I Love Learning Something New - Again

Well, I'm back from the conference and I think it went well. I think my own paper was well received and I saw a number of other presentations that were very nice or thought-provoking, particularly one that used lessons learned from a rather tragic sledging expedition in Antarctica. It might seem a stretch, to compare them, but I thought he had excellent points. When everything you need to survive has to be brought with you, when you might be stranded or cut off from your home base, you need to be prepared and think it through. Lessons learned from this I thought quite applicable to Moon or Mars EVA expeditions and missions.

Another interesting presentation was on EDDE, a proposed debris cleaning program for Low Earth Orbit. Now, I've been pretty skeptical that cleaning out the debris is a practical notion, but, I have to say, this idea was intriguing to me. Using a tethering system to gain energy as well as change altitude/inclination very quickly without propulsion - thanks to the electromagnetic field around the Earth (and I find that cool beans). It's not science fiction; tethers have been used several times in the past with considerable success.

According to the presentation, they could change hundreds of km a day in altitude, quite a bit in inclination and, theoretically, clean out all the cataloged debris up to an altitude of 2000 km in less than seven years with just twelve 100 kg units. Units could deorbit themselves or stay as policemen. Now, they claimed they didn't have to worry about uncataloged debris (I'm less sanguin about that) though I agree they could avoid the cataloged stuff. And I'd want more than a power point presentation before I was sold on the idea, but, it seemed like a fine idea.

Although all the small stuff doesn't get cleaned out this way, you limit the generation of more debris by taking out the big stuff. The smallest stuff is the most readily cleaned out by natural processes. They bring the stuff down to 330 km (pretty much below anywhere dangerous) and were natural atmospheric friction will bring it down in weeks instead of decades. As the electromagnetic field at geostationary is not strong enough to use this there, it's limited to LEO, but that is where many of our valuable assets are.

Even if it didn't completely solve the problem, if effective, it could make a real difference.

They have an animation of this that's well worth watching here. If it doesn't work, the link above (EDDE) has it there as well.

Read more...

Risks

There's a risk in my business if you spend too many years in safety or any critical profession (and, by critical, I mean looking over other people's work for flaws or problems). After a while, all you see with something is what's wrong with it. Where is could be safer or faster or more effective, the failings you found the hard way, the limitations, the dangers. Sometimes, it spills into your real life and you find yourself obsessing about what isn't there, what isn't working, what wasn't good enough. I have to constantly watch for it and I still fail quite frequently. I suspect I'm not easy to live with.

But I believe we're a necessary evil, as it were. Gil Stern said, "Both optimists and pessimists contribute to our society. The optimist invents the airplane and the pessimist the parachute." At NASA and, in fact, any organization where they strive to push the envelope and do what is unaccountably difficult, where doing the impossible is just one of the balls one has to juggle, nothing can happen without the dreamers, the ones who refuse to believe it's impossible, who stride forward undaunted no matter what the challenge.

That can be very very good. We would never have walked on the moon or driven robots on Mars without such dreamers and genius. The world was changed by the people who did these great things, who challenged the emptiness around our world in ways most people don't appreciate in the slightest.

But those accomplishments were not without price and many lost or nearly lost their lives to teach the rest of us hard lessons to carry forward to the next step. And it's times like these, when the old guard, who first conquered aspects of space-faring, are almost gone among us and all are left are those who have Shuttled to and fro to low earth orbit for the last two decades. They have accomplishments but they are incremental, tapping the opportunities in what is, space-wise, our own backyard. No new ships have been designed for man by either Russia or the US in decades.

That doesn't mean we shouldn't try—perish the thought—only that we are at our most vulnerable when it comes for forgetting the lessons of the past, the times we got lucky (and the over-designing that forged that luck) and the times we didn't.

That's what my paper is all about that I'll be presenting this week at the International Association for the Advancement of Space Safety Conference.

That also means I may not be back here until the weekend. Have a good one.

Read more...