Telescope

The TIM telescope is a reflecting telescope with a segmented, 2.0-meter diameter, carbon fiber primary mirror, as well as a fully carbon fiber secondary and support structure, with gold metallization of the reflecting surfaces to minimize the emissivity.

Spectrometer

To efficiently perform spectroscopy over the entire 240−420 μm band, we have two independent spectrometer modules: a short wavelength (SW) module covering 240−317 µm, and a long wavelength (LW) module covering 317 − 420 µm.

The two modules follow the same basic design; each consists of a plane diffraction grating mounted between concave collimating and camera mirrors in a Czerny- Turner configuration.

On September 23, 2024, from the NASA Columbia Scientific Ballooning Facility (CSBF) in Fort Sumner, New Mexico, TIM took to the sky for the first time on its engineering test flight. This was the most assembled the instrument had ever been before. The purpose of this campaign was to fully integrate and test the gondola and its subsystems, including: pointing motors, flight software, pointing sensors, telemetry system, ground station commanding, power subsystem (including a solar panel array), integration with NASA launch systems and payload communication network, and overall mechanical design.

At 7:26 am MDT, TIM took off for its 3 hour climb up to a float altitude of 120,000 ft (36.6 km). Once at float, various pointing and scanning tests were commanded from the ground, exercising motor control and communication with the reaction wheel, pivot shaft, and elevation axis motors. There were many sensors onboard, including star cameras, pinhole sun sensors, gyroscopes, inclinometers, and magnetometers. Their data were streamed to the ground and stored locally on the payload on hard drives secured inside steel pressure vessels for later recovery. Data from these sensors are combined in software to figure out where TIM is pointing, and to create a pointing solution on the sky.