The administrative and technical services of Earthnet, 
along with the user interface and product distribution 
facilities, are being implemented at the present time at 
ESRIN (Frascati, Italy). Ihe Earthnet catalogue is being 
computerised on the RECON system (3) and should become 
operational early in 1978. 
It is intended that image data will be provided by the 
facility in both hard copy and CCT formats. Digital enlarge- 
ment and various levels of correction will be performed on 
request. 
4. SPACELAB EXPERIMENTS 
There are two main and interrelated objectives associa- 
ted with any experimental earth observation programme using 
advanced sensing methods; these are 
- to understand the capabilities and limitations of the 
various sensor systems proposed and to develop measure- 
ment techniques that can be applied to the different 
application areas under investigation; 
- using the proven remote sensing instruments and methods 
derived above, conduct experiments in the earth obser- 
vation disciplines aimed either at purely scientific 
objectives or at perfecting measurement methods for 
later applications-oriented missions. 
Many of the key contributions that are required to 
achieve these two objectives will come from careful and 
exhaustive ground based and airborne measurement programmes. 
These measurements are, however, not enough in themselves to 
define and specify completely the later automatic satellite 
systems; an intermediate orbital phase will often be 
required using the flexibility and increased capabilities of 
manned space programmes such as Spacelab. The role of Space- 
lab in meeting these two objectives 1s illustrated in Fig. 4 
which shows how the manned space laboratory can act as a 
bridge between the initial ground and airborne measurements 
and the final systems based on long lifetime automatic 
satellites. 
Two remote sensing experiments are planned to be flown 
in the First Spacelab Payload (FSLP) presently scheduled for 
launch by the Shuttle in late 1980 or early 1981. These are 
- the Metric Camera (Expt. no 1 EA 033) 
- the Microwave Remote Sensing Experiment (Expt. no. 1 
EA 034). 
Both experiments are provided to the Agency by the 
Federal Republic of Germany as general instrumentation for 
the FSLP.