Minimize TM & ETM+

To help users familiarise themselves with the Landsat TM and ETM+ instruments, and ESA's data products, the Landsat Products Description Document  is available online.

The TM and ETM+ menu to your right provides information concerning the SPPA activities for these instruments.

A brief description of the instrument, its operations and main mission highlights are available in the sections below:
 

 

Minimize TM Sensor Description

Landsat Thematic Mapper (TM) is a multispectral scanning radiometer operating in the visible and Infra-Red regions of the Electromagnetic Spectrum that was carried on board Landsat 4-5. TM is a whiskbroom instrument designed and built by SBRC (Santa Barbara Research Centre) of Hughes Aircraft Company in Goleta, CA. TM is regarded as a second generation imager for monitoring Earth's resources with considerably improved spectral and spatial resolutions over those of the MSS instrument. The TM sensors have provided nearly continuous coverage from July 1982 to June 2013.

 

More detailed information on the spacecraft and Operations statuses for Landsat 4 and 5 is available here.

 

Rotterdam, Netherlands Image credits: USGS/ESA

Landsat 5 TM scene over Rotterdam, Netherlands Image credits: USGS/ESA
Minimize ETM+ Sensor Description

The Landsat Enhanced Thematic Mapper Plus (ETM+) was introduced with Landsat 7 and was built by Raytheon SBRS (Santa Barbara Remote Sensing), Goleta, CA. ETM+ is an 8-band whiskbroom scanning radiometer consisting of:

  • A primary mirror that sweeps side-to-side (across-track) to produce forward and reverse image scans, and
  • A Scan Line Corrector (SLC) mirror assembly that sweeps forward-to-back to compensate for the forward motion of the spacecraft during integration time. The motion of these mirrors deviates from an ideal line profile, introducing along- and cross-track geometric distortions that require compensation.

The principal functional differences between the ETM+ and the former TM series are the addition of a 15 m resolution panchromatic band and two 8-bit "gain" ranges. The ETM+ adds a 60 m resolution thermal band, replacing the 120 m band on ETM/TM (band Number 6). ETM+ data therefore cover the visible, Near Infra-Red (NIR), shortwave, and Thermal Infra-Red (TIR) spectral bands of the electromagnetic spectrum.

 

More detailed information on the spacecraft and Operations status for Landsat 7 is available here.
 

Landsat 7 ETM+ scene over the Kangerdlugssuaq glacier, Greenland. Image credits: USGS/ESA