SOFIA Stratospheric Observatory for Infrared Astronomy (1992) [Ames 



Research Center] . A 3.5-m telescope proposed to be flown on 

 a 747SP aircraft as a replacement for the very successful KAO 

 during the interval prior to SI RTF. Backend instrumentation 

 supplied by observers. Some performance specifications are given 

 in Appendix B. 



TABLE 2-2 



ESA Telescopes with Potential for U.S. Collaboration 

 ORBITAL 



ISO 



Infrared Space Observatory (1992). Approved mission. The 

 instrument complement has been selected on the basis of a 

 competitive AO, but implementation is not yet complete and 

 some modification may still be possible. The selected instrumen- 

 tation is detailed in Appendix B. 



FIRST 



Far Infrared Space Telescope (1995). One of the four corner- 

 stones of ESA's long-term plans for space missions. Mission not 

 yet approved and the telescope may turn into an interferometer. 

 Strawman instrument complement described in Appendix B. 



XMM X-ray Multiple Mission (1993-2004). A series of missions that 



form one of the cornerstones of ESA's long-term plans for space 

 missions. Intended to complement NASA's AXAF (which excels 

 at spatial resolution) by providing excellent spectral resolution 

 from soft to hard X-ray regime. No missions yet approved. 



COLUMBUS Space-Station-related modules. This label covers ESA efforts to 

 define which of their spacecraft and on-orbit experiments could 

 benefit from a human-tended station. 



2.2 Space Station 



The Space Station is now envisioned as an evolving facility, with the first 

 phase, called Block I, scheduled to be functioning during the mid- to late-1990s. 

 The exact configuration of the station and the experiments that will be included 

 in Block I have yet to be determined. The station configuration and its evolution 

 from Block I to Block II appear to be well defined, but decisions on science 

 issues have not been made; the summary that follows will require updating. 



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