Rendering of TMT Telescope Structure -
The Thirty Meter Telescope (TMT) Telescope Structure serves as the framework onto which all other subsystems (mirrors, science instruments, cables, refrigerant lines, laser guide star facility, etc.) get attached. The telescope structure is divided into two main rotating systems: the azimuth and the elevation structures. The azimuth structure supports the elevation structure and the multiple scientific instruments located on the two Nasmyth platforms. The telescope, about 50 meters tall and 55 meters wide, will be enclosed within a very compact dome. It will weigh close to 3000 metric tons and will be capable of completing a full azimuth rotation in less than 3 minutes -
Image credit : TMT International Observatory
Pasadena, CA – TMT’s telescope structure subsystem (STR) recently completed two successful Production Readiness Reviews (PRR2 and PRR3) to assess the availability of adequate resources and planning for production, and later for assembly, integration and verification. The STR’s design and future fabrication are activities led by NAOJ and their prime contractor Mitsubishi Electric Corporation (MELCO) in Japan.
TMT STR PRRs 2 & 3 meetings in Japan - An international panel of reviewers from MELCO-NAOJ-TIO, outside the Mitsubishi Electric Corporation (MELCO) facility in Amagasaki, Japan, met for important production readiness reviews for the TMT’s Structure. The reviews were attended by leading scientists and engineers from both continents, on February 16 and 17, 2023 (JST) - Image credit: TMT International Observatory
The TMT Telescope is an altitude over azimuth design with a single azimuth track (horizontal rotation) and two large elevation journals (vertical rotation). TMT’s STR will securely hold all TMT mirrors precisely in place under any circumstances and support all science instruments. It will also enable precise pointing and tracking of any objects in the night sky and keep all mechanical and optical components aligned to achieve the best possible observations.
While PRR2 dealt with the elevation and azimuth structures of the telescope (the main moving parts of the telescope and weigh about 2000 metric tons), the PRR3 review focused on the Nasmyth platforms (3rd floor level which give access to the laser guide star facility plus the cryogenic platform and the large 4th floor level where all science instruments are seated).
TMT’s large STR serves as the framework of the telescope and thus interfaces with all telescope mounted instrumentation, optics, software, and control subsystems. The verification of the STR interfaces with all other subsystems, and production drawings and documentation were carried out by TMT Systems Engineering (SE) and Quality Assurance & Safety teams.
"NAOJ and MELCO teams in Japan have been working very hard with TMT’s System Engineering team on the telescope structure development and updating the TMT Interface Control Document product to make sure the project is ready for these readiness reviews,” saidMike Sheehan, Chair of the review and group leader for TMT Enclosure.
TMT STR PRRs 2 & 3 meetings in Japan - Overview of meetings including MELCO-NAOJ-TIO teams held at the Mitsubishi Electric Corp. facility in Amagasaki, Japan on February 16 and 17, 2023 (JST) - Image credit: TMT International Observatory
A significant part of TMT’s design and construction is provided by in-kind contributions led by TMT-Japan which has been involved in the project since the beginning. TMT partners in Japan have retained the proficiency and intellectual property developed over many years by MELCO with a high level of expertise in building telescopes.
Successfully passing these reviews is an important step forward, not only validating the production readiness of the TMT structure itself but also for the TMT Project and TMT partners. “TIO is grateful for NAOJ's support of the telescope structure work and progress made by MELCO to achieve these major STR PRRs 2 & 3 milestones,” expressed Kyle Kinoshita, leader of the STR group at the project office. “Working with MELCO is a huge asset for the TMT Project.”
As Masahiro Sugimoto, NAOJ STR group leader, noted in his debriefing remarks, “the scope of these PRRs encompass the majority of the main structure elements and completing this work achieves a significant STR and TMT milestone.”
“Thank you to the TMT STR Design and SE Teams, Review Panel and Observers for their intense efforts to prepare for, and successfully conduct STR PRRs 2 and 3,” saidFengchuan Liu, TMT Project Manager. “Also, a special acknowledgement to the Review Panelwho performed a thorough and objective evaluation of all review materials and provided the Design Team and TIO helpful recommendations!”
TMT STR PRRs 2&3 Meetings in Japan - The NAOJ-TIO Telescope Structure design team meeting at the Mitsubishi Electric Corp. facility in Amagasaki, Japan on February 16 and 17, 2023 (JST) - Image credit: TMT International Observatory
