The availability of more than one transportation system offers a robustness that has great advantage over reliance on a single system. We would like an independent way of getting access to the International Space Station (ISS).

It's really an end-to-end space system, not just a vehicle.

The international nature of the thing is totally essential. We wouldn't have been able to build a space station ourselves.

Clipper could also support exploration of the Moon. The concept could even be aimed at going much further.

It gave us the opportunity of completely cleaning that up and replacing it rather than doing a botch up and keeping our fingers crossed.

We're desperately anxious to get Columbus up. Having 10 tons of hardware sitting around in Bremen, or even in Florida, doesn't do a lot for you.

It's like the station's arm, capable of walking from base point to base point.