One of the Earth observing sensors introduced in the Landsat program. A Thematic Mapper (TM) was first placed aboard Landsat 4 (decommissioned in 2001), and one is still operational aboard Landsat 5 as of May 2007. TM sensors feature seven bands of image data (three in visible wavelengths, four in infrared) most of which have 30 meter resolution. Landsat 7 carries an enhanced TM sensor known as the Enhanced Thematic Mapper Plus (ETM+). NASA's web page on the Thematic Mapper lists sensor specifics.
