enterprise was built ruggedly with construction because they didn't understand the loads going to and from space yet. after challenger was lost nasa considered upgrading it to space capability but they felt a lighter, newer shuttle, turned out to be endeavour would be a better bet for them. jenna: tom, we last week were talking about spacex, the new private venture to get, a rocket into space. i was going to use the term shuttle but really more of a rocket to the international space station up there. as you see kind of the space program evolve and think about what's ahead as well i'm just curious how you see these two news items together? >> well it is good news that last week spacex and its dragon capsule were successful in their run to the station as these shuttles go to museums. we can see perhaps a glimmer how nasa can reopen the supply line to the space station and eventually in five years fly astronauts. i would sure like to see that process accelerated and have these commercial ships in service sooner than five