Thermal Emission Spectrometer
The Thermal Emission Spectrometer (TES) is a compact spectrometer that can detect infrared radiation emitted from objects. It can determine the mineralogy of rocks and soils from a distance by measuring their patterns of thermal radiation.
A view of hematite abundance at Opportunity's landing site created with data from TES. Each roughly circular spot represents a single observation by the instrument. The hematite abundance has been color-coded, with blue showing relatively no abundance to red showing about 20 percent abundance.
Each 'pixel' of a TES image is actually a complete, detailed infrared spectrum.
The infrared (thermal) part of the electromagnetic spectrum can penetrate dust coatings common to the Martian surface. These spectra are studied to determine the type of minerals and their abundances, scientists are particularly interested in spectra indicating minerals that were formed by the action of water, such as carbonates and clays.
A TES spectrum of the soil at Opportunity's landing site that shows the presence of grey hematite. The "W" shape on the right side of the spectrum is where the martian soil signature (yellow line) matches the laboratory signature for hematite (red line).
TES Spectral graph for calcium sulphate.
The TES will provide spectral data, which can be compared to samples in the Mission Control Database Library for identification.