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Question: Why are the shuttle computers only 128K, which is sixteen times less than I've got on my tabletop PC at home?

The reason for that is right at the root of some of the problems with the Space Program, and it's a problem that you can't get around, I think. The Shuttle was designed in the 1970s. Once you pick a design, you have to start testing the equipment and rating the equipment. Not only do you have to test and rate the hardware, you have to test and rate the software. So NASA started in—let's call it 1973 or 1974—developing the software for the Shuttle. Once you start developing the software, you've obviously got to start developing it on some platform. They used the computers that were available then. If you remember 1973, I still had a slide rule in my desk in 1973. So 128K was not a small computer in 1973.

The amount of testing that has to be done on the software has to follow literally every path. Not only in the breadboard stage, but in simulators, and then in the Shuttle itself. While it's sitting on the launch pad, we exercise every path through the software that we can. That literally takes years. Now, if in 1990 you say, "I've got an idea. Let's replace the computers." Then you have to rebuild the software. Once you've rebuilt the software, that means you've got to go through several years of testing.

There you are again in 1996 with 1989 computers. You're always going to be six to eight years, maybe more, behind in technology because of the very real requirements of testing, and the very real expense of redoing that testing once you've already done it.

Question: Do you think there will be a manned mission to Mars?

The President has said there will be. However, since we have no Government today, I guess you're not required to believe that.

NASA has put forward, and the President has endorsed, and Congress, to some extent, has endorsed the concept of the Space Exploration Initiative, which has said that we intend to explore the Moon first. We're going to go back to the Moon. We're going to build outposts and scientific stations on the Moon.

Then, once we've done that and we understand it, we're going to send people to Mars. There's no timetable on that yet. The money during the first years is very small, if anything. It hasn't made it through the congressional appropriations process. The Senate zeroed it out and the House put it back in. So, it's going to go to conference and it'll get some money, but not a lot this year. The money in the first couple of years is for technology development. The cost doesn't really ramp up for maybe five or six years. Once it does, as you would imagine, it's a little bit of a steep ramp.

So it's hard to answer your question definitively. It's certainly clear that some day people will go to Mars. The President has said that it's going to be us, among others, who are going to be going to Mars first. But, we're not to that point yet.

Question: What did we learn from LDEF, which is the Long Duration Exposure Facility? Will we be able to repair the Hubble Telescope and learn many of the things that it was advertised to teach us?

The Long Duration Exposure Facility, for those of you who weren't around when it was launched back in 1983, was supposed to be up for a couple of years and then retrieved by the Shuttle. It was designed