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May I ask a silly question about upper rocket stage reuse? ... oh shoot, gonna do it anyway. Would it be possible to recover upper stages in orbit instead of on the ground? As far as I've understood, reusability of rocket first stages is possible because the first stage neither goes particularly high up, not particularly fast - relatively speaking, of course. Reusing the second stages would be harder since they go a lot faster and a lot higher - meaning that they would have to go through almost a complete orbital reentry and somehow survive intact, as their secondary function. Their primary function, of course, is pushing a payload from the high-and-fast-but-not-too-high-and-fast position of first stage separation, and (almost?) to the desired payload orbit (unless a third stage takes care of that). But say that the second stage is given extra orbital capabilities instead of re-entry/landing capabilities. Enough to enter stable LEO, and do some basic maneuvering. The same as what they do today, basically, but a little more. Then the second part of the plan, where the thread tags begin to come into play. It would involve a... let's call it a "butterfly net". A spacious but empty cargo spacecraft launched in advance, which does a rendezvous with the upper stage in orbit, loads it up and straps it in. This craft would be on a fairly long mission, loading up multiple upper stages from different launches, then re-entering and landing in a fashion similar to a space shuttle once it's full. Not necessarily on a runway, but smooth enough to allow its cargo to be reused. It would eliminate the requirement for the upper stage to be able to re-enter and land. It would "only" need to have orbital maneuverability instead. However, it's not very hard to see all the other problems it would introduce. Most prominently, the act of snagging, stowing, and securing a spacecraft inside another. And landing the damn thing while full of cargo, I presume. One might need human astronauts to do these tasks, which means craft with crew and EVA capabilities would have to operate alongside it. Maybe the upper stages could be stored temporarily on the "butterfly net"'s exterior and then properly stowed and secured in a single manned operation once it has reached capacity (say, 4-6 upper stages). Not sure if the landing could be done remotely, but that would be preferable, that way you wouldn't have to have crew compartments on the "butterfly net" itself. It would just have to be a big box that can be launched, maneuver in orbit, reenter, and land. I can't imagine it would be a profitable venture, since the development costs of such a program would probably be vastly more expensive than the dozens (let's say hundreds in the best case - still not enough) of upper stages it would allow the reuse of. Orbital maneuvering with a few upper rocket stages in its belly is probably not cheap when it comes to fuel either, and adding a rendezvous to every mission profile probably wouldn't be less expensive than just throwing the second stage away. Maybe second-order effects would recoup some of the costs, though. But would it be feasible, if not economically profitable? It would require the crew and EVA capabilities of the Space Shuttle, also roughly the same landing capability, albeit split into two different craft. Orbital rendezvouz would, optimistically, be on the same order of magnitude of complexity as docking with the ISS. Alternately, the "butterfly net" could instead be swapped for a manned orbital warehouse/workshop where upper stages would be collected, outfitted with heat shields, parachutes, legs, and/or what-have-you, then sent on their merry way back to the ground. Or just disassembled for parts, I suppose. Takes away the need to be able to land the big craft, at the cost of a permanent manned space operation, which we all of course know is not expensive at all. I feel like I'm not getting any closer to a viable/economically feasible solution here, so might as well hand the microphone over to you guys. What do you think of the concept?