The Thirty Meter Telescope (TMT) is a segmented-mirror telescope that extends the legacy of the audacious 10m Keck telescopes and the Gran Telescopio Canarias. TMT is in an advanced stage of design with many components, including mirror segments and their support systems being manufactured today. The telescope will have a high-performance multi-conjugate adaptive optics system to approach the diffraction limit of angular resolution set by the physics of light (an astonishing 0.0055 arc seconds at 800nm). The combination of extremely large aperture, diffraction-limited performance, and mature design led the U.S. National Academy’s ASTRO2020 Decadal Survey to make extremely large telescopes their top priority.

The TMT is designed for outstanding performance with high throughput, a clean aperture, and a rigid structure that provide some advantages over the European ELT. The TMT’s unprecedented imaging capability and sensitivity open a wide range of scientific applications ranging from searching for signs of life on exoplanets, to testing the physics of black holes, to tracing the effects of dark matter and dark energy as spelled out in the 2024 Detailed Science Case (https://www.tmt.org/download/Document/10/original).

The TIO Member institutions include Caltech, Canada, India, Japan and the University of California. TIO presently has Design and Development funding from the US National Science Foundation. Constructing TMT at Northern Hemisphere site like ORM would bring the power of ELTs to cover the whole sky.