A dominant problem for large, high precision telescopes is the deformation due to temperature changes
in the structure. Even for active surface designs such as the Large Millimeter Telescope/Gran Telescopio
Milimetrico (LMT), accurate knowledge of the temperature distribution in the structure is necessary in order
to adjust the primary reflector panels and make pointing corrections.
The design of thermal management system of the LMT consists of a fully-cladded structure, a forced
ventilation system, and a collection of temperature sensors distributed throughout the telescope. During
the design, both steady-state and dynamic thermal models were developed to predict the thermal behavior.
Additionally, some thermal measurements were taken during construction, before the cladding was installed.
Since the structure is now completely enclosed with insulating cladding, it is an excellent candidate for
thermal imaging at this stage of the commissioning. Thermal images of the structure are presented, showing
the actual temperature distribution of the LMT alidade structure and reflector. The images are taken from
a consistent set of positions to show the how the structural temperature distribution evolves over day and