The Thematic Mapper is a nadir-viewing, seven-band multi-spectral scanning radiometer instrument, capable of providing low to medium-resolution imaging information of the Earth's surface. The first of the series was placed onboard Landsat 4 in 1982 and continued in operation until 1993. The Landsat 4 TM accompanied the MSS (Multispectral Scanner).

The TM data are scanned simultaneously in seven spectral bands. Band 6 scans thermal (heat) infrared radiation. Spectral and spatial characteristics of these bands are shown below:

Band no. 1
Spectral range: .450 to .520 micrometres Ground resolution: 30 m
Band no. 2
Spectral range: .520 to .600 micrometres Ground resolution: 30 m
Band no. 3
Spectral range: .630 to .690 micrometres Ground resolution: 30 m
Band no. 4
Spectral range: .775 to .900 micrometres Ground resolution: 30 m
Band no. 5
Spectral range: 1.550 to 1.750 micrometres Ground resolution: 30 m
Band no. 6
Spectral range: 10.40 to 12.50 micrometres Ground resolution: 120 m
Band no. 7
Spectral range: 2.080 to 2.350 micrometres Ground resolution: 30 m