NASA Selects Contractor for First Prometheus Mission to Jupiter

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mrmorris

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<font color="yellow">His objections about entering a polar orbit at Jupiter are not credible as stated. </font><br /><br /><font color="orange">Yeah, fortunately we have a very fine example of a probe that is going to enter a polar orbit eventually, out at Saturn. Cassini has been captured in Saturn's orbital plane, and over the next few years they'll be using Titan gravity assists to swing it into all sorts of orbits, including polar."</font><br /><br />Two things.<br /><br />1. My objections were to arriving at Jupiter and immediately entering a polar orbit as sm indicated was possible via inner-system maneuvers. I did <b>not</b> imply that it was impossible to arrive at Jupiter and spend the next several years using gravity assists from the various moons to alter the orbit. In any event, this method isn't reasonable for JIMO because it will be orbiting the moons, rather than the planet.<br /><br />2. Saturn's axial inclination is 22.4 degrees from the plane of the eliptic versus 3 degrees for Jupiter. This makes polar orbits around Saturn <b>much</b> more attainable. Cassini's orbit about Saturn was already inclined by ~22 degrees to the poles upon capture.<br />
 
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spacechump

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<i>...a parabolic concentrator mirror will not be able to focus to the same or nearly the same intensity and temperature as distance from the Sun increases. This is simply not true! ... the smaller apparent size of the Sun at Jupiter is such that the intensity at the focus remains the same <br /><br />Sorry, no. Your reflector is a fixed size? Then at Jupiter, it will collect and focus 25 times less solar energy than at Earth. Are you trying to say that we could focus to a smaller point at jupiter, because of the sun's apparent size? This has so little impact that I can't imagine you are serious. <br /><br />and the way I said that was that the inverse square law works both ways. Physics not opinion says you are wrong. <br /><br />Maybe if you drew a diagram to explain how the inverse square law even remotely supports your assertion? <br /></i><br /><br />In fact the law is working <i>against</i> his design. A fixed concentrator will receive less raditation (by which I mostly mean light but also whatever else the sun throws off) coverage per square inch as it travels from the earth to beyond. You'd have to compensate by changing the focus of your concentrator to try to concentrate. But that only help to focus what energy you receive. It does nothing to magically amplify it. Thus you're adding more complexity to the design overall by adding a mechanical solution to the mix. That is unless you can change the shape with reactance material.
 
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bobvanx

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<font color="yellow">Two things.</font><br /><br />yep!<br /><br />(BTW, were you intentionally modeling how to clarify a statement? I could evaluate your earlier posts and understand that you were were discussing polar orbit capture on insertion. But you elaborated clearly, and then you picked up the new data about Cassini and used it to support your assertion about O.M. in and out of the plane of the ecliptic. Impressive. If I wore a hat, I'd tip it!)
 
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mrmorris

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<font color="yellow">"BTW, were you intentionally modeling how to clarify a statement?"</font><br /><br />Modelling -- no. Just clarifying. I wasn't being completely clear in my earlier posts because sm kept referring to 'initial' orbit and I kept saying 'final' orbit. I was thinking 'when it finally gets to the point of orbiting around Jupiter', but I should have been saying 'initial'. At any rate -- I was fairly sure you had simply failed to understand my earlier posts rather than adamantly refusing to understand them. Not that anyone here would be doing something like that, of course.
 
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SteveMick

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Could you offer please one example of an objection I have ignored or not processed? I'll be happy to answer.<br /><br /> As for the nature of the focus of a solar concentrator it is true that the focus getting smaller (apparent size since the Sun forms an image at the focus) as distance increases does keep the intensity of the focus and therefore its temperature constant. Assertions to the contrary lack common sense.<br /> Secondly, mmorris et al need to drop the petty insults and realize the foolishness of saying that entering Jupiter orbit that is inclined or even polar is not possible. There does have to be energy added at perihelion but it presents no problem. Generally someone who is good at celestial mechanics would answer with math instead of assertions.<br /> By the way, do you guys really beleive that the JIMO power supply system as currently designed is the best that it could be? Do you think any improvement is possible? For instance, why not have a particle bed reactor cooled by a gas(helium?) operating at a high temperature. Higher operating temps. would mean a smaller, lighter radiator and the possibility of operation in a thermal propulsion mode via a gas to gas heat exchanger. Hydrogen propellent could be heated by the helium and exhausted to produce thrust so that the time to escape from LEO would be greatly reduced.<br /> I find it worrisome that there seems to be a blind acceptance of whatever is proposed even when the absurd situation of a submarine reactor company designing one for a spacecraft results in a bloated design. Do you guys have any ideas yourselves or is criticism of other's ideas your only specialty?<br />Steve
 
