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Thread: Heavy-lift boosters?

  1. #31
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    The Russians are proposing launchers to lift 80 and 160 metric tons into low Earth orbit.

    http://en.ria.ru/russia/20140128/186987052.html

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    Quote Originally Posted by selvaarchi View Post
    The Russians are proposing launchers to lift 80 and 160 metric tons into low Earth orbit.

    http://en.ria.ru/russia/20140128/186987052.html
    Well even the SLS is on firmer ground than that; course they could probably have gotten to the moon for the cost of the Sochi Olympics...

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    Quote Originally Posted by lpetrich View Post
    Plasma windows? Fused quartz? Nuclear lightbulbs?

    Any good references on these?


    Nuclear thermal rocket - Wikipedia mentions that some proposed nuclear-thermal engines could get thrust-to-weight ratios up to about 7:1. But that's not nearly as good as what some chemical engines can do: 70:1. So a nuclear-thermal rocket won't make a good lower stage. In fact, I don't know of any good alternatives to chemical-reaction rocket engines for getting off the Earth's surface into outer space. The Earth's gravity requires high thrust to escape it, and the Earth's atmosphere interferes with alternatives to rockets like linear-motor guns.
    I was under the impression that some of particle bed LANTR (LOX Augmented Nuclear Thermal Rocket) engine designs could achieve theoretical T/W ratios as high as 75:1 range, even half that should be more than sufficient for primary booster duty. Say 6 such engines, total thrust in the 4.5 million lbs region with an ISP of ~600sec.
    Last edited by Trakar; 2014-Feb-08 at 04:55 PM.

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    Quote Originally Posted by Elukka View Post
    I'm not so sure. Yes, some people would make noise, but would it amount to anything? We keep launching RTGs and to my knowledge we've never refrained from using them due to people fussing about it.
    RTGs don't pass coolant through their core and eject it through a nozzle. This seems qualitatively different than an entirely contained, solid-state machine.
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    Quote Originally Posted by Garrison View Post
    Well even the SLS is on firmer ground than that; course they could probably have gotten to the moon for the cost of the Sochi Olympics...
    That's for sure. By pursing SLS, Russia and China are looking into their own HLV programs. So even if each country only launched once every year or two--if all three launch on the same day, that's 300 tons in orbit at once.

    That's how you go to space.

    Quote Originally Posted by Garrison View Post
    Well even the SLS is on firmer ground than that; course they could probably have gotten to the moon for the cost of the Sochi Olympics...
    That's for sure. By pursing SLS, Russia and China are looking into their own HLV programs. So even if each country only launched once every year or two--if all three launch on the same day, that's at least 300 tons in orbit at once.

    That's how you go to space.

    Some news on SLS

    http://www.zerognews.com/2014/01/15/...say/#more-2945
    http://newpapyrusmagazine.blogspot.c...r-highway.html
    http://www.beyondearth.com/spotlight...-launch-system
    http://whnt.com/2014/01/31/sls-progr...iggest-rocket/
    Last edited by publiusr; 2014-Feb-08 at 09:18 PM.

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    If each country mentioned had a 100 ton launcher that launched every year or two, that's ~200 tons/yr into orbit. That's hardly anything special - we already launch way more than that to orbit every single year. Heck, if SpaceX launches their entire set of planned flights next year (which is admittedly questionable), they will, by themselves, launch vehicles with a combined capacity of 224 metric tons to LEO, and that only includes a single Falcon Heavy flight. I doubt they will actually achieve this number of launches (though to make another comparison, ULA launches ~10-12 successful flights a year just fine), but still, it shows pretty clearly that a couple hundred tons a year isn't anything special.

    (Now, if you were talking about the kind of flight rates we were doing with the Saturn V in 1969, that'd be different, but nobody has seriously proposed that kind of flight rate for a new heavy lifter)

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    Quote Originally Posted by swampyankee View Post
    RTGs don't pass coolant through their core and eject it through a nozzle. This seems qualitatively different than an entirely contained, solid-state machine.
    RTGs and reactors are very different but the kind of anti-nuclear political issues we were talking about generally have little to do with actual risk analysis and the nature of the machine. I mean, opposition to Cassini was based on the wild idea of the RTG severely contaminating all of Florida in case of launch failure.

