>What are the guestimates on cost and time (apart from Space Island Group's) for modifying a Shuttle ET into an ET-Station and launching it in place of the Orbitter (with the necessary modifications to get it to final orbit). <br /><br />Realistic costs for modifying/redesigning the ET into a wet lab are in the 2-6 billion range if NASA did it. This would end up being a complete tank redesign with no guarantee of success. They've been dumping ETs in the ocean for 25 years, there is no indication they will ever orbit one, much less outfit it. Space Island Group is an 80's holdover, IMHO. They are producing cool graphics and not much else. If they really wanted to make space habitats on a large scale, they would be working with Bigelow, not trying to get NASA to do something they have so far refused. <br /><br />Side payload on a "shuttle-C" type vehicle probably has a max diameter of 5-6 meters. Sidemounted payloads are, however, part of the problem not the solution.<br /><br />ET space stations have a certain Apollo/hacker panache' to them, but are not realistic with how NASA operates. IOS has a design called "Neptune" that includes a wet-hab in the LOX tank for their tourists. Skylab was a wet lab, reusing large tankage for habitable space makes sense but is not something NASA is interested in. <br /><br />One thing for LEO stations is that the ET has a very large cross-section that will increase any ET-Station's reboost needs. <br /><br />Josh <div class="Discussion_UserSignature"> <div align="center"><em>We need a first generation of pioneers.</em><br /></div> </div>