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SteveMick

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"Last point for you to consider: designing orbits takes alot of resources ($$) until such day as we have a BOINC type solution. It's already been pointed out to you that your solar craft is going to be unstable in at least two axes, which you ignored, so that adds more difficulty to designing its orbit. "<br /><br /> Sorry I missed the point about the solar craft being unstable - but that just seemed so obviously irrelevant that it doesn't seem credible. Any spacecraft, solar included must have the ability to be stable and gyros and thrusters and moters can work to stabilize even the much more massive JIMO. Perhaps I'm just not understanding the problem so please elaborate.<br />"...a parabolic concentrator mirror will not be able to focus to the same or nearly the same intensity and temperature as distance from the Sun increases. This is simply not true! ... the smaller apparent size of the Sun at Jupiter is such that the intensity at the focus remains the same <br /><br />Sorry, no. Your reflector is a fixed size? Then at Jupiter, it will collect and focus 25 times less solar energy than at Earth. Are you trying to say that we could focus to a smaller point at jupiter, because of the sun's apparent size? This has so little impact that I can't imagine you are serious. "<br /> That last part must be somewhat of an embarrasment to you. The "little impact" the smaller IMAGE size is only to keep intensity constant (inverse square law) which is exactly what I was asserting as possible. You and the others are simply ignoring physics.<br />"The tone of the discussion has taken a less than ideal tone as each objection has been answered with logical argument backed up with what math I can manage so I challenge both Yurkin and bobvanx to keep the "I'll just take my bat and ball and go home" type remarks to themselves and continue to discuss technical issues <br /><br />Perhaps you can read that comment again, and strive to understand that we're tired of throwing the ball to you only
 
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bobvanx

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stevemick,<br /><br />I'd like to honor your obviously heartfelt request to set you straight, but at this point I feel like there aren't enough hours in the day. You're still doing it, that is, failing to process the facts that we've used, and honestly, if we were in business together, or in-laws, or if there were some human-connective reason I needed to keeping beating my head against the brick wall, I would spend the time. People are worth it, and you are, too.<br /><br />Promise me this: if you are ever in a burning building, when the firefighters come to rescue you, don't argue about how you don't need to leave because the frame of the building is steel, and it's just the furniture that's on fire, ok? Just go with it, and get out.
 
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halman

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bobvanx,<br /><br />I will NOT be wrong, and I am SURE that you are.<br /><br />When you champion an unappreciated way of thinking, you must learn to ignore distractions, like facts, economics, political realities, and the hope of ever having friends.<br /><br />This discussion has convinced me that much more research into methods of converting sunlight into usable energy are needed. It has not convinced me that we should stop the development of the Jupiter Icy Moons Observatory (or whatever the O stands for,) until that research has been performed. Of course, some people are convinced that no further research is needed, and that JIMO would be the perfect way of demonstrating that.<br /><br />Is the probe about proving methods of providing energy? I thought that its intent was to thoroughly explore some of the Moons of Jupiter. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>
 
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SteveMick

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mmorris writes:<br />"Huh? Radar is one of the highest powered instruments that will likely be onboard. The only reason I can think that you'd make a statement that it wouldn't matter whether it were made in shadow or not is if you're confusing the 'function' of radar with its power requirements. Visible light is not required and radar can indeed function in total darkness -- but only if it has the power to do so. <br /><br />This is one of the primary reasons why it will be of use in imaging the darksides of the three moons in question. All three moons are tidally locked because of their proximity to Jupiter. Since they always present the same face to Jupiter -- their dark side revolves around the surface at the same rate as their orbital period or 3.1, 7.2, and 16.7 days for Europa, Ganymede and Callisto respectively. A probe orbiting these moons is going to have to produce science while periodically being in the shadow of the moons, and Jupiter -- while the 'sunward side' of the moons slowly creeps around. I repeat once again -- a probe that has full power despite the amount of sunlight it's currently receiving makes for a much more productive mission. "<br /><br /> My point was that there is no part of any moon that could not be imaged by radar powered by solar energy. I agree that constant power is better all things being equal, but the effect of inconstant full power would only be to delay some observations at worst. There is nothing special about imaging a moon with radar while it is in shadow, so there is nothing lost scientifically by waiting untill sunlight is available, just time. Time is important, but if you're content to wait ten extra years to launch a nuclear probe as opposed to a solar one, the practical effect is that the solar probe will have made many more observations before JIMO could even get there and with equal funding there would be dozens of solar powered probes vs. one JIMO.<br />"The orbits of all the planets in the solar system are largely in
 