    That's not to say safety issues can be ignored. What I hope is that it's not a political non-starter before they can even be considered.

    Quote Originally Posted by publiusr View Post
    That's for sure. By pursing SLS, Russia and China are looking into their own HLV programs. So even if each country only launched once every year or two--if all three launch on the same day, that's 300 tons in orbit at once.

    That's how you go to space.
    This sounds like an extraordinarily expensive way to go to space. These sort of programs have standing costs, in NASA's case several billion a year. Those costs will be incurred regardless of how many (or if any) rockets are launched. If you launch once a year the launch will practically cost a few billion which is in no way economical. You need a relatively high launch rate. SLS is doomed to exceedingly high costs already by not having that.
    Last edited by Elukka; 2014-Feb-09 at 12:21 PM.

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    Any means of getting to space is expensive.

    The safe thing to do is to limit the handling of liquids. Now we all remember the trouble with just one helmet filling with water, right. Depots are just asking for trouble. So you launch full modules, link quickly, and keep propellant handling to a minimum. That and the boil off of hydrogen to the tune of 20 million per month, means you really aren't saving much in the way of money http://www.spacesafetymagazine.com/2...t-fuel-depots/ http://www.thespacereview.com/article/1447/1

    Besides, the standing costs are not in fact a disadvantage. Where NewSpace gasps at the "standing armies" I find them to be standing constituencies, who find political support. It would make logistic sense if everything were based in Florida only--but then you would lose political support, and a lot of funding with other states left with a bad taste in their mouths.

    There was this line from Doctor Who which states that the soufflé isn't the soufflé, the recipe is the soufflé. SLS is not the rocket, but an engaged corp of dedicated men like what we had in Apollo, who existed beyond the lifespan of any one private company--like Marquardt or--who knows, Space X.

    This in-house capability is not a liability, but an asset that acts as a force driver, a constituency. The one thing MSFC was put on this Earth to do is build big rockets. That they gave up on Venture Star--a real cost hog, and are working on something much more do-able in recovering the Saturn mojo, is to be lauded.

    Here is an interesting post that you may find persuasive http://voices.yahoo.com/who-right-sp...-12305322.html

    Nice quote from the comment section here:

    "Many of these limits and assumptions placed on progress seem to me either arbitrary or instigated by the constant howling of private space advocates that 'it’s too expensive.'”
    http://www.spudislunarresources.com/...tier-of-space/
    Last edited by publiusr; 2014-Feb-09 at 08:42 PM.

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    Quote Originally Posted by publiusr View Post

    Besides, the standing costs are not in fact a disadvantage. Where NewSpace gasps at the "standing armies" I find them to be standing constituencies, who find political support. It would make logistic sense if everything were based in Florida only--but then you would lose political support, and a lot of funding with other states left with a bad taste in their mouths.

    There was this line from Doctor Who which states that the soufflé isn't the soufflé, the recipe is the soufflé. SLS is not the rocket, but an engaged corp of dedicated men like what we had in Apollo, who existed beyond the lifespan of any one private company--like Marquardt or--who knows, Space X.
    The SLS is a job creation program sponsored by Congress; any actual space exploration would be completely coincidental.

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    Quote Originally Posted by Garrison View Post
    The SLS is a job creation program sponsored by Congress; any actual space exploration would be completely coincidental.
    I agree. But I believe that even deep down in the pockets of those who administrate this corrupt spending, there's some genuine wish to make that go to space. And if not canceled soon, SLS and Orion will likely be around for a decade and more. They might be used as pieces in the jigsaw-puzzle which could put some actual mission together. Just add a habitat module, artificial gravity, nuclear power source, some other stuff. Cooperating with foreign space agencies and private enterprises which could provide some of those compontents. Making that potential coincident happen, we could go somewhere! I'd rather see the SLS take off with Orion, than not.

    Just like Wernher von Braun took a crooked governmental way to space, but he did help alot to push us into the space age. He prefered the V2 rather than nothing.

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    Quote Originally Posted by Local Fluff View Post
    Just add a habitat module, artificial gravity, nuclear power source, some other stuff.
    I think it will be a lot more complicated, expensive, and time-consuming to do all those things than the words "just" and "some other stuff" imply.

