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Future Space Exploration

  1. Aug 20, 2006 #1
    A few weeks ago NASA announced it's next generation of rockets. Based on The APollo design it will take us to orbit, ,the space station,and even The Moon.

    My questions are, do we want to do this? This would be taking us backwards since it's based on APollo technology. Is it reusable? Will it splashdown liek in the old days?

    There will be one version for carrying people and another for cargo. Is this what we want. The Space Shuttle may have been more roomy in the cabin but it could definetly carry more in it's cargo bay. The Ares as I believe it's called has no room for cargo. SInce the SHuttle is going to be retired aa future sattlies and probes will have to be launched by rocket. The shuttle's carrying capabilitites are large is has lots of power and space for cargo. Can any rocket match that?

    We already had one foot in the future with aspacecraft that lands liek an aurplane. The next generation was supposed to takeoff like an airplane.
    I was talking to a lady at The Johnson SPace Center the other day and she even said that this desgin is supposed to take us to Mars.

    I always thought we would use nuclear rockets to get ot Mars since the are far more powerful,faster,and very effecient. You could take far more cargo and people in far less time. Ares is so small it would take years to do amission to Mars with that.

    What do ou think. Should we keep the shuttle? Go with the Ares design? Use nuclear rockets to go to Mars?
     
  2. jcsd
  3. Aug 20, 2006 #2
    NASA's space shuttle is over 20 years old, has been in service for over 20 years and has experienced two fatal catastrophes. This is not something NASA needs to continue with. Since the abandoned Apollo program, NASA has been reduced to low-earth-orbit shuttle missions, a lackluster (and expencive) space station and an overall lack of creativity to dig itself out.
    This moon mission will restore NASA's image amongst the public and propell itself to Mars. Of course, this is assuming that NASA does not piss this away by going to the moon, reducing itself back to low-earth-orbit missions and run the risk of execution.

    Truth be told, there is no competition this time around or perceived competition or any reason to do this that is not based on the collness factor. This has been done before, and the best reason NASA has for going back to the moon, is because an entire generation has never witnessed something so spectacular as a moon landing.
     
  4. Aug 20, 2006 #3
    NASA CEV, CLV, CaLV

    Hello Line,

    I would consider myself qualified to help answering some of these questions. But I will also divulge here and now that I am employed as a Guidance, Navigation, and Control engineer for one of the teams bidding for the NASA CEV (Crew Exploration Vehicle).
    It is not a step backwards just because we are going back to a conically-shaped crew vehicle. It just so happens that this is the easiest (read:safest) geometric body configuration for recovering a human crew back into Earth's atmosphere. A vehicle like the Shuttle only adds a degree of flexibility in where and when it can land because of its CROSS RANGE CAPABILITY. An airplane-like body such as the Shuttle gives a very high Lift/Drag ratio, and this gives a great capability for cross-range maneuvering.

    To answer one of your questions, the CEV will be able to splash-down in the ocean for an emergency recovery and landing. But the primary design goal is to recover the vehicle and land it on Terra Firma. This allows us to re-use the Crew Module over and over again. Up to 10 times, minimum.

    This makes a lot of sense, because you are going to spend a lot more $ to make a vehicle that carries a CREW than you will spend on a vehicle that does not carry human life. One will be expensive, one will be cheap, but they can both contain similar components and subsystems.

    ARES is defined as nothing more than a Launch Vehicle Configuration. The CLV (ARES-1) will be designed, built, and rated to carry humans into space on the CEV. The CaLV (Cargo Launch Vehicle) (ARES-5) will be designed, built, and rated to carry small and large cargo payloads into orbit.

    Yes. The CaLV (ARES-5) configuration will be able to carry more mass to orbit than its predecessor, the Saturn V.

    This is part of several misunderstandings about what design shape works best for different flight modes. There is no doubt that a symmetrical conical shape (capsule) is MUCH MUCH MUCH more reliable (and therefore safe) for a recovery vehicle. The Shuttle is nice because it lands like an airplane (more flexible), but it is also MUCH more risky because of the high temps and pressures of re-entry for a winged configuration.

    Again, you need to understand the differences in design optimization and safety for spacecraft and aircraft. They are different design problems.

    You are not thinking modularly. ARES-5 is a heavy launch vehicle (more mass to orbit than Saturn-V) that can put many pounds of unmanned mass into orbit. These will be pieces of a large spacecraft that can go to Mars. We can assemble the non-human pieces on-orbit. For example: We could make 3 ARES-5 launches with spacecraft engines and habitats to go to Mars. Then we just make ONE ARES-1 launch with a crew of 6 in the capsule. They mate-up with the spacecraft that was built on-orbit and off they go to Mars.