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spacechump

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<i>and the intensity of an imaged focus remaining constant with distance from the Sun I have been correct lest I be accused of just repeating my assertions as you so unkindly and inaccurately state.</i><br /><br />No...no...no. Only if you keep the focus as tight as you can and you'd have to adjust the concentrator for this. And even then, as the sun act more and more like a point source, you receive a lower and lower radiation flux as you move out. You can only concentrate what solar radiation is hitting your concentrator perpendicularly. And as the apparent image of the sun decrease so does the overall flux your concentator receives. Therefore you need to make the focus tighter and tighter until it no longer matters...there's just too little to work with. I'm not saying solar can't be used that far but to have a fixed concentrator size without active compensation while moving toward the target is absurd .
 
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bobvanx

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<font color="yellow">you must learn to ignore distractions, like facts, economics, political realities, and the hope of ever having friends.</font><br /><br />ROFL. Thanks, halman.<br /><br />Here, Steve, I did some of your homework for you:<br /><br />Power Antenna<br /><br /><font color="yellow">Is the probe about proving methods of providing energy? I thought that its intent was to thoroughly explore some of the Moons of Jupiter.</font><br /><br />Like any good expenditure, it has many goals. The primary one that I care about is the develpment and demonstration of a high-power, compact, always-on energy source for space applications. Having the Navy involved, with their proven safety record, is very thrilling to me.<br /><br />Space Nuclear Power is an enabling technology for human colonization. But don't tell anyone yet. Colonization is too scary a concept to be addressed at this time. Let's just get our power source, and then commercialize it, and build quietly towards people on Mars.<br /><br />Science at Jupiter is a wonderful <b>application</b> for this technology. So too, will be powerful rovers on Mars, rovers in the shadow craters at Luna's poles, cryobots to explore Europa's probable ocean, and so on.<br /><br />+++++<br /><br />Space Solar Power, on the other hand, is a wonderful technology to release us from our dependance on fossil fuels and the environmental load they carry.<br /><br />We absolutely need both, an opinion I've posted before. To move solar forward, we need to have people intelligently expounding on its assets. I realize now, that's why I'm struggling to help Steve understand his errors. Because I love Solar. I want to see it developed. And I feel that misconceptions about the true capability of Solar get in the way of moving forward on that goal.
 
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mrmorris

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<br /><font color="yellow">"Secondly, mmorris et al need to drop the petty insults and realize the foolishness of saying that entering Jupiter orbit that is inclined or even polar is not possible. There does have to be energy added at perihelion but it presents no problem. Generally someone who is good at celestial mechanics would answer with math instead of assertions."</font><br /><br />You haven't dropped an equation into a single one of your references about this 'perihelion' maneuver you keep referring to. By contrast, I have detailed how all of the vectors from Earth to an equatorial orbit about Jupiter and the orbits of the three moons in question all lie in the same plane.<br /><br /><font color="yellow">"It is of course true that the probe will follow the plane of the ecliptic untill it reaches perihelion. At that point it would aim its thrust vector appropriately and apply thrust to change the plane of its solar orbit and head to Jupiter. Are you saying that this is not possible? <br />If so, you live in the alternate universe. "</font><br /><br />The path that the probe needs to take from Venus to Jupiter is along the plane of the elliptic. If you somehow slingshot the probe above or below that plane using Venus' gravity, it will never make it to Jupiter. It will instead simply continue further and further above (or below) the plane of the eliptic as it gets further from the sun until by the time it's at the same horizontal distance from the sun as Jupiter, it will be so far above (or below) that Jupiter's gravity will be unable to affect it at all. If you fling the probe above the plan at Venus -- how are you getting it back?<br /><br /><br /><font color="orange">"Even Ulysses had no significant polar vector prior to its slingshot around Jupiter. It was sent toward Jupiter, timed to arrive at a point in space just in front and below the planet. As Jupiter closed on the probe, it 'fell' toward Jupiter, curving its flight path up above the pl</font>
 
