THEMIS detects thermal infrared energy emitted by the Martian surface at nine different wavelengths. Eight of these have wavelengths between 6 and 13 micrometers, an ideal region of the infrared spectrum to determine thermal energy patterns characteristic of silicate minerals. The ninth band is at 14.9 micrometers and is used to monitor the Martian atmosphere. The shortest infrared wavelength, at 6.78 micrometers, is measured twice in two bands to improve the signal-to-noise ratio. THEMIS is therefore a 10-band instrument that detects nine different wavelengths [https://doi.org/10.1023%2FB%3ASPAC.0000021008.16305.94].