Landsat Thematic Mapper
Landsat satellites
- The first Landsat (or Earth Observation Satellite) launched in 1972. The main instrument on the early Landsats
1 to 5 was the MSS (Multi-spectral
scanner) with 4 or 5 bands and about 75 m pixel resolution; USGS now distributes
it with 60 m pixels. These landsat also had a
RBV system.
- Landsat 4, launched in 1982, was the first to carry the Thematic Mapper (TM).
It had a maximum resolution of 30 m, with 6 bands in the visible and near
infrared, and a thermal IR band with 120 m resolution.
The Landsat archive really starts with this satellite, and for most places
in the world you can get usable imagery starting in the early or mid 1980's.
The TM was designed as a backup, but when the MSS died and NASA saw how good
the TM was, they did not even try to bring back the MSS.
- Landsat 5, launched in 1984, provided data until 2013. This long life,
well beyond the design specification,
was the result of it experienceing no significant problems and the loss of Landsat 6 at launch, and the SLC failure of
Landsat 7 in 2003 which degraded Landsat 7 performance.
- Landsat 6 (which failed to reach orbit in 1993) and 7 (launched in 1999) added the Enhanced Thematic Mapper (ETM) which has a
panchromatic band with 15 m resolution. The thermal band has 60 m
resolution, but is now distributed with 30 m pixels to match the other
bands.
- Landsat 8 launched in 2013 and had a number of improvements: more bands,
better radiometric resolution.
- Landsat 9 launched in 2021 and the first data
arrived in early 2022. It has ever better radiometric
resolution than Landsat 8
The value of Landsat lies in:
- A long archive of imagery monitoring the earth, which is especially
valuable for creating land cover data.
- An intermediate scale, which despite the current
availability of sub meter satellite imagery, is still valuable
for many regional studies.
-
Landsat 7/8 bands
Landsat data
Finding scenes by
path/row
Landsat file
naming conventions
Landsat introductions on the web:
Converting to TOA radiance or reflectance
Last revision 2/22/2022