I am doing a project with Landsat which needs to find out 2 Landsat images of the same area for different time, have both the same observation zenith and azimuth angles. But I can not find any information about satellite observation zenith or azimuth angle of Landsat images. Any one has an idea where I can find that information?
Satellite zenith angle
Images from Landsat 1 - 7 are always nadir.
In other words, their satellite zenith angle is close to 0°.
Likewise, the _MTL.txt you posted corresponds to a Landsat 5 image, and so is a nadir image.
Off-Nadir imagery has been introduced with Landsat 8.
Landsat 8 images have a field
NADIR_OFFNADIR in their _MTL.txt metadata. The
ROLL_ANGLE field indicates the corresponding satellite zenith angle. (See the Landsat Data Dictionary for a brief explanation of each metadata field.)
A typical nadir Landsat-8 OLI/TIRS scene would have metadata like:
NADIR_OFFNADIR = "NADIR"
ROLL_ANGLE = -0.001
I am not aware of a metadata field for satellite azimuth. You could either use the
CORNER_ X / Y coordinates (or latitude / longitude respectively) (inside the _MTL.txt file) to calculate its azimuth.
Alternatively, you could utilize the WRS (Worldwide Reference System) information (metadata fields
WRS_ROW; for landsat 4 onwards, it is sort of a grid indicating where the satellite is on its orbit). Have a look at the USGS page with has WRS specification documents and shapefile downloads, it is basically straightforward.
However, if you are comparing scenes from the same area, the satellite's azimuth angle is not subject to any change.
(Note that Landsat Metadata has changed a little bit as of August 2012.)