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bobvanx

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<font color="yellow">but that just seemed so obviously irrelevant</font><br /><br />I debated with myself about continuing my efforts to enlighten you about how physics works, and how logic functions. There are parts that directly apply to how well you can explain what you are trying to accomplish with your solar power craft.<br /><br />But when you take a legitimate, measurable, testable observation, and dismiss it as obviously irrelevant, I realize that I could provide you with any amount of helpful critique to move the engineering of your idea forward, and it'll all be dismissed because it doesn't fit the fantasy craft you've built in your head. You didn't even spend the time to work it out, to show me some solution to stabilizing an unstable vehicle in a dynamic evironment. You just tossed it.<br /><br />And while you keep telling us that it's rude, or unpleasant, or whatever, to be knocking your idea, you're missing the point that we aren't knocking you. We keep showing you the tools you need to have a discussion about an engineering problem, and you keep using the tools of myth, fantasy, and persuasion.<br /><br />So since you prove to me that on any single component, you refuse to look at it realistically, you dissuade me from putting any effort in to showing you the engineering limitations on all the other components.
 
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najab

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<blockquote><font class="small">In reply to:</font><hr /><p>As for the nature of the focus of a solar concentrator it is true that the focus getting smaller (apparent size since the Sun forms an image at the focus) as distance increases does keep the intensity of the focus and therefore its temperature constant. Assertions to the contrary lack common sense. <p><hr /></p></p></blockquote>A focus is a point. It doesn't get any smaller or larger due to distance from the object - it remains a point.<blockquote><font class="small">In reply to:</font><hr /><p>There does have to be energy added at perihelion but it presents no problem. Generally someone who is good at celestial mechanics would answer with math instead of assertions.<p><hr /></p></p></blockquote>There are forum members who could provide the math, but first you would have to demonstrate that you would understand it. The fact that you insist that plane changes are easiest at perihelion indicates that you have no understanding of orbital mechanics.<p>Are you familiar with Kepler's laws? His Second Law shows that orbiting bodies sweep out equal area in equal time. What this means is that at perihelion the probe is moving with <b>maximum velocity</b> - which means that rotating the velocity vector requires maximum work. It is actually easiest to effect plane changes at aphelion.<blockquote><font class="small">In reply to:</font><hr /><p>By the way, do you guys really beleive that the JIMO power supply system as currently designed is the best that it could be? Do you think any improvement is possible? For instance, why not have a particle bed reactor cooled by a gas(helium?) operating at a high temperature. Higher operating temps. would mean a smaller, lighter radiator and the possibility of operation in a thermal propulsion mode via a gas to gas heat exchanger. Hydrogen propellent could be heated by the helium and exhausted to produce thrust so that the time to escape from LEO would be greatly reduced. <p><hr /></p></p></blockquote>Nope, not by a</p>
 
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yurkin

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I think steve is confusing a certain point in of the inverse square rule concerning light. It states that the total intensity of light does not change with respect to its distance from the source. For instance, if you were to sum up the total energy in watts from the sun at one AU it would be the same as that at 5 AU. Of course you’d have to factor out the shadows cast by planets and such. But total energy is different then specific energy with respect to area. You see at 5AU the sphere that the total light hits is 5^2 times the sphere that that same light hits at 1AU. It doesn’t drop in total intensity it just has to cover a much larger area. And the surface area of a sphere is the 4*3.14*radius^2, this is the physical definition that explains why the inverse square law is the way it is. As best I can describe it.<br /><br />But steve brought up an interesting problem that I had neglected to consider. That is the columniation point of the concentrator is going to change as the craft gets further from the sun. This wouldn’t be as big a problem with a reactor, because closer to the sun you would want it outside columniation. Since that intensity of heat may damage the reactor. Culmination would occur between Earth and Jupiter so it would be reflected against the optimum area once reaching Jupiter orbit.<br />For solar thermal propulsion it’s a much greater problem. Culmination has to occur against the point of against the boiler to create the maximum possible heat. This means that the reflector must be continually modified to create that effect. It could either be slowly moved away from the boiler to maintain columniation. Or the angle of the reflector could increase as it got further away.<br />Who would have though that my simple knowledge of amateur astronomy would ever come in play when describing interplanetary spacecraft.<br /><br /><font color="yellow">I have never heard of a solar thermal reactor as such and am of course quite well aquainted with the</font>
 
