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Landsat 8: different strokes for different folks

Ever since the launch of the latest Landsat series of satellites by NASA, Landsat 8 has been actively collecting 11 bands of imagery with fantastic clarity. Landsat 8 so far has been very successful and it will soon take over in popularity of Landsat 7 as the most popular Earth imaging satellite.

However one thing to note is that Landsat 8 has slightly different spectral wavelengths to its predecessor resulting in different combinations. For example, its been the common norm to simply choose bands 4, 3 and 2 in RGB channels to highlight vegetation in false colour (red); this has changed to 5, 4 and 3 in RGB. Its often hard to change ones routine. We’ve put together a quick cheat sheet comparing both Landsat 7 and Landsat 8 bands, and which band combinations are best suited to observing different surfaces.

Landsat 7 vs Landsat 8

Landsat 7 vs Landsat 8 band wavelengths

Furthermore, we’ve put together a quick combination matrix that summarizes the use of Landsat 8 bands in highlighting different surface types.

Landsat 8 band matrix highlighting the best combinations to use to showcase different surface types.

Landsat 8 band matrix highlighting the best combinations to use to showcase different surface types.

In conclusion, Landsat 8 is continues a terrific series of what is the earth’s longest running imaging system. The more imagery we process for our clients, particularly for those requiring geological or vegetation analysis, we get to truly appreciate how good of a job the folks at NASA have done. Keep it up girls and boys!

 

First Landsat 8 Images

The first images taken by NASA’s LDCM or Landsat 8 satellite have started coming through.

NASA has also updated their LDCM website with a lot of technical data about the satellite and its mission, including the below quote:

 “But the work is only beginning for validating the data quality and getting ready for normal mission operations. These images were processed using pre-launch settings, which must be checked and adjusted now that LDCM is in orbit to ensure that the data accurately measure the intensity of reflected and emitted light received by the instruments. The mission operations team also needs to ensure that each pixel is accurately located on Earth’s surface. LDCM’s normal operations are scheduled to begin in late May when the instruments have been calibrated and the spacecraft has been fully checked out. At that time, NASA will hand over control of the satellite to the USGS, which will operate the satellite throughout its planned five-year mission life. The satellite will be renamed Landsat 8, and data from OLI and TIRS will be processed and added to the Landsat Data Archive at the Earth Resources Observation and Science Center in South Dakota, where it will be distributed for free over the Internet.”

There’s more information at NASA’s LDCM site:

 http://www.nasa.gov/mission_pages/landsat/main/index.html

Scantherma_Perth_Landsat8

One of the first images taken by the Landsat Data Continuity Mission satellite. Image courtesy of NASA