at optical and infrared wavelengths can be used to link the telescopes together to form an interferometer capable of very high resolution imaging.

The total cost of the two-telescope project is roughly $US 84M of which all but $17M has been raised from the original partners. The original partners are therefore seeking the participation of other institutions in the project. The University of Toronto has been invited, along with other institutions in the US, to join the project. The missing $US 17M represent a 20% share in the two-telescope project and it is currently envisaged that this will be raised by two institutions contributing roughly equal shares in the $US 7-10M range and thus each securing a 8-12% stake in the project. In addition to their capital share, partners would be expected to make a cash contribution towards the operating expenses of the observatory ($US 170k p.a. for a 10% share) and to participate in the provision of instruments for the telescopes. In return for their financial contributions, the partners receive a pro-rated share of the telescope time to use as they choose.

The approach by OCIW to the UofT is based on the scientific strengths of the UofT astronomical community and their compatibility with those of OCIW, and on the potential of the DDO as a contributor to the instrumental program.

At present both Columbia University and the University of Michigan are known to be seeking the required funds. In order to secure the savings inherent in the second telescope, the extra funding must be in place soon (and certainly within the next two years). Participation in MAGELLAN is, understandably, on a “first-come first-served” basis.

The design of the MAGELLAN telescopes is outwardly conventional but has several novel features. Whilst retaining flexibility of use and operation through rapidly interchangeable focal stations, the optical design has been optimized through the use of a Gregorian secondary mirror to produce the most efficient spectroscopy of faint objects over a very wide field of view. This is a key capability that is absent in the designs of the other large telescopes being built and will mean that many of the most exciting projects, including the carrying out of large scale redshift surveys to map the distribution of galaxies on the largest scales, to study their evolution with cosmic epoch and to determine the cosmological parameters, are likely to be carried out on MAGELLAN. The primary mirror is a fast f/1.25 borosilicate honeycomb mirror produced by the Mirror Labs at the University of Arizona. This type of lightweight mirror has been proven in the ARC and WIYN 3.5m telescopes, and has been successfully cast and polished at the 6.5m size for the MMT Upgrade project, and thus poses little technical risk.

5. MAGELLAN in the UofT context

While any large telescope project would be an exciting and attractive prospect for any institution, the MAGELLAN project is particularly well-suited to the University of Toronto for several reasons:Strengthening existing scientific interests: As noted above, the MAGELLAN telescopes will be an outstanding instrument for the systematic study of very large numbers of faint galaxies at high redshifts, a research area in which UofT astronomers are already playing a leading role. The general emphasis of the project on observational cosmology matches well the proposed Chair in Observational Cosmology in the Department of Astronomy. It also complements the theoretical strengths of CITA which has emerged as one of the premier centers in theoretical cosmology in the world.

Access to other facilities on Las Campanas: The fact that OCIW already operates two smaller telescopes (2.5m and 1.0m) on Las Campanas would allow UofT astronomers access to southern skies on 2m class telescopes if we joined the MAGELLAN project, because time on the 6.5m telescopes could be traded for larger blocks of observing time on the OCIW 2.5m. In terms of collecting area, 6 nights on the 6.5m telescope (a tenth of the proposed UofT share in MAGELLAN) is equivalent to 40 nights on the 2.5m. This access would be of wide scientific interest, especially to those members of the Department studying relatively bright stars. The immediate gains from linking the two MAGELLAN telescopes into an interferometer will also be felt by this latter community.

Complementarity with Gemini: The wide-field design of the MAGELLAN telescopes is exquisitely complementary to the design of the two GEMINI telescopes (to which UofT astronomers will already have access through Canada’s 15% stake). The GEMINI telescopes have been designed to produce exceptional image quality over a narrow field of view and will be used to study small numbers of faint objects in great detail. Thus in no sense would participation in MAGELLAN simply duplicate the access to GEMINI that UofT astronomers will gain through the Canadian participation in that project.

Utilisation of the DDO: The clear expectation that partners will bring forward instruments for the telescopes from their institutions will provide an intellectual focus and stimulus to the DDO. This is not a project in which telescope time is simply bought with cash contributions, and MAGELLAN will assure the future development and vitality of the DDO.

Interdisciplinary activity: The development of forefront optical/infrared instrmentation for MAGELLAN opens up possibilities for collaboration with cognate departments in the area of opto- electronics (e.g. the Departments of Physics and Electrical Engineering). In addition, many of the research areas to be pursued involve inter-disciplinary study. As examples of departments which would be interested in research on MAGELLAN, the study of star-forming regions provides opportunities for the study of gas phase chemistry which is thought to play a key role in the star- formation process (Department of Chemistry) while the distribution of galaxies on very large scales is thought to reflect the results of fundamental physical processes occuring in the very early Universe (Department of Physics).

Partners of recognised strength: The partners in Magellan have operated on Las Campanas for many years and have been leaders in the operation of large telescopes for most of this century. While participating fully in the intellectual development of the telescope and its instrumentation, and while retaining full control over the scientific use of our share of the telescope time, the UofT would be spared the responsibility of most of the day-to-day running of a major offshore operation.

Partnership with Carnegie Observatories: The links between OCIW and UofT are already very close. The presence of the 0.6m UTSO on the Las Campanas site has assured a long standing relationship between the two institutions. In addition, the similarity of the scientific interests of many of the staff at OCIW and at UofT has ensured a long history of scientific exchanges.

6. Fundraising strategies

Due to the extended period over which the need to rejuvenate the DDO has been apparent, the Department has already identified several promising opportunities which could produce a substantial bequest of the required amount (approximately $CA 10m) and extensive contacts have already been made.A unique aspect of both MAGELLAN and the smaller telescope project mentioned above is the connection with the country of Chile. There are a total of 40 or so Canadian companies that have invested some $3.5 billion in Chile (mostly in mining activities). At the political level, the Canadian ambassador in Chile, Marc Lortie, has been particularly supportive of our telescope initiatives and has had several meetings with Departmental representatives visiting Santiago. He supplied the details of the Canadian investments in Chile to the Department, and has offered to help in any way he can. The Chilean connection is particularly timely given the proposed accession of Chile to NAFTA, and in this regard the UTSO was mentioned by the Prime Minister during his recent speech to the Chilean Parliament.

Ever since the establishment of the UTSO, the UofT has had a tangible intellectual link with the Chilean astronomical community through a Graduate Fellowship for Chilean students studying for a PhD at UofT. The students receive a stipend from the Department and a Fee Waiver from the University. In this way, a series of Chilean students have received PhDs from UofT, including several now holding senior positions within the Chilean astronomical community.

In the context of the previously proposed 2-3m telescope, it was envisaged that a joint approach to the Canadian companies operating in Chile could be made by UofT and the University of Chile for a shared telescope. In the case of MAGELLAN, this would be less appropriate since Chilean astronomers will already receive 10% of the telescope time by virtue of being the host country. Thus, a better approach might be to foster collaborative projects, perhaps through the establishment of a rotating faculty position in Toronto (possibly the proposed Chair in Observational Cosmology) to be occupied by a Chilean visitor, and to seek funds to enable us to match the telescope time that the Chileans would already have. If the Chilean and Toronto time was combined and used for a small number of collaborative projects then the combined share would allow some truly remarkable research projects to be undertaken.