SPIE Astro 2024: Thirty Meter Telescope Observatory awards contract to AMOS

20 Jun 2024

To design and build the TMT Tertiary Mirror Support System and Positioner Assembly.

by Matthew Peach in Yokohama

Artist’s rendering of the pending TMT to be installed on Maunakea, Hawai’i.

The Thirty Meter Telescope International Observatory (TMT) has awarded a contract to Belgium-based telescope and space equipment developer AMOS for designing and manufacturing the tertiary mirror support system and positioner assembly (M3SSPA) of the future extremely large TMT telescope. Terms of the contract were not disclosed.

Once constructed, the TMT telescope will have a 30-meter primary mirror and be the largest ground-based, optical telescope in the Northern hemisphere. With its primary site located on Maunakea in Hawai’i, TMT is one of three extremely large telescopes currently under construction in the world.

The TMT will offer astronomers a window to the Universe with unprecedented quality and depth. The primary mirror will be 30m across – making it among the largest optical-near infrared telescopes to be built in the coming decade.

Liege-headquartered AMOS has this week been exhibiting at SPIE Astronomical Telescopes + Instrumentation, in Yokohama, Japan, the technical event for ground-based, airborne, and space-based telescopes, and their supporting instrumentation.

AMOS offers a range of opto-mechanical systems for space and astronomy. It delivers to observatories worldwide astronomical telescopes, solar telescopes, interferometer units, telescope subsystems, mirrors, and other optical elements needed for such instruments.

The company stated, “Building such a telescope is a major challenge. Engineers must design and build large moving structures capable of holding the telescope’s different mirrors in place with nanometric precision.”

Rendering design of the TMT Tertiary Mirror System (M3S).

After being chosen to design the secondary mirror support system and positioner, AMOS will also be developing another key part of the telescope: the tertiary mirror support system and positioner assembly, known as the “M3SSPA”.

This system consists of a large mount that carries and orients the M3 mirror. Located on a tower emerging from the center of the 30-meter primary mirror support structure, the tertiary mirror captures the light reflected by the secondary mirror at the top of the telescope, and transmits it towards one of the two Nasmyth platforms on the side of the telescope, where the scientific instruments are located.

The M3SSPA system comprises two elements: a system to support the 3.6 x 2.5-meter elliptic flat tertiary mirror and ensure that the mirror’s surface keeps its optimal shape with a precision in the order of a fraction of a micrometer; and a positioning mechanism allowing the mirror to direct the beam with a high precision towards the telescope instruments and to flip 180° so as to illuminate the instruments on one or the other side of the telescope, depending on the observations to be made.

Xavier Verians, AMOS’ Business Development Director, commented, “We are excited to initiate the work on this second major TMT subsystem. TIO’s requirements are challenging but AMOS was selected because of our proven reliability and the strength of our proposed plans to develop the M3SSPA.”

About TIO

TIO’s members are the California Institute of Technology, University of California, the National Institutes of Natural Sciences of Japan, the Department of Science and Technology of India, and the National Research Council of Canada.

The Association of Universities for Research in Astronomy is an associate member. Major funding has been provided by the Gordon and Betty Moore Foundation. The U.S. National Science Foundation has provided funding for recent design and development work.