    Simulating gravity is something we have yet to accomplish even in LEO. Nuclear power sources are highly controversial. And we have yet to come up with any life support system that can keep a habitat module habitable for long without extensive Earth-launched resupply.
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    Quote Originally Posted by Noclevername View Post
    Simulating gravity is something we have yet to accomplish even in LEO.
    Have we even made a serious effort?
    For what we have needed thus far, microgravity has been an advantage, and we have shown different ways to minimize the effect of long term microgravity.
    I'm not saying it won't be needed. Just that it hasn't been a priority, so the money isn't spent.

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    Quote Originally Posted by NEOWatcher View Post
    Have we even made a serious effort?
    For what we have needed thus far, microgravity has been an advantage, and we have shown different ways to minimize the effect of long term microgravity.
    I'm not saying it won't be needed. Just that it hasn't been a priority, so the money isn't spent.
    True. But the reasons why we haven't yet done it don't bring us any closer to accomplishing it, so I didn't include that in my answer, which was addressing Local Fluff's comments about how easy it seemed. We still need to put a non-trivial amount of research and engineering into it.
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    Quote Originally Posted by Noclevername View Post
    Simulating gravity is something we have yet to accomplish even in LEO.
    It is very well understood physics.
    Nuclear power sources are highly controversial.
    Politically in the West today, yes. But more rational organizations may not care about that irrational temporary fashion trend over here.
    And we have yet to come up with any life support system that can keep a habitat module habitable for long without extensive Earth-launched resupply.
    Eh, no! Recycling experiments have been done on Earth. Year+ stay on LEO space stations have been done.
    Setting off for Mars today is much easier than it was to go to the Moon 50 years ago. Back then they had no clue about many things, today all components are mature technology.

    The fact that the US government for unmotivated reasons refuses to leave LEO, is not an argument for why it would be difficult to do so. I'm sure that NASA wqill never ever go to Mars. But other will! NASA will soon be abolished, as it recently was during the temporary budget ceiling issue. NASA is the first part of the government which will be suddenly abolished. Next time permanently. But the competence in today's NASA will emigrate and do their thing much much better under other titles. And that will be a new dawn for humanity in space.
    Last edited by Local Fluff; 2014-Feb-11 at 06:35 PM.

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    Quote Originally Posted by Local Fluff View Post
    NASA will soon be abolished, as it recently was during the temporary budget ceiling issue.
    Really?
    Almost every sector of the government was affected, not just NASA or NASA as a first strike.
    Plus; NASA was not abolished. NASA was not even closed as a whole. There were several NASA operations that remained intact during the short period.
    There were other agencies that were affected as bad as NASA and even worse than NASA.

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    Quote Originally Posted by Local Fluff View Post
    It is very well understood physics.

    Politically in the West today, yes. But more rational organizations may not care about that irrational temporary fashion trend over here.

    Eh, no! Recycling experiments have been done on Earth. Year+ stay on LEO space stations have been done.
    Setting off for Mars today is much easier than it was to go to the Moon 50 years ago. Back then they had no clue about many things, today all components are mature technology.

    The fact that the US government for unmotivated reasons refuses to leave LEO, is not an argument for why it would be difficult to do so. I'm sure that NASA wqill never ever go to Mars. But other will! NASA will soon be abolished, as it recently was during the temporary budget ceiling issue. NASA is the first part of the government which will be suddenly abolished. Next time permanently. But the competence in today's NASA will emigrate and do their thing much much better under other titles. And that will be a new dawn for humanity in space.
    Nothing was 'abolished'. A number of Federal agencies suffered problems because of the refusal to ratify the US budget.

    As to going to Mars it requires considerably more complexity in terms of mission planning and execution than anything else so far achieved in manned spaceflight and there are still technical issues that need to be resolved before such a mission could be attempted.

  17. #47
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    This discussion seems to be drifting from the topic of heavy-lift boosters and into a general discussion of manned spaceflight. As there is currently an active thread on that topic (and new threads can always be created), please do not continue this discussion here.
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    I think it's a good idea to keep a heavy lift system around. Yes, it's expensive to maintain and it may not be in constant use, but the ability to launch heavy payloads with a single rocket is great to have. For one thing, it would make building large structures in space easier. It would also be nice to have around on the day we find out that a space rock is heading our way.

