Author Topic: What should the Flexible Path include?  (Read 20743 times)

Offline Namechange User

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Re: What should the Flexible Path include?
« Reply #40 on: 01/15/2010 04:16 AM »
All of which that go nowhere except for where we've been for the last 30.  Begs the question of why replace it then......

We replace it because we have to. Shuttle is on the way to retirement.

Again, it doesn't matter if you actually get your money's worth, as long as you spin it to the public in an exciting manner ("look at our cool new rocket, BIGGEST BAAAAAADEST one ever built!!!") Unfortuantely, NASA's spin doctors are notoriously poor.

Why do we have to replace it?  Please give examples.

I for one think it is very important to get your money's worth and shame on you for not thinking that.  Your excuse for why it is not important is poor and clings to the 'internet age" notion that all people are stupid and that spin doctors and talking heads can manipulate everyone.  Dare I ask if one victim has already fallen?
Enjoying viewing the forum a little better now by filtering certain users.

Offline MP99

Re: What should the Flexible Path include?
« Reply #41 on: 01/15/2010 04:51 AM »
I have trouble with the tele-operation thing. As has been said, robotic autonomy will improve over the next couple of decades.

Is anyone proposing to teleoperate a rover on the Moon? It wouldn't be as real-time as a computer game, but a three-second lag is worlds away from the infrequent bursts of comms available to the Mars rovers.

What sort of dