To Europa, by Bush-Pilot

In retrospect, probably the single biggest flaw in the space shuttle concept was creating a spacecraft to carry crews and cargo at the same time. No other method of transportation typically works this way. Whether you're talking about aircraft, trains, ships or whatever, passenger vessels carry passengers and cargo vessels carry cargo. Yes, a large passenger vessel might incidentally take very small amounts of cargo, and once upon a time cargo ships might take a handful of passengers, but nobody was going to mistake a passenger vessel for a cargo vessel. Except, you know, Alaskan Airlines flights inside Alaska. NASA seems to be steering its SLS rocket in the direction of alternating flights between crews and very high-dollar cargoes, rather than trying to accommodate both in a single flight. It's a subtle but important next step in mainstreaming spaceflight into the transportation industry as a whole.

According to Chris Bergin at nasaspaceflight.com (probably the best free space blog in the world, and its attendant pay site L2 is without parallel) NASA has padded its newest internal manifest for SLS with flagship robotic missions to Mars and Europa, and single-launch space stations interspersed with Orion crewed missions, in order to boost the launch rate to at least one per year. Taking advantage of SLS's enormous speed for robotic missions to the outer solar system seems a very logical extension of this, and further integrates crewed and uncrewed space exploration into a single, more unified program. For deeper space exploration, the payload capacity to carry space telescopes which could dwarf the James Webb has interesting potential as well. This program is evolving into a deep-space workhorse, analogous to what the space shuttle was supposed to be for Low Earth Orbit. Interesting times.