"Conventional" JIMO with Ares V?

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wdobner

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I couldn't help but notice that in the Wikipedia entry for the Ares V it mentions that the Ares with an upper stage would be capable of launching something like the Cassini or Galileo probe without a gravitational slingshot. This entry is uncited and I don't know if it is accurate or not. Assuming for a minute it is then presumably if the Ares V were used in conjunction with a series of gravitational slingshots in the same manner as the Galileo or Cassini probes it'd be capable of delivering that much larger a payload to Jupiter or Saturn. I would guess that with a probe that size one could put the sensor package slated for the Jupiter Icy Moons Orbiter into a probe which carries a larger fraction of chemical fuel to maneuver around the Jovian system. Of course there'd still be the need to power the ice penetrating radar and high bandwidth communications system out around Jupiter, so the nuke would likely still have to go along for the ride. It does seem something of a waste to haul a nuclear reactor all the way out to Jupiter with conventional propellants when it could likely have supplied that energy. In any event I believe NASA scrapped the Prometheus program, so I guess for now it'd end up studded with a hundred or so RTGs to supply the radar.<br /><br />Just out of curiousity, is this a doable program? I would assume that at some point there will be an advance in space power supplies similar to that promised by Prometheus. Given that, might this idea work as a kind of Orion Applications Program for before or after the moon landing? I'm afraid the math is a bit beyond my ability and available time, but I guess my question boils down to whether the chemically powered probe would be able to perform the maneuvers NASA had planned for the ion drive powered JIMO while staying within the launch capabilities of an Ares V.
 
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jimfromnsf

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1. Orion is the crew vehicle and Ares I & V are the launch vehicles for the Constellation program. So it would be Ares or Constellation "applications program"<br /><br />2. The JIMO was going to multiple launches. Ares V would allow one launch, so the basic mission could be the same<br />3. At this point, JIMO architecture would have to be redone for both launch vehicle and power source. <br />4. If JIMO is to be revived, then maybe so would the reactor. But considering the money needed for the Constellation lunar program, don't see this happening
 
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wdobner

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<i>1. Orion is the crew vehicle and Ares I & V are the launch vehicles for the Constellation program. So it would be Ares or Constellation "applications program"</i><br /><br />That's true. I was under the impression that not quite everything in the Apollo Applications Program neccesarily included the Apollo spacecraft atop the Saturn. Thus a modern program of the same type with the Orion/Ares hardware would be the Orion Applications Program. But it doesn't really matter, I had kinda intended that as a joke since we'll see if any of that stuff makes it to the moon, let alone to something afterward.<br /><br /><i>2. The JIMO was going to multiple launches.</i><br /><br />Ah, I was not aware of that. Now that I reread the stuff on JIMO I see it. I was basing what little I knew about the project from an Orbiter model which depicted it being launched by one Delta IVH. Clearly that was a somewhat optimistic simulation.<br /><br /><i>3. At this point, JIMO architecture would have to be redone for both launch vehicle and power source.</i><br /><br />I would assume that despite Juno's use of solar panels the high power requirements for JIMO would rule that out, right? <br /><br /><i>4. If JIMO is to be revived, then maybe so would the reactor. But considering the money needed for the Constellation lunar program, don't see this happening</i><br /><br />I thought one of the problems with JIMO was that somehow there wasn't enough of the working material for the ion drive. I thought someone here said NASA would have to corner the Xenon market for several in order to fill its tanks.<br /><br />Just out of curiousity did NASA scrap the HiPEP program too? If by some miracle JIMO were to come back around along with Prometheus would they at least have an appropriate ion drive propulsion system to fit it to?
 
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vulture2

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>>I would assume that despite Juno's use of solar panels the high power requirements for JIMO would rule that out, right? <br /><br />At the orbit of Jupiter solar energy is about 4% of its intensity at Earth. Juno has ~50 square meters of solar panels for 300W power; solar is not likely to practical for most missions. Most payloads beyond Mars, and all future Mars rovers, will be nuclear powered. The only question is whether it will be RTGs or reactors. Reactors make possible much higher power and are actually safer to launch, since they are fueled with highly enriched uranium which is almost nontoxic compared to the plutonium used in RTGs.
 
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spacelifejunkie

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Isn't the real issue energy storage? What chemical rocket can store its fuel for over a year and fire reliably enough for a significant delta v? In orbit around Jupiter is one thing but a small mass like Europa is nearly impossible using a chemical system. Too bad the icy moons don't have an atmosphere for aerobraking. Nuke may be the only way to go.<br /><br /><br />SLJ<br />
 
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h2ouniverse

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Classical chemical propulsion is still considered for Jupiter-Europa mission (two big delta-vs).<br />Does not leave much allowable mass for payload, but looks marginally doable.
 
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vulture2

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Yet several reactors have been launched into space over the years. If we could get over the hump of getting a nuclear-electric propulsion system flight qualified it would make possible a wide range of outer planet missions. Maybe with sufficient thrust the need for an Earth flyby could be avoided; this would eliminate a lot of paperwork since a reactor doesn't really become dangerous until it has been operating for awhile and highly radioactive nuclides have accumulated. <br />
 
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h2ouniverse

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Ceratinly. That would pave the way for many more missions.<br />But Laplace mission may not need plasmic/ion propulsion.
 
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samo

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Years ago, I proposed a "Tow module" with a large Solar Sail doubling as a crude concentrator for Solar Cells -- Nukes interfere with some of the best Chemical Composition Analysis gizmos. The AIAA jounal refused to publish when the Nd-Yg Laser I used for communications proved "an unsupportable assertation".<br /><br />Actually I'd "outed" a Secret Program: oops!<br /><br />But 20 years later, Nd-Yg s were declassified, so: why not ?<br /><br /> We could use the same thing for many missions, maybe with Forward's "Photon thruster" design. If we have a mission needing a Radar Dish -- so much the better, use it as a backup communicator. Or Visa Versa: a Kilometer-wide Radar Dish is useful for Many things (VLBI, Jupiter surface mapping, etc.) & can double as it's own propulsion (if it reflects: it's a sail) & triple, as a concentrator (for Solar cells).
 
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publiusr

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I am very glad that people are finally opening up to the uses of HLLVs like Ares V, Direct, etc.<br /><br />Humanity will not ride Delta IIs to the stars.
 
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