To clairify a bit on my purposely vague post, I would begin by saying that I've always been a strong advocate of an aggressive space program, and while I am not at all opposed to a manned missions, I think robotic vehicles are the best way to go for most missions, especially planetary exploration.

I don't think we're anyway near ready to send men to Mars, and even if we were, I'm not at all convinced that the Red (or Butterscotch) Planet will ever be a hospitable place for long-term human habitation or settlement. Conditions on Mars are extreme and severe to a degree that none of us can imagine.

As I've noted before, why anyone would want to abandon our beautiful home planet for a wretched place like Mars is completely beyond me.

Explore, yes; colonize, no way.

As it stands right now, our space tools need reinvention. It may be that the Columbia tragedy will turn out to be one of those quirky things that have nothing to do with the design shortcomings of the shuttle system, but I don't think anyone would argue that this vehicle is the best we can do.

Since working in space has turned out to be far more difficult than was forecast, it's obvious to me that we need specialized tools and vehicles for this kind of work. We've all seen the discussions underlining the impossibility of the shuttle crew making simple tile repairs or replacement while in orbit, or even making the determination if such repairs might be necessary.

Obviously, we've got a long way to go in this regard.

Beyond this, we need specialized launch vehicles - big, dumb, lifters for the non-critical (if there ever is such a thing) stuff, and completely reliable, reusable, economical manned vehicles which offer abort options during launch and re-entry.

My favorite candidate for the manned vehicle is an air-launch system using conventional, air-breathing, heavy-lift jet aircraft. The best existing (barely) aircraft for this mission is the Antonov An-225 Mriya, originally designed to transport the Buran, the Soviet-era copy of the shuttle.

Finally, back to the guy sitting peacefully on the banks of the Mercy, while everyone else is tearing around going from one natural splendor to the next, looking for some understanding of Yosemite, trying to take it all in.

Maybe he sees things that the rest miss, but at the end of the day, back around the campfire, you can be sure that no one will want to listen to him. After all, he just sat there quietly on the valley floor.

There are many stories of the Prodigal Son who roamed the world seeking enlightenment, only to return home and find that the answers he sought were there all along.

sp