Summary 
It is useful to summarize the status of the various spacecraft and national pro- 
grams. This is given in the following table. 
SUMMARY OF EARTH RESOURCES SATELLITES 
(January 1983) 
Country Concept Design Build Operating 
USA MAPSAT MLA Landsat-D prime Landsat-3 
Space station LFC/MPESS Landsat-4 
OSTA—3 
SIR-B + LFC 
USSR Space station Meteor 
Salyut-7 
Cosmos series 
France SPOT-3 SPOT-1 
SPOT-4 SPOT-2 
European AERS . ERS-1 SPAS-01/MOMS 
Space Spacelab-D Spacelab-1 
Agency MC + MRSE 
Japan ERS-1 MOS-1 
Canada Radarsat 
Brazil Equatorial 
India IRS-1 Bhaskara 2 
Netherlands TERS 
PR China Chinasat 11 Chinasat 10 
Chinasat 12 
Conclusion 
It is evident that there is a great deal of near duplication in the various pro- 
posals for future Earth observation satellites. Minor differences in orbit 
parameters, number and limits of spectral bands, resolution, and swath widths re- 
sult from the perceptions of research scientists and engineers in the various 
agencies, and there are different priorities assigned to the use of space sensors 
for agriculture, mineral and energy exploration, environmental monitoring, and 
marine sciences. However, it is inordinately expensive to build and operate 
Space systems, and equally if not more expensive to process, disseminate, and 
apply the data which can be acquired. Scientists and managers from all countries 
involved in space activities realize that satellites are inherently international 
in operation. Compatibility and complementarity of space and ground systems was 
a major discussion topic at the Second United Nations Conference on the Exploration 
and Peaceful Uses of Outer Space which was held in Vienna, Austria in Summer 1982. 
Remote sensing from space is probably the most important source of information 
required for solving global resource management problems. Developing the tech- 
nical, administrative, and particularly the political ability to operate competent 
systems is the biggest challenge in the next decade.