beam array, a 90- by 20- by 12-cm box-like structure, was
mounted on top of the spacecraft sensory ring and was pointed in
the direction of the spacecraft's forward motion and tilted down
45 deg from the satellite antenna axis. The antenna beam scanned
the earth in 71 discrete steps for various angles extending up
to 35 deg on either side of the orbital plane. The deduced
brightness temperatures were expected to be accurate to within
3-5 deg K. Spatial resolution was 20 km in the cross-track
direction and 45 km in the direction parallel to the subpoint
track. For a more detailed description, see Section 5 of "The
Nimbus 6 User's Guide" (TRF B23261), available from NSSDC. The
ESMR performance was satisfactory until September 15, 1976, when
the horizontal channel output was zero due to a failure of the
Ferrite-Dicke switch. Selected ESMR images were presented in
"The Nimbus 6 Data Catalog" (TRF B26731), also available from
NSSDC.

Additional information available at
http://nssdc.gsfc.nasa.gov/database/MasterCatalog?sc=1975-052A&ex=3

[Summary provided by NASA]