The Status of the Thirty Meter Telescope Project

Invited Paper

The Status of the Thirty Meter Telescope Project Jerry Nelsona, Gary H. Sandersb a University of California, Santa Cruz CA 95064 , b TMT Project, 2632 East Washington Blvd, Pasadena, CA, USA 91107 ABSTRACT The Thirty Meter Telescope (TMT) Project will design and build a thirty-meter diameter telescope for research in astronomy at optical and infrared wavelengths. TMT is a partnership between the University of California, Caltech, and the Association of Canadian Universities for Research in Astronomy (ACURA). The $80 million TMT design and development phase is fully funded and Preliminary Design is in progress. An additional $300 million has been pledged towards early TMT construction which will commence in 2009. We include a high level description of the design of the telescope and its planned adaptive optics and science instrumentation. The schedule of key milestones for completing the design and construction is summarized. Keywords: TMT, telescope, project, status, thirty-meter 1 INTRODUCTION The TMT Project is undertaking the ambitious objective of designing and building a telescope with 9x the collecting area of the world’s current largest telescope, the 10-m Keck telescope. TMT will have unprecedented light gathering power and angular resolution. To achieve these goals the telescope must be of sufficiently high optical quality that the Earth’s atmosphere sets the limits to the optical performance. To achieve the potential of this telescope we incorporate an adaptive optics (AO) system to allow diffraction-limited imaging, and a suite of science instruments to carry out the science programs envisaged for TMT. The TMT is an outgrowth of earlier studies by several groups. CELT1 carried out a set of studies for a 30-m segmented mirror telescope, sponsored by the University of California and Caltech. GSMT2 was a comparable study carried out by the National Optical Astronomy Observatory (NOAO/AURA). VLOT3 was a study for a 20-m telescope carried out by our Canadian partners. As a result of these studies, the scope of such a telescope became clear and motivated the University of California, Caltech, and ACURA to form a partnership to design and build the TMT. Since 2004, the TMT partnership has been vigorously proceeding in a design development phase to produce a design, cost estimate and schedule for construction. At the same time, risk reduction activities have been underway for key risk areas that could potentially have a large impact on feasibility, cost or schedule. Since our report to the 2006 SPIE conference4, the project has completed the conceptual design and cost estimate activity, carried out an extensive value engineering activity that resulted in an improved design at reduced cost and has delivered an externally reviewed Detailed Science Case5, an Observatory Requirements Document6, an Observatory Architecture Document7, an Operations Concept Document8 and a detailed TMT Construction Proposal9. Following this completion of the conceptual design, the project initiated the Preliminary Design phase during which the particular detailed designs are advanced and assessed against the science and technical requirements. Key long-lead and risks items are being manufactured as prototypes or first articles. These include primary mirror segments and support systems as well as key adaptive optics components. Recognizing the size of the Project, a strong systems-engineering approach has been taken to reduce performance, cost and schedule risk. The Project work and deliverables are divided into major categories as can be seen in Table 1-1. Based on this detailed Work Breakdown Structure (WBS), planning and engineering efforts are underway to design the TMT to well-defined technical requirements as well as schedule and cost goals. We are well along towards meeting these challenges.

Ground-based and Airborne Telescopes II, edited by Larry M. Stepp, Roberto Gilmozzi, Proc. of SPIE Vol. 7012, 70121A, (2008) · 0277-786X/08/$18 · doi: 10.1117/12.788238

Proc. of SPIE Vol. 7012 70121A-1 2008 SPIE Digital Library -- Subscriber Archive Copy

The high level schedule of the TMT is shown in Table 1-2. Site construction is planned to begin in 2010 with first science in 2018. The details of the schedule will depend on the selected site and the actual flow of the construction funds. The design-to-cost target for TMT is $760M in FY2006 economics10. This estimate includes a 26% contingency, based on detailed estimates of risk areas. A thorough cost review in September 2006 confirmed the suitability of the cost estimate and costing methodologies and underscored those areas of high potential cost risk and cost savings. WBS Element (