May 17, 2011  -- As NASA prepared to launch the Space Shuttle Endeavor on its last flight, NASA Administrator Charles Bolden spoke with ABC News about life after the shuttle. After a final shuttle launch this summer, the U.S. will be unable to launch its own astronauts into space, and will instead rely on the Russians to carry people to and from the International Space Station. This period, which is expected to last until the middle of the decade, is known as The Gap.

ABC NEWS: With the upcoming final two launches of Space Shuttle, one of the questions that a lot of people are asking about is The Gap -- the gap for the U.S. ability to put Americans into space on its own spacecraft. We knew this was coming. How did you approach the possibility of having to endure a significant gap?

BOLDEN: I think it was easy for me to approach it because as you said, everybody knew it was coming. The big hurdle for us was to get agreement on the part of all five partners, us included, that we should extend the International Space Station through 2020, because that is the anchor for all future exploration for us. Once we got everybody on board with that, we were a lot more comfortable.

ABC NEWS: How concerned are you about relying on our Russian partners for this interim period? What hurdles does that create?

BOLDEN: The primary hurdle it creates is that people will become comfortable with it and won't feel the urgency that we feel to bring back a U.S. domestic capability to get our own astronauts and our partner nation astronauts to the International Space Station and other Low Earth Orbit destinations. You know, we tend to be shortsighted and our memory is short. I don't want people to get comfortable that the International Space Station is still operating and we don't need an American capability. We must have American capability.

ABC NEWS: How have relations with the Russian partners been in terms of knowing that once the Shuttle is firmly retired that we can rely on them as we need to?

BOLDEN: The Russians have been very reliable partners throughout our history, and I always go back and tell people that we are where we are today because of two things. One was the willingness of the Russians at the very outset of the program to provide, if you will, the nucleus of what has now become the International Space Station. The first two elements were the Functional Cargo Block, a power module that maneuvered everything around, and then the brains for the Station, the Service Module, because we weren't quite ready to put our own Service Module and Crew Modules up yet.

The second time they came to the fore was in another contingency, and that was after the Columbia accident. We would not have had a capability to get our astronauts to the International Space Station and continue the development of the Station had it not been for that. But I go back again -- I don't want anyone to get comfortable with that partnership and reliance on them because it is critical that as quickly as we can, we facilitate the success of American entities to deliver our own people to space.

ABC NEWS: When you talk about American entities, can you tell me a little bit about how you see the division of labor between NASA and the private companies that are carrying most of the responsibilities of developing these spacecraft themselves?

BOLDEN: I always divide it into two things. One is access to space, access to Low Earth Orbit, and the other is exploration of space or exploration beyond Low Earth Orbit.

What will be significantly different from the way we've always done it before is that NASA will no longer procure vehicles and operate them for Low Earth Orbit activities. We are going to completely rely on our partners to do that work.

We'll still have oversight in terms of safety and engineering and the like, but we are not going to over-prescribe what they do and how they do it. They know that we want them to be able to carry humans and cargo to the International Space Station and other places, and we're just going to sit back and let them tell us when they need our help in determining how you do that.

We in turn are going to work with them hand-in-glove in the traditional sense in developing the exploration vehicles, so you will see that the way we operate our exploration beyond Low Earth Orbit will be more in line with the way that we have done Shuttle over the last 20 years and the way that we did the Mercury, Gemini, and Apollo programs, where NASA and the industry team work hand in hand. Industry really built the vehicles, but NASA played a significant role in the design [of them].

ABC NEWS: I'm sure you've heard the criticism from some corners that the Constellation program that was developed under the last administration had support from both parties of Congress -- that it wasn't broken, so why are we deviating from it? How do you answer those questions?

BOLDEN: I would counter initially that to say that Constellation wasn't broken is not accurate.

Constellation, if you look at where we were, it was a deep space exploration program that failed to get funding from the administration and Congress for many years, and my predecessor, Mike Griffin, found himself having to take money from NASA's science and aeronautics budgets, having to de-scope what Constellation was supposed to do. If you talk to anybody who is knowledgeable on where Constellation was at the time that President Obama made the decision to terminate the program, it was a poor lunar exploration enterprise at best, because we didn't have landers. We didn't have any way to provide the infrastructure once you got to the surface of the Moon, and in fact, when I say we didn't have landers, we didn't have a way to get astronauts from lunar orbit to the surface.

So that is not being critical of the people in the Constellation program. That is saying that the assets that were provided to us through the previous administration and the Congress were insufficient to carry out the vision, if you will.

ABC NEWS: How important is your job in persuading the American people that there's still an important role for NASA during this gap?

BOLDEN: Personally, I'm not important at all. The position of the Administrator is critical in being "the" chief spokesperson for the President and the President's vision in terms of exploration, and so if we're not telling that story very well, I'm not doing my part.

The Office of the Administrator plays a critical role in being the spokesperson for what the President has envisioned, and as they say, the President proposes and the Congress disposes. With the 2010 Authorization Act, it was an overwhelming bipartisan agreement on the part of Congress as to the elements of that Act, what we should be doing in terms of commercial spaceflight, exploration, science, aeronautics, and the President partnered with them when he signed that Act into law.

In the full year Continuing Resolution that is now our 2011 Appropriations Act for all intents and purposes, once again you saw hard-fought negotiations between representatives of the President and representatives of the leadership of Congress who came together and again reached a bipartisan agreement in the Congress that was signed into law by the President. So you can't ask for anything better than that, and that's where we are.

That's why I tell people I am very optimistic. Space exploration has a bright future. Human spaceflight has an incredibly bright future. You know, everything that we did last week down at the Kennedy Space Center in celebrating the 50th anniversary of Alan Shepard's first flight for an American into space, everything we did, and Russia about a month ago in celebrating the 50th anniversary of human spaceflight, every speaker at those events emphasized that they thought it was critical for all of us to be able 50 years from now to look back and see how we had built on that progress.

We're just at the beginning. Fifty years sounds like a long time, but we're in the fledgling stages of human exploration beyond Low Earth Orbit.

ABC NEWS: I really appreciate your willingness to talk with me today. Thank you so much.

BOLDEN: You know, I guess I'd close by saying [you] will hear our detractors say, "But where are you going?" The important thing is that the destinations haven't changed since the earliest times.

This President has said he wants us to go to asteroids, eventually to Mars, even back to the Moon as necessary to enable us to get to these distant destinations.

Humans have not ventured beyond the Moon yet, and it's only been one nation that's ever gone there. If you go back and read Jules Verne or you go back and read people who wrote and dreamed, even before we had the first airplane, people have always wanted to go to deep space, and that's what we're trying to do. That's what President Obama has asked us to do.

This interview was edited for length.

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