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spacechump

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<i>For solar thermal propulsion it’s a much greater problem. Culmination has to occur against the point of against the boiler to create the maximum possible heat. This means that the reflector must be continually modified to create that effect. It could either be slowly moved away from the boiler to maintain columniation. Or the angle of the reflector could increase as it got further away. </i><br /><br />Exactly. He seems to think he can get a constant amount of concentrated sunlight to a specific focus without adjustment. As you and I said, the energy flux hitting a particlular constant area changes. Concentrating just focuses the energy you <i>can</i> collect into a more efficient area. He can a) increase the size of his collector as he moves away to collect more energy or b) adjust the focus because he can't achieve a perfect focus anyhow (but that doesn't really increase the amount of collected sunlight anyhow, its just a way to keep the boiler as efficient as possible).<br /><br />But why go to all that trouble when a reactor can provide the power without the worry?
 
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SteveMick

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Ok, I'll give this one more try.<br /> Parabolic concentrators form an image at the focus. This image has a finite size. This image is larger near the Sun and smaller farther away. Therefore the intensity of sunlight at the focus remains the same as you move farther from the Sun. It is true that the total energy intercepted by the concentrator goes down, but the objection was that at Jupiter a thermal engine would have to operate at a lower temperature and therefore efficiency. The operating temperature of a solar thermal rocket engine would obviously remain constant while the mass flow rate would decrease so that thrust would be much less.<br /> My frustration has been twofold. First this is hardly a difficult concept and if the supposition is made that I just might know what I'm talking about instead of referring to legitimate and accurate arguments as "crap" etc., then perhaps the discussion would move in a more useful direction. As you must have noted, I thank people for their comments and am grateful for well thought out criticisms. Secondly Three times now I have tried to get the conversation back to the topic which is JIMO and I'm very surprised that even a great fan of nuclear wouldn't have some reservations about the current preliminary design and might want to improve it. Are there any people who have their own ideas about this out there or does everyone like the Emporer's new clothes?<br /> Mmorris again refuses to actually read what I have written and respond to that. I have at no point stated that a gravity assist at Venus would do anything other than, in this case, get the probe closer to the Sun at perihelion. At perihelion, the probe would fire up its thermal engine to provide the required thrust to change the plane of its path relative to the ecliptic. I beleive the ides that I was somehow using a gravity assist to change the plane took on a life of its own in mmorris's mind. <br /> Interestingly the concept I have laid out has apparently survived sin
 
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najab

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><i>This image has a finite size. This image is larger near the Sun and smaller farther away. Therefore the intensity of sunlight at the focus remains the same as you move farther from the Sun.</i><p>Let's take this step-by-step. A parabolic mirror (or concentrator) has the property that incoming light rays parallel to the directrix are focused to a single point. So the issue of "image size" doesn't matter - all the rays are focused to one point.<p>You acknowledge that "the total energy intercepted by the concentrator goes down", so how can the intensity of sunlight at the focus remain constant? You're focusing less energy to the same point.<p>><i> Mmorris again refuses to actually read what I have written and respond to that....I have at no point stated that a gravity assist at Venus would do anything other than, in this case, get the probe closer to the Sun at perihelion. At perihelion, the probe would fire up its thermal engine to provide the required thrust to change the plane of its path relative to the ecliptic.</i><p>I believe that you are the guilty party here, you have completely ignored the central point that mmorris was making: it doesn't matter if the plane change is achieved using a gravity assist or by engine burn alone - if you make are in a heliocentric orbit and make a plane change, <b>you will NEVER</b> be able to orbit Jupiter or it's moons.<p>Also, you have ignored the fact that plane changes are best made at apoapsis - plane changes at periapsis require <b>the most</b> delta-V. I'm not the person to make the calculations but a SWAG would say that you would need 30km/s or so of delta-v to change into a polar orbit around the Sun at perihelion and much, much less at aphelion.<p>><i>Interestingly the concept I have laid out has apparently survived since no technical objection has been made to the central design issue which is the power source.</i><p>No, that is not</p></p></p></p></p></p></p>
 
