Telemetry - (1) Radio signals from a spacecraft used to encode and transmit data to a ground station. (2) The science of measuring a quantity, transmitting the measured value to a distant station, and there, interpreting or recording the quantity measured.

Thematic data - Thematic data layers in a data set are layers of information that deal with a particular theme. These layers are typically related information that logically goes together.

Thermal infrared - Electromagnetic radiation with wavelengths between 3 and 25 micrometers.

TM--Thematic Mapper - "A Landsat multispectral scanner designed to acquire data to categorize the Earth's surface. Particular emphasis was placed on agricultural applications and identification of land use. The scanner continuously scans the surface of the Earth, simultaneously acquiring data in seven spectral channels. Overlaying two or more bands produces a false color image. The ground resolution of the six visible and shortwave bands of the Thematic Mapper is 30 meters, and the resolution of the thermal infrared band is 120 meters. Thematic mappers were flown on Landsat 4 and 5."