Large Fiber Array Spectroscopic Telescope (LFAST)

LFAST Pier Evaluation Services [ Steward Observatory, University of Arizona, Kitt Peak National Observatory, Arizona ]

The Large Fiber Array Spectroscopic Telescope (LFAST) is an innovative concept under development by Steward Observatory at the University of Arizona. Rather than relying on a single large primary mirror, LFAST employs an array of small, identical telescopes whose combined light is routed via optical fibers to a central spectrograph, enabling exceptionally large light-collecting capability at a fraction of the cost of a conventional extremely large telescope. To advance a working prototype, Steward Observatory identified an existing telescope pier at Kitt Peak that could be usable for the project, requiring careful evaluation of the existing concrete structure for code compliance and adequacy under the environmental loads anticipated at the site under the proposed telescope.

M3 provided a comprehensive pier evaluation encompassing an as-built site visit and structural condition assessment. Our structural engineering team assessed the pier’s fundamental frequencies and anticipated deflections, both critical factors in evaluating the optical performance of the telescope. The evaluation required coordination with the Tohono O’odham Nation for on-site work through its TERO exemption process, and delivered clear findings supporting the project team’s path forward.

Building on this initial engagement, M3 is continuing work with Steward Observatory on the next phase of the LFAST project, assisting in developing and refining the telescope-to-pier interface design. This scope encompasses anchorage, mounting geometry, and the structural detailing required to integrate the LFAST prototype with the existing pier, bridging the gap between feasibility evaluation and physical implementation of this novel telescope concept.