Many of the things you tout as being "fixable" by man are really not. Remember Apollo 13 - the trajectory correction was accomplished by hand and not assisted by computer because the computer was powered down. Humans were on board and the correction was just barely adequate. The humans on board had no idea that they were on the wrong trajectory. They wouldn't have known either - until it was too late. A rocket motor that won't start probably can't be fixed in space. Depending on what's wrong, even a manual switch to ignite the motor would not work. Most things in critical phases of descent happen too fast for a human to react and fix the problem. Machines are much more adept at tasks like this. There are some things that a human could modify, like commands to shut things down. But, I suspect that at least half of encountered problems would result in death for the creature on board rather than successfully salvaging a critical critical situation. Contrast that with the overhead required to maintain life aboard a spacecraft. I don't know the exact numbers, but again, think of the Command Service Module on the Apollo missions. Most of that stuff was for the benefit of the riders. I don't think any of it was used for scientific instrumentation. For that matter, the Command Module served the same life sustaining function, as did the entire upper half of the Lunar Excursion Module. In spite of all of this, I am in favor of manned missions. I agree with Chuck that we are still in our infancy in this endeavor. When we started our lunar designs and expedition planning, we didn't even have integrated circuits. They and many other very useful technologies were invented for the space program. I fully expect that if we ever get our collective act together, technology will be developed to fill the voids. It was done in the past, and it is short sighted to think that we have reached the end of technological development. I expect humankind will visit other planets in our solar system. First of these will be Mars or an asteroid. At some future time we will have colonized several of them including the moon and Mars. Life will be different for these intrepid explorers. There will be a different set of risks than we have on earth, but they will be manageable. And we will be that much more enriched as a race. Our problem right now is that we are too concerned with the short term, and the "Me" attitude. We'll get over that, but it will take a while. Mankind has a rich future. It only take a bit of vision and cooperation to realize it. ________________________________ From: Patrick Wiggins <paw@wirelessbeehive.com> To: Utah Astronomy <utah-astronomy@mailman.xmission.com> Sent: Friday, March 2, 2012 2:45 AM Subject: Re: [Utah-astronomy] NASA video: We Are the Explorers On 01 Mar 2012, at 17:24, Dave Gary wrote:
As Egon Spengler said as he came out from under the secretary’s desk in “Ghostbusters”…’print is dead’, so too is manned space flight. To say the ISS is in space is stretching it. Until someone can come up with a propulsion system rivaling “warp drive” why should we bother? Successful robotic missions to Mars stand at about 50-50.
50-50 because there were not humans on board to improve the odds. An example being the Mars Polar Lander which crashed when the onboard computer "thought" the craft was on the ground and shut off the descent engines when it was still high in the Martian sky. Had a human been on board to monitor the engines real time that would not have happened. Or one of the otherwise successful Viking Landers whose seismometer did not work because someone back on Earth had forgotten to to remove a locking pin before flight. Had a human been on board to remove the pin that would not have happened. Or what about Mars Climate Orbiter? Someone back on Earth forgot the mission was using metric measures and inputted American units instead causing the craft to enter Mars orbit too low and it burned up. Had a human been on board and seen quite a ways out that the approach was going to be too steep that would not have happened. Or the Soviet's Phobos 1 which was on its way to Mars when someone back on Earth accidentally commanded the craft to shut down and the craft was lost. Had a human been on board to make sure the computer was not shut off that would not have happened. And even the recent Phobos-Grunt, lost in Earth orbit when the onboard computer failed to fire the engine that was to propel the craft out of Earth orbit and on to Mars. Had a human been on board to ignite the engine that would not have happened. Those are just a few examples. I'm sure there are more. Robotic exploration has it's very important place but no robot can do everything a human can. And, maybe just as important, no robot can be curious and wonder "What was that?". One of the current Mars rovers, following its programming, once drove right on past what later turned out to be a very interesting meteorite. Fortunately someone back on Earth later saw the meteorite in navigation images and wondered "What was that?" and had the rover team turn the rover around and go back for a better look. I really like what the rovers have accomplished, but one of the folks on the MER team said a while back that all of the wonderful stuff the rovers have done over the past many *years* could be accomplished (and dare I add "exceeded") by a single human geologist on a go cart in a couple of *weeks*.
Nobody in their right mind (well, I would, but my mind’s not right) would undertake a mission after being told, ‘Well, son, you’ve got a 50-50 chance of getting there. Gettin’ back, though, is an entirely different matter.’
When the early Earth explorers left port on their sailing ships they knew they had a small chance of returning but they went anyway. And when others left to settle new places on the planet many had no intention of ever returning. While I'd prefer to return alive I'm sure there would be no shortage of volunteers willing to make a one way trip to live out their lives on Mars. It's just that today NASA is so risk and PR adverse that they don't want to even consider one way trips or riskier odds. And that's why I'm glad to see private enterprise entering the space game. Those pioneers are willing to take the risks and possibly reap the big rewards.
Send the probes. Forget the men.
I hope you meant to say "humans". Otherwise I'll bet there are a number of "XX chromosomers" who might want to have a private talk with you out back. :) patrick Speaking for myself and not any agency for whom I occasionally volunteer. _______________________________________________ Utah-Astronomy mailing list http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Send messages to the list to Utah-Astronomy@mailman.xmission.com The Utah-Astronomy mailing list is not affiliated with any astronomy club. To unsubscribe go to: http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Then enter your email address in the space provided and click on "Unsubscribe or edit options".