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Users can find out the number of archive entries for a given area, verify 
the quality of data relating in particular to cloud coverage, and employ 
aids such as quick-look image catalogues, microfiche and remote-access 
computerised catalogues, etc. 
Earthnet can also distribute data from the HCMM system that has ceased to 
operate. Furthermore, Earthnet provides the principal investigators with 
data from the European convair 580 experiment (SAR-type data), conducted 
jointly by ESA and the European Community, and distributes data from the 
DFVLR metric camera flown on the first Spacelab mission in December 1983. 
THE DATA DISSEMINATION SYSTEM 
Data is disseminated through the central Earthnet Programme Office (EPO) at 
Frascati, a network of National Points of Contact (NPOCs) in the ESA Member 
States or Associate Member Countries, and distribution centres outside the 
Member States. The EPO on the one hand, and NPOCs and the distribution 
centres on the other, play complementary roles in data dissemination. Only 
standard products are distributed by the EPO and then redistributed by the 
NPOCs or distribution centres; the latter can also provide special products 
and services such as : 
- interactive use of computer systems 
- data analysis and interpretation 
- discipline-oriented application packages that can include data other than 
that relating to remote-sensing in space 
- precision processed data 
Jointly with some National Points of Contact (NPOCs), Earthnet has also been 
involved in a fast data dissemination project, SPINE (Space Informatics 
Network Experiment), which was intended to provide users with rapid access 
to archives of large-scale remote-sensing data. Using ESA's Orbital Test 
Satellite (OTS), the facility has made possible active interrogation of a 
central data catalogue,transmission of digital data and on-line consultation 
of quick-look data. 
FUTURE MISSIONS AND DEVELOPMENT OF THE NETWORK 
Over the next few years Earthnet will aim at giving users of satellite 
remote-sensing techniques access to the products of future experimental 
missions most suited to meeting their research and evaluation needs, and at 
making preoperational products available to them rapidly and regularly, 
while maintaining the highest possible quality. 
A increasing effort is put in contributing to the missions and projects 
detailed below : 
- the ERS-1 (European Remote Sensing Satellite) and 
- the NOAA-AVHRR (Advanced Very High Resolution Radiometer) missions 
- the APOLLO fast remote sensing Data Distribution Network 
- the COLUMBUS space station, EURECA and polar platform. 
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