    We keep a large military around and fund it even when not in use. Why not a heavy lift capacity?
    Last edited by Trantor; 2014-Feb-12 at 12:24 AM.

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    It's all well and good to have heavy-lift capability, but what would one use it for? Why would one want to launch 100+ metric tons up into LEO? Especially when one has to spend several hundred million dollars or euros or their equivalent to do so.

    To date, heavy-lift capability has had these applications:
    1. Sending people to the Moon: Apollo, would-be Soviet efforts
    2. Sending space-station parts into orbit: Skylab
    3. Sending big spaceplanes into orbit: Shuttle, Buran
    4. Sending big military satellites into orbit: Polyus

    Of the ones I've seen proposed, a return to the Moon is #1, and sending people to Mars or some asteroid is a variant of it. The Falcon Heavy is reportedly to send up some big military satellite, which is #4. I doubt if we will see #2 or #3 anytime soon, and I think that #3 is very unlikely.

    I once saw a proposal of orbiting solar power stations, but that seems like a non-starter. It's MUCH cheaper to build them here on Earth without sending them into outer space.

    Any others?

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    Quote Originally Posted by lpetrich View Post
    ... Any others?
    The other thing I've seen proposed is launching much larger space observatories... though given their probable price, that wouldn't happen very often.
    For that one, I am torn between wanting the knowledge such things could give us as soon as possible, and knowing that waiting for space-manufacturing, better robotics, and nanotech will result in the same or better being possible for a fraction of the cost of launching... but we have to wait 30 extra years.
    Forming opinions as we speak

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    Quote Originally Posted by antoniseb View Post
    The other thing I've seen proposed is launching much larger space observatories... though given their probable price, that wouldn't happen very often.
    For that one, I am torn between wanting the knowledge such things could give us as soon as possible, and knowing that waiting for space-manufacturing, better robotics, and nanotech will result in the same or better being possible for a fraction of the cost of launching... but we have to wait 30 extra years.
    When it comes to such projections, a range of 20-50+ years is probably more accurate.

  22. 2014-Feb-13, 04:41 PM
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  23. #52
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    I listened through parts of this 2 hour interview yesterday with Mark Bray who works at the SLS project and who defends it. He also seems to have political ambitions. The "Space Show" isn't the sexiest of podcasts around, but it lets people say their piece uninterrupted. And that is quite an innovative and rare concept today!

    http://www.thespaceshow.com/detail.asp?q=2185

    My impression is that this (libertarian leaning!) independant congress candidate argues that NASA needs to finance a heavy launch system because there is no commercial feasibility for private entities to do it. It's NASA or noone.

    My thought is that even if today only about 3 launches are envisioned for the SLS, once it is available, more uses for it will turn up. I think there were plans for the Saturn V to bring larger follow ups of the Voyager probes to the outer planets. A heavy lift can do many things for science and exploration, even if it's not commercially viable. And fanatsies about how government could've done it more efficient, will remain fantasies. That government does it at all at any cost is as good as it gets.

    Quote Originally Posted by lpetrich View Post
    It's all well and good to have heavy-lift capability, but what would one use it for?
    My favourite would be:

    #5. A large radio interferometer heading for beyond the 550-700 AU or so distance from where it could use the Sun as a gravitational lens. It would be no less useful while going there, than it would orbiting Earth, but once there it'd have a great view! To get that trip done within 30 years or so, would certainly require a heavy lift or two.
    Last edited by Local Fluff; 2014-Feb-13 at 04:51 PM.

  24. #53
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    Agreed

    Quote Originally Posted by Garrison View Post
    The SLS is a job creation program sponsored by Congress; any actual space exploration would be completely coincidental.
    That is not true.
    Saturn V/Apollo was more than a "jobs program," like there is anything wrong with that. Folks were pushing for things like SLS, ALS, Magnum for many years before Congress actually listened and supported it.