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bobvanx

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Only one more try...?<br /><br />Steve, thanks for getting clear about your presentation. You might be interested to know that I have understood your points, ideas, solutions when you present them, and so this isn't a matter of being more clear on your part for my benefit. I got it, and answered your points accurately, using known physical principles.<br /><br />Clarity, however, might help as we endeavor to teach you where your understanding of physics can be improved.<br /><br />At no time have I told you that a parabolic reflector's image at one distance or another would be less "intense." Nor has anyone else here. What we've tried to explain, and apparently failed so far, is that <i>this doesn't matter.</i><br /><br />I drew a small diagram which you'll see below to show the difference in size of the image that will be resolved at Earth and at Jupiter. Yes, the temperature at the center of each image of each image is going to be the same (or nearly so). That's different than the heat that will be generated. Thankfully! Because otherwise we'd be burning holes in our CCD's on every telescope in the world. Think about <i>that</i> for a minute!<br /><br /><font color="yellow">Interestingly the concept I have laid out has apparently survived since no technical objection has been made to the central design issue which is the power source. </font><br /><br />Excuse me!? If we were in the same room, I'd have to wonder if you were deaf. There have been numerous explanations regarding using solar at Jupiter! I'm baffled that you missed them.<br /><br />The collector is collecting far less energy. Read that again.<br /><br />The energy that is being collected <i>is</i> being directed to a smaller area, so while you might have a nice hot spot with the smaller image, it's so much smaller that your engine is operating with 25x less energy. Therefore, you have to compensate somehow. <br /><br />So go ahead and keep telling us that sunlight at the focus remains intense. We know that. Look at our
 
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bobvanx

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One thing that Steve is confused about is that a parabolic reflector for collecting energy is not going to be "tuned" to create an image. I'd guess he's got some knowledge about telescopes, and so that's his frame of reference.<br /><br />You are correct, najaB, that "image size" doesn't matter, but Steve hasn't understood that yet. we've gone around and around, showing that the energy collected is 25x less, so the pinpoint at the focus is going to have 25x less heat, but he can't move off from "image size."<br /><br />Perhaps I foolishly tried to use the frame of reference he's comfortable with to explain the physics to him, because it could be interpreted as you and I not having similar understanding of the physics involved.<br /><br />But we do, we're simply saying the same thing two ways.
 
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scottb50

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The only way to compensate for distance from the Sun is more area in photocells, or more parabolic reflectors for collecting energy, their effectiveness diminishes over distance from the Sun. Also the reflector type system requires added mass to produce electricity that photovoltic cells do not, heating a fluid and driving a generator. That is a simple design problem though, not a show stopper. There is not a shortage of solar cells and they are cheap and lightweight, the only elaborate parts are pointing and the structure to hold the cells.<br /><br /> I still think my ideas of usimg solar power to bank Hydrogen and Oxygen for use in fuel cells would provide a far safer and lighter weight alternative to nuclear reactors. Multiple fuel cells and multiple hydrolizers offer lot more options in redeundancy than nuclear.<br /><br /> <br /><br /> <div class="Discussion_UserSignature"> </div>
 
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yurkin

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Scott<br />It’s not a question of show stoppers. Nobody doubts that the system Steve is describing would work. It’s a question of working better.<br />If you look at energy/mass; energy/volume; energy/complexity; its all heavily weighted towards a nuclear option, over any possible solar energy system.<br />Plutonium can get 1 kW/kg, solar cells don’t get anywhere near that level.<br />The entire reactor can fit into a 5 gallon drum, again no need for a hundred square meters of solar cells or a collector.<br />One could argue that the photovoltaic system is intrinsically simpler then nuclear. But once you get into the problem of unfurling it, and orientation it becomes more complex.<br /><br />This is true at Jupiter’s distance the question is where exactly is that line. If we wanted to send a 200kW orbiter to Mars would it be better to have it nuclear or solar powered. Of course it’s not as simply as choosing between the two. It may even be that the best system would be a hybrid nuclear, solar thermal, reactor. <br />Just a thought.<br />
 
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yurkin

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There’s something that’s been bothering me, about the first Presidential debate. When Kerry was asked about bunker busting nuclear weapons, he said “Not this president. I'm going to shut that program down.” This made me worry if bunker busters aren’t safe maybe Prometheus isn’t either. Or maybe I’m just reading too much into it.<br /><br />I don’t mean to start a political thread in the M&L forum. I was just wondering, has Senator Kerry said anything specific about Prometheus one way or the other?<br />
 
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najab

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><i>I don’t mean to start a political thread in the M&L forum. I was just wondering, has Senator Kerry said anything specific about Prometheus one way or the other?</i><p>No.<p>And that answers yurkin's question. <b><u>NO FURTHER DEBATE/ARGUMENT IS REQUIRED.</u></b> If you feel the need to debate/argue this issue, please start a thread in Free Space.</p></p>
 
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