- TROPO - LATMOS
- TRW Inc.
- Taras Shevchenko National University of Kyiv
- Technical University of Berlin | Technische Universität Berlin
- Technical University of Lisbon
- Technion - Israel Institute of Technology [Haifa]
- Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig]
- Technische Universität Munchen - Technical University Munich - Université Technique de Munich
- Telescopio Nazionale Galileo
- Texas A&M University [College Station]
- The Auroral Observatory
- The Belgian User Support and Operations Centre
- The Boeing Company, Huntington Beach
- The George Washington University
- The Key Laboratory of Ocean Remote Sensing
- The Open University [Milton Keynes]
- The University Centre in Svalbard
- The University of New Mexico [Albuquerque]
- The University of Sydney
- The University of Tokyo
- Thüringer Landessternwarte Tautenburg
- Tohoku University [Sendai]
- Tokushima Science Museum
- Tokyo Institute of Technology [Tokyo]
- Trent University
- Tshwane University of Technology [Pretoria]
- Télescope héliographique pour l'étude du magnétisme et des instabilites solaires
- the Russian Academy of Sciences [Moscow, Russia]