    Between the CEV, CLV, and CaLV we have a highly modular SYSTEMS ENGINEERING approach to spaceflight and space exploration. Now if you add to it the Commercial Orbit Transportation System (COTS) contrac that NASA has just awarded, you can see the beginning of a comprehensive, modular space access system.

    My own personal opinion is that it makes a lot of sense, if you are committed to build the space access "components" for at least 10-20 years. It is much cheaper to do it this way if we really are committed to doing it for the long haul. In doing so we will have built a myriad of different systems that can be merged, integrated, and interchanged with each other.

    Think of it like the early 1900s with automobiles. The greater the number of manufacturers we had putting product out there, the better the products became in getting the job done due to competition. And this is a very good analogy for how to think about what we are starting to do... In the early 1900s the technology was about automobiles and aircraft. By the end of the 1900s we had mastered the automobile and the aircraft, and we were starting to venture into space. Now in the 2000s we are striving to master (systematize) access to Space from Earth. We will be just as successful in this endeavor as we have been in our previous endeavors.

    So who wants to be the "Ford" and "Chevy" of Spacecraft? The market is wide open at this time. :biggrin:

    Rainman
     
  5. Aug 20, 2006 #4
  6. Aug 20, 2006 #5
    Now this has been pondered before and they decided assmbling a spacecraft in Space to go to Mars is impossible.

    It would be a possibility to assemble a heavy rocket on The Moona nd Launch it which is what this Mars initiative President Bush is pushing is all all about. I SAY NUCLEAR!!

    WHat alot of people don't know is that we were planned to go to Mars by The Early 80s. it was to use nuclear rockets but antinuke orginazations got on it because of the nuclear part so it got dropped.
     
  7. Aug 20, 2006 #6
    Uhm. I beg to differ with you, for the simple fact that none of my bretheren in aerospace engineering would brand something "impossible", especially something as trivial as this. It is certainly within the realm of possible and I challenge anyone to prove otherwise. The key is how affordable you can field such a system. Some solutions will be cheaper than others. That is why we do design trade studies.

    But I must say, I am a bit alarmed at how quickly you use the word "impossible". Surely that is a difficult concept to pin upon any technology.
    Nuclear propulsion certainly does make sense for certain mission functions, I will give you that. I fully support your view in this regard when it comes to "Orbit Transfer Stages" that would act as standardized impulse engines to transfer ships from Earth orbit to Lunar orbit, and from Earth orbit to the orbits of other planets. All of this is calculable and within the realm of a smartly-designed Orbit Transfer System.

    Rainman
     
  8. Aug 21, 2006 #7

    LURCH

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    I think that Lunar-based launch faciltities are the only practicle option for nuclear propulsion. If we tried to put nuclear fuel into Earth orbit the public outcry would be overwhelming. Launching a sattelite with small amounts of radioactive material caused enough protest, but a propulsion system would involve large amounts of weapons-grade fuel together with a detonator. People wouldn't stand for that wizzing right over their heads.

    OTOH, a refinement facility on the Moon could prduce all the weaps-grade nukes they want, and put it into Lunar orbit, and nobody would objcet. If there's an accident, let it vent; if there's a launch accident, let it fall. There's just nobody there to get hurt. Of course this would be a form of nuclear prolifferation, so there might be some protest about that.

    But the main problem would be cost. Rainman, have you seen any studies about the Lunar Launch Facility, and what the costs would be, and the savings f an Orion-type vehicle? I mean, if we used a nuke-powered vehicle and launched from the Moon, would we save or lose money compared with conventional chemicle rockets launched from Earth?
     
  9. Aug 21, 2006 #8
    WHat the danger with nuclea propulsion? Theyfuel won't detonate on it's on it will take someone in a controlroom to start a reaction. Besides it would hardly explode. It's a slow controled reaction. They're not gonna detonate all the fuel at once. Even if it crashed, nuclear material doesn't explode unless you fire neutrons at it. So setting fire or dropping it won't cause any danger. And it doesn't becoem radioactive until fired.
     
  10. Aug 22, 2006 #9

    LURCH

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    True, it wouldn't be likely to explode upon impact with the atmosphere or ground, but it's certainly not impossible.

    And the fuel is radioactive. It does not "become" radioactive after it is fired, it is deadly the moment the refinement processes complete. If it enters the atmosphere, burns up and becomes aerosolized, it could kill thousands. An unlikely scenario, but far too dangerous for most people to be willing to risk.
     
  11. Aug 22, 2006 #10
    Hello Lurch,
    What we must remember is that the moon is a "gravity well" just like earth. So there is really no savings at all to speak of launching from the moon. If one wished to use nuclear-powered engines, the most effective point to initiate their use would be the Earth-Moon Lagrangian point known as "L1". This is the point at which the Earth's and Moon's gravitational pulls are balanced out. This would be the lowest energy point at which to assemble a spacecraft made of modular, "reasonably launchable" pieces.

