Space station science officer Ed Lu sees a potential "silver lining" in the aftermath of the Columbia disaster, saying today the loss of the shuttle may prompt renewed debate about development of more modern follow-on vehicles.

Lu and Expedition 7 commander Yuri Malenchenko were launched to the international space station April 26 aboard a Russian Soyuz spacecraft. The station normally is staffed by a three-person crew but with the shuttle fleet grounded, not enough water is available for a full complement. Instead, Lu and Malenchenko are serving as on-orbit caretakers, carrying out a modest research schedule and keeping the station shipshape while NASA works to recover from the shuttle mishap.

In an interview with CBS Radio, Lu said today he and Malenchenko are briefed periodically on the progress of those efforts, "but obviously, we're not very close to the actual progress of the investigation."

Asked if he was concerned NASA might emerge from the investigation with an overly conservative approach to human spaceflight, Lu said "that might be a very good thing, especially after we're uncovering problems right now. But I guess we'll have to see how it plays out."

Does he have any concerns NASA might be forced to "fix things that aren't broken?"

"It's just as important to make sure you keep doing the stuff that you've been doing right - and there's a lot of things we have been doing right - and that you don't mess up those things in your efforts to fix the mistakes that were made," he said.

"Actually, I think one of the good things about this is it could push us towards other ways, other access to space, meaning different vehicles," he said. "And in the end, if you look way down the road, obviously the shuttle is not what we're going to fly very, very long term from now. I don't know how much longer we will continue to fly the shuttle. Certainly there are probably, given modern technology now, newer designs that we can come up with and I think people are working on that. And maybe there is a silver lining to all this."

On a lighter note, Lu demonstrated how one plays an electronic piano in the absence of gravity. As it turns out, one needs a seat belt and foot straps.

"It turned out to be a lot more difficult than you might think," he said. "It's actually set up on a work table, it's just Velcroed to the top of it, and underneath there's two foot restraints, things we can set up at various locations around the laboratory here.

"And it turns out when you start playing, just pressing on the keys starts to push you away from the piano and it's very hard to anchor yourself. Especially, we've got a pedal underneath here, when you press on that, that tends to make your body twist and you can only play for about 10 or 15 seconds before you start to twist out of position."

He reached down and pulled up a thin strap attached to the front of the piano.

"So what I've actually had to do, you can see this strap, I actually have to strap myself to the piano to keep myself where I want to be in front of the piano," Lu said. "And even with this, it's still a little bit hard, I haven't quite perfected it yet."

He then strapped in and played the opening bars of "Linus and Lucy," the familiar theme from "Charlie Brown" TV specials and for the record, his technique appeared to work just fine.

Lu said he and Malenchenko have had no problems adjusting to life in orbit over the past 55 days. Former station commander Kenneth Bowersox said before he departed that a two-man crew would face a different social dynamic aboard the outpost without a third astronaut to mediate disputes and provide variety.

But Malenchenko said today he and Lu are getting along just fine.

"Well, I had an experience for four months (aboard the Russian Mir space station), two men, and I don't see any difference psychologically here," he said through an interpreter. "We're getting along very well. Probably if there were three of us, we would get a long very well as well. And we take great pleasure in our work. We work a lot here, we conduct experiments and we have plenty of time to talk and get along."

As for the station's water supply, the bulk of which normally is delivered by space shuttles, Lu said simple conservation measures were in place and barring any major malfunctions, the station can be safely staffed by two-member crews indefinitely.

"It's going really well, we're managing to conserve water quite well," Lu said. "You can drink all you want, what you have to make sure you do is that all of your towels, things like that, you make sure you dry off before you toss them into the trash, our clothes after we work out and so on. Because that water evaporates into the air and we have a system that collects the moisture out of the air and then purifies it and that becomes our drinking water. So you have to be sure you don't throw any water away in the form of wet clothes, wet towels, things like that. Just doing that simple step allows you to save quite a bit of water.

"We have plenty of food on board, especially with this latest Progress (supply ship), we've got enough to last through until probably the middle of the next increment after us," he said. "We also have now plenty of water because there was a huge water tank and a whole bunch of smaller water containers within that Progress, which we've unloaded. So I think we're good for quite some time."

Asked if he had any message for the American public about the value of pressing ahead with work aboard the space station while recovering from the Columbia disaster, Lu said "spaceflight is important and I wouldn't be here, Yuri wouldn't be here if we didn't believe that."

"I think exploration in general is important and while this is a small step, I think this is a step that's necessary for when we do really head out into the solar system. I think that is our destiny someday.

"It's important that we look at these setbacks that we have, learn the lessons we need to learn from them, and move on. Because if you don't have that spirit, and that's a very unique spirit to Americans and Russians in particular, this spirit of moving on in adversity and exploration, then I think that is a bad sign, if you just say OK, we're packing up and we're going home."

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