<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I wonder if anyone is able to describe how many missions it would have taken to build the international space station using the Ares V versus using the Space Shuttle? <br /> Posted by therocketjohn</DIV></p><p>You could look at it this way: Skylab, America's first space station, had a usable livable volume of 368 cubic meters (that of a two-bedroom house). Currently, the ISS has a usable livable volume of 358 cubic meters.....almost the same. Consider that the ISS has required 27 Shuttle flights, 2 Proton flights, 1 Soyuz assembly flight, 31 Progress supply flights, 1 automated transfer vehicle flight, 28 shuttle-based assembly spacewalks, 90 ISS-based spacewalks, and over 745 hours of assembly time. Skylab required <span style="font-weight:bold" class="Apple-style-span">one</span> Saturn V launch and one repair mission to make it operational. </p><p>It would seem that launching one large space station on a heavy-lift booster would make more economic sense than assembling it piecemeal, and it probably does, assuming you're willing to risk putting "all your eggs in one basket". Obviously, you risk losing your entire space station if your booster fails, whereas the loss of one component of the ISS isn't an unmitigated disaster. But possibly the greatest benefit of the ISS is that we are learning how to build large structures in space, and that is very useful knowledge if we are going to someday expand the human presence in the solar system.</p> <div class="Discussion_UserSignature"> </div>