    Now folks were spoiled by Dan Goldin handing out the "Faster Cheaper Good Enough" Delta II sounding rocket missions--rather like how an alcoholic father gives noisy kids in the back seat a lollypop every five minutes to keep them quiet--when its best to have one filling meal at the end of the day--and that is just what SLS will enable--Europa missions, and more:

    http://www.americaspace.com/?p=48460
    http://voices.yahoo.com/who-right-sp...-12305322.html
    http://www.wired.com/wiredscience/20...-nuclear-2001/

    Nice quote from Mr. David S. F. Portree at the comment section of his site above:

    "Myself, I think there's no substitute for heavy lift. Aren't propellant depots designed to give "private" space something to do?"
    dsfp

    But we've done this one.

    There is this certain man named Rick who likes to fill space.com with junk op-eds against SLS: http://astromaven.blogspot.com/2014/...so-called.html

    As for me, I find more credible the sober words of a wise Griffin over those of a questionable Boozer.
    Last edited by publiusr; 2014-Feb-15 at 08:58 PM.

  25. #54
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    Quote Originally Posted by publiusr View Post
    Agreed


    That is not true.
    Saturn V/Apollo was more than a "jobs program," like there is anything wrong with that. Folks were pushing for things like SLS, ALS, Magnum for many years before Congress actually listened and supported it.
    Saturn V wasn't a jobs creation program but it was purely political just like the SLS. The difference is that Apollo had an objective and a plan; the best you can offer for the SLS is soundbites and maybes. Those people pushing for it were largely those in the corporations that have gotten the SLS contracts and those at NASA who had gotten a little too comfortable with the 'old boy network'. Not one NASA launcher/vehicle project has entered service since the STS, so far I can see nothing to set the SLS apart from those abandoned projects.

    "Myself, I think there's no substitute for heavy lift. Aren't propellant depots designed to give "private" space something to do?"
    dsfp
    Which has nothing to do with the current reality; if you can't defend SLS on it's merits just say so.
    As for me, I find more credible the sober words of a wise Griffin over those of a questionable Boozer.
    Adding a smilie doesn't make that any less of an ad hom.

  26. #55
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    I've seen the SLS called the "Senate Launch System", in honor of a certain Senator who is especially fond of it.

    Titled links from publiusr's post:

    New Mission Concepts for SLS With Use of Large Upper Stage « AmericaSpace
    Who is Right About Space Exploration, Neil Degrasse Tyson or Elon Musk? - Yahoo Voices - voices.yahoo.com
    NASA's Mars Design Reference Mission Goes Nuclear (2001) - Wired Science

    The third article's proposed mission seems very ambitious and expensive, with several big launches to Mars. It would be hard to justify something that may cost what 100 automated Mars rovers would likely cost. If one sends a lot of rovers there, one would get to sample much more of Mars's surface than what that proposed mission would likely do.

    Now for the first article's missions.

    Space-station parts

    The last launch of the Saturn V carried Skylab into orbit, the world's first space station. Latter-day heavy-lift vehicles could carry similar-sized modules into orbit, like Bigelow Aerospace's proposed inflatable ones.

    Planetary missions

    ICPS (Block I, 5 m wide): Jupiter: 3 mt, Saturn: 1.8 mt, Uranus: 0.13 mt
    LUS (Block II, 8.4 m wide): Jupiter: 8.5 mt, Saturn: 6 mt, Uranus: 2 mt

    Time: Jupiter: 3 yr, Saturn: 4 yr
    Possible places for orbiters: Europa, Titan, Uranus

    Space telescopes

    Advanced Technology Large Aperture Space Telescope: ATLAST
    Either 8 m single-mirror or 16 m folded-mirror
    Will do better than the Hubble Space Telescope and the in-the-works James Webb Space Telescope

  27. #56
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    Quote Originally Posted by publiusr View Post
    Agreed


    That is not true.
    Saturn V/Apollo was more than a "jobs program," like there is anything wrong with that. Folks were pushing for things like SLS, ALS, Magnum for many years before Congress actually listened and supported it.

