From: NASA Blogs
Posted: Wednesday, July 2, 2008
I've been LOS for the last few days. LOS means loss of signal and in the lingo of Mission Control that means that you cannot talk with the astronauts because the radio signal is blocked. My LOS was caused by taking a couple of days off (personal business!! Or rather my wife's honey-do list!) and not having the Blog software set up on my home computer . . .
Anyway, this is a good day to tackle some of the comments and questions that folks have been posting, so here goes. I'll start with the easy ones first and work up to the harder ones.
Bob Mahoney had a question about posting comments to my blog. First of all Bob, I don't know why special characters would block out your posts but there may be some weird software thing there that I don't know about. Secondly, all comments to this blog are moderated (a NASA requirement since this is an official NASA blog) and the moderator is me. So if you sent in a comment and it didn't get posted, possibly it was because I found it offensive or off topic (not likely at least so far) or more likely because I was LOS (see above). Obviously, this blog is not really my principal work duty . . . .
Dave Hromanik asked if Gene Kranz was going to appear at the NASA exhibit at the Smithsonian Folk Life festival on that National Mall in Washington, DC. Dave, to the best of my ability to find out, the answer is no. Sorry, Gene would have provided great commentary. But he keeps a very full schedule for a retired guy and unless something changes he is not going to make this event. See him on the Discovery channel most Sunday evenings when they show that great series "When we left Earth"
Coleton B. Cooke asked why the Ulysses probe is about to quit sending information back to earth. Ulysses is a pretty deep space probe and uses radioisotope thermal generators to produce power. Small amounts of radioactive material are embedded in a device that captures the heat from the natural decay and converts that to electrical power. After 17 years the process of natural decay has resulted in heat/power levels that are not adequate to power the spacecraft. As the rocket propellant freezes, the spacecraft will loose attitude control and no longer be able to point the radio antenna at earth. Or even power the radio for that matter. Wish we could "refuel" the probe, but its kinda far away . . . .
Coleton also asked if the wagon tracks from the Oregon trail are really still there. Yes, in some places, they sure are. I have seen them (and walked in the ruts) in a couple of places. Check out this web page: http://geoimages.berkeley.edu/geoimages/starrs/RUTS.html Some things really do last for 160 or more years.
Kenneth asked if we could devise a plan to keep the last Shuttle attached to the International Space Station as a new room. Kenneth, there are a couple of reasons why this basically wouldn't work. First of all the shuttle is primarily water cooled. That is, we use water evaporated (sublimated really) into space to cool the electronics. Water is a precious commodity on the ISS and is mostly recycled. If we can't use the electronics on the shuttle then it is basically a dark cave that is going to get cold in a hurry after the lights go out. Secondly, the weight of the shuttle will cause attitude control problems for the ISS over the long term. Its OK for a short term docked mission, but over the long term the control system would have a hard time compensating for it. But the biggest reason is this: how do we get the guys that flew up on the shuttle back? Sending more Soyuzes just to do that is probably cost prohibitive. So, look for a Space Shuttle Orbiter at a museum near you after they retire in 2010.
Michael Mealing asked (in a round about way) what I thought about the various private efforts to fly into space? Frankly I am very excited about these efforts and wish the various groups the very best luck in their efforts. It is perfectly clear that for the long term exploitation of space, private enterprise has got to get involved in a big way. The problem to date is that there has not been a good business case for private flights into space. The space tourism industry may make this possible. The up-front capital costs to build the first system is still huge and skeptical financial investors have not signed on; just a few visionaries who are willing to take on a high-cost, high-risk development project. Once the first system flys and turns a profit, the whole business should grow quickly. Anyway, I hope it will grow. So GOOD LUCK to all those guys trying to get off the ground!
Ed Minchau wrote that it was "deceptive" of me to talk to children at the Smithsonian Folk Life Festival and lead them to believe that they would have a chance to fly into space. Ed, I certainly hope I wasn't deceptive. Obviously there are currently only a limited number of seats planned for rides into space. But see above -- I really do hope that private industry, perhaps aided by NASA through the Centennial Prizes or the COTS effort --- will take off and allow lots of folks to go to space within MY lifetime. Looking at the children, it is hard to say what might be possible in their lifetime. If we give them a dream to shoot for. Anyway, I made no promises that I couldn't keep and told them each and every one straight out that I wasn't handing out tickets but encouraging them to think about future careers in the space related jobs. Hurt my feelings here, Ed.
Robert wrote that "space exploration is not meaningful enough . . . but space utilization is . . . what if it were NASA's goal to deliver to earth by 2040 sufficient energy to . . . " (fill in the blank). Did you know that under President Carter, NASA was given the goal of developing fuel efficient automobiles? Our heart really wasn't in it, but we provided several technical improvements and build a roadmap to more efficient transportation which was handed over to the Department of Transportation, where it resides to this day. When I was in college, there was a lot of talk about Space Power Satellites -- unfortunately the business case did not close: that would have been the most expensive electricity put into the national grid. Times have changed and solar cells are cheaper and more efficient. But the transportation costs to build an SPS (or lunar based power station) are still . .. astronomical . . We need to get the transportation system up and working (and more economical) before we can talk about building power generating plants in space and maintain a straight face. I personally like the Helium 3 fusion power plant. Helium 3 is potentially the best fuel for a fusion power plant and Helium 3 is plentiful on the lunar surface. Unfortunately nobody has built a working fusion power plant yet, and we still have to get back to the moon to dig up the Helium 3 . . . .So, one step at a time Robert. Your idea is a good one, just the timeframe may be a bit longer. In fact, I am positive your idea is the ONLY good way to power the planet -- but in the long term.
Ticonderoga wrote "It is NOT the job of NASA to fly in space . . . it is to enable others to fly into space". To which I say amen. The better job we do in getting more people into space in a more economical manner, the better it will be for all the pursuits that we can imagine in space. So I think we are aligned in intention, maybe just the execution is different than what Ticonderoga would like to see.
I am about out of time today, so I close with one other comment that I really liked. Scott wrote "none of NASA's budget is spent in space . . . all of it is spent here on earth . . . to keep our technology competitive with that of other nations". Well said, Scott.
Keep those comments coming folks. Some of the ideas are really energizing and thought provoking!
// end //