    In fact, in my early days on the CEV program (after NASA canceled the Orbital Space Plane in 2004) I worked on a team exploring and analyzing strategies for how to "intelligently" get to Mars while using the Moon as a place to "practice" long-term survival strategies in space. We came to the conclusion that all Mars missions should originate at L1, and that it would even make sense to have an unmanned "outpost" that would orbit the L1 point. This was an interesting time for me and my career, because you REALLY have to think differently in space. This is something that the average earthling is not trained to think about, but rather imagine that things in space work just like they do here on earth. They don't, and what is optimal here (straight-line or even great-circle routes) are far from optimal when considering orbital dynamics.

    Rainman
     
  12. Aug 23, 2006 #11

    LURCH

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    Thanks for that reply.
    Yeah, I was thinking about the Moon's gravity well, but it's a lot less than Earth's. And I know that construction in space can be more difficult than construction on the surface (even the Lunar surface). But you guys figured out the cost of descending into and then climbing back out of the Moon's well would be more expensive than the savings you'd get buy having ground under your feet during assembly, right? That must be largely effected buy the modular design and the relative ease of just "putting together" the pre-fab pieces, yes?

    But I was wondering (about nuclear propulsion). This method saves alot of transit time and nearly elliminates restrictions on launch weight. But the fuel should not be refined and then launched from Earth; that would be inviting disaster and sooner or later a launch failure would occur. The refinery would have to be spaceborn, and not in Earth orbit, either (or at least not LEO; maybe geostationary). The intial expense of putting such a facility into space would be emense, but the returns would be long-term, as it keeps producing fuel for vehicles that could be launched from the surface to the fueling station, and then onward to the Solar System. I just don't know if the benefits would ever outway the costs.

    Did your investigations include such a scenario (the fuel production facility being spaceborn), or was it just the Final Assembly station? Also; isn't L1 an inherently unstable (dynamically unstable, IIRC) position? How much fuel would be required to keep the station in place (say, per year, or whatever time period)?

    Gotta say it once again; I LOVE THIS PLACE!!!!
     
    Last edited: Aug 23, 2006
  13. Aug 23, 2006 #12
  14. Aug 23, 2006 #13

    LURCH

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    LOL! Speaking of nuclear propulsion, eh?!
     
  15. Aug 24, 2006 #14
    I'm getting pretty excited about this, I work for NASA in Houston on the CEV Flight Dynamics team and we are looking forward to welcoming the contractor on-board once the selection is made and I can't wait to really ramp things up. I've only worked on the team for about a year and a half now but we've made a lot of progress and I am excited about kicking this thing off officially. I've also seen the mission patch and it's pretty slick, I wish I could post it, but they were going to hold off on the naming announcment until the prime was announced and I think they are trying to hold back as much as possible to make the announcement more of a fanfare type event.

    LURCH to answer your question, yes the L1 point is dynamically unstable and would require some kind of station keeping by any spacecraft placed there.
     
  16. Aug 31, 2006 #15
    I Extend my CONGRATS to the LockMart Team!

    As a member of the losing team, I find the best words I could use are to modify a famous Apollo quote as I congratulate my worthy opponent:

    "Godspeed Lockheed-Martin!" (and NASA!) :smile:

    We will all be eagerly watching the progress.
    Rainman
     
  17. Aug 31, 2006 #16

    Astronuc

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    At the present time, nuclear propulsion is the lowest priority at NASA. The focus with nuclear is on the lunar surface power system.

    Otherwise the priorities are keeping Shuttle flying, ISS, and other exploratory and scientific programs, as well as various aeronautical programs.
     
  18. Sep 6, 2006 #17

    LURCH

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    Heh, yeah. I was just amused by the fact that thay named the new vehicle "Orion"; the same name as the nuclear propulsion program in the '60's.
     
  19. Sep 6, 2006 #18

    Astronuc

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    Orion was just one of many nuclear options under consideration.

    Orion was specifically the use of nuclear or thermonuclear explosions to propel a spacecraft.

    The main thrust in nuclear propulsion was Nuclear Thermal (NERVA/ROVER) systems. Research in electric propulsion was done parallel, and nuclear electric propulsion systems were also considered.
     
  20. Aug 29, 2007 #19

    Astronuc

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  21. Sep 16, 2007 #20
    In my opinion,the return to the Moon with apollo technology would be a better way to go in the next's years to Mars.The program of Apollo it was the best of the most NASA's programs.It was started before NASA became an organization.The rockets that the used to there was very safely and very useful exepted the Apollo 1 that was destroyed and the crew(Gus Grissom,Ed White,Chaffee) died.I think that the type of rocket that is the best to use is the type of Saturn-V.With Saturn-V Neil Armrstrong and Edwin ''Buzz'' Aldrin walked on the moon.Is the best choise.Maybe i have right maybe not.
     
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