All this said the ISS would be a great candidate for interplanetary travel. Although it might look a little ungainly, in the vacuum of space there’s little concern for aerodynamics (besides, for a station orbiting at a speed of 17,000 miles/hr, its shape is hardly holding it back!). It’s a tried and tested space-worthy candidate. Plus, the Constellation Program would fit right in. Perhaps the Orion module could be integrated into the station, and the engines from the powerful Ares rocket could be attached for propulsion. If something a little gentler is required, ion propulsion engines are becoming more and more sophisticated.