    Now folks were spoiled by Dan Goldin handing out the "Faster Cheaper Good Enough" Delta II sounding rocket missions--rather like how an alcoholic father gives noisy kids in the back seat a lollypop every five minutes to keep them quiet--when its best to have one filling meal at the end of the day--and that is just what SLS will enable--Europa missions, and more:

    http://www.americaspace.com/?p=48460
    http://voices.yahoo.com/who-right-sp...-12305322.html
    http://www.wired.com/wiredscience/20...-nuclear-2001/

    Nice quote from Mr. David S. F. Portree at the comment section of his site above:

    "Myself, I think there's no substitute for heavy lift. Aren't propellant depots designed to give "private" space something to do?"
    dsfp

    But we've done this one.

    There is this certain man named Rick who likes to fill space.com with junk op-eds against SLS: http://astromaven.blogspot.com/2014/...so-called.html

    As for me, I find more credible the sober words of a wise Griffin over those of a questionable Boozer.
    I'm sure there's been clamour for a heavy lift launch vehicle. But isn't the key problem that Congress has been very specific about what this particular launch system should be? Rather than just approving the budget and powers for NASA to manage a project to deliver a HLV, they have said it must use this tech to come from this space (aka jobs in the relevant districts).

    Quote Originally Posted by lpetrich View Post
    The last launch of the Saturn V carried Skylab into orbit, the world's first space station.
    The world's first space station was Salyut 1.

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    Quote Originally Posted by Glom View Post
    The world's first space station was Salyut 1.
    I guess it all depends on how you look at it.
    MOL was before Salyut, but it was a combined single mission craft and was only a boilerplate anyway.
    Salyut 1 was a true multi-mission craft and considered successful. Unfortunately the only crew operate it was killed.
    Skylab was the first space station to have a crew come back alive and have multiple crew visits.
    Salyut 3 was the first non-fatal soviet mission.
    Salyut 4 was the first to have multiple crew visits.

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    MOL never flew. It was intended to be a spy platform, but automated spy satellites made it unnecessary.

    As to the outer-Solar-System missions, I worked out some numbers. For the expected payload weights,

    Block II / Block I: for Jupiter and Saturn: 3

    Block I: Saturn/Jupiter: 0.6, Uranus/Jupiter: 0.043
    Block II: Saturn/Jupiter: 0.7, Uranus/Jupiter: 0.24

    The Saturn/Jupiter ratio suggests more delta-V needed for Saturn than for Jupiter, which may be correct for getting into orbit.

    The Uranus/Jupiter ratios have a sizable discrepancy, which suggests some difference in mission profile. Their ratios are also small, suggesting an even greater delta-V.


    One can speed up going to Saturn with a gravity assist from Jupiter. These spacecraft had successfully used such an assist:

    Pioneer 11:
    Launch: 1973 Apr 6, Jupiter: 1974 Dec 3, Saturn: 1979 Sep 1

    Voyager 1:
    Launch: 1977 Sep 5, Jupiter: 1979 Mar 5, Saturn: 1980 Nov 12

    Voyager 2:
    Launch: 1977 Aug 20, Jupiter: 1979 Jul 9, Saturn: 1981 Aug 26

    Cassini:
    Launch: 1997 Oct 15, 2 Venus flybys
    Earth flyby: 1999 Aug 18, Jupiter: 2000 Dec 30, Saturn: 2004 Jul 1

    Jupiter's and Saturn's relative positions repeat once every Jupiter-Saturn synodic period, or about 19.86 (Earth) years. So the next Jupiter-Saturn opportunity has more-or-less started, and will continue until 2020 or a few years afterward. Between then and the late 2030's, a spacecraft sent to Saturn will have to go directly from the inner Solar System.

    For Uranus, the Jupiter-Uranus synodic period is 13.81 years, and the next opportunity should be around 2020 - 2022. No Uranus missions planned for then, so they will have to be direct from the inner Solar System until 2034 or so.

    So heavy-lift boosters may be necessary to get to Saturn and Uranus in the 2020's to the mid to late 2030's.

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    Quote Originally Posted by lpetrich View Post
    MOL never flew. It was intended to be a spy platform,
    That's why I mentioned only the boilerplate flew.

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    Not as big as the other rockets under development, the Russian Angara rocket is set for it's maiden flight later this year. Max payload 24.5 metric tons.Also there are plans to have a version of the Angara that will be able to lift 40 tons.

    http://en.ria.ru/russia/20140220/187...h-by-June.html
    Last edited by selvaarchi; 2014-Feb-20 at 10:05 AM.

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