National Aeronautics and Space Administration
NASA Space Science Data Coordinated Archive

There are several indexes of Viking Orbiter imagery available. Descriptions of each follows.

viking_image_index.txt (2.5M)

This file contains an index giving the image id, latitude, longitude, and pixel resolution for all Viking Orbiter images. The first few lines of the file are given below:

latitude: of center of image (degrees), + is north, - is south
longitude: of center of image (degrees west)
scaled pixel width: image center pixel width in km

 image id   latitude  longitude  scaled pixel width
----------  --------  ---------  ------------------
003A01       +20.13      37.35           0.045     
003A02       +19.63      37.19           0.045     
003A03       +20.71      36.23           0.046     
      

vikindexB_S.txt (1.2M)

This file contains the image id, latitude, longitude, and pixel resolution for the B and S images from the file above.

vikindexA.txt (1.2M)

This file contains the image id, latitude, longitude, and pixel resolution for the A images from the file above.

mars_gazetteer.txt (281K)

This file contains a list of IAU approved names of features on Mars and descriptions of the features and their locations. The first few lines of the file are given below:

Mars Gazetteer

Mars feature names and locations.
Explanations of columns are given at the end of this list.

Target  Search Feature            Feature Name                   Min.    Max.  Center   Min.    Max.   Center      Length       USGS      Name      Appr.  Feature                  Map      Description
 Body       Name                  (w/ diacritical marks)         Lat.    Lat.   Lat.    Long.   Long.   Long.       (km)         ID      Status     Date    Type              ref.  ID
MARS  ,ABALOS UNDAE              ,Abalos Undae               ,  81.00,  81.00,  81.00,  83.10,  83.10,  83.10,CR,  218.00,EU,RM,I1811 ,IAU-APPROVED,1988,UNDAE               ,  57,80090 ,Classical albedo feature at 72N, 70W
MARS  ,ABUS VALLIS               ,Abus Vallis                ,  -6.30,  -6.30,  -6.30, 147.50, 147.50, 147.50,CR,  129.00,EU,GB,I184  ,IAU-APPROVED,1985,VALLIS              ,  56,MC18SE,Classical name for Humber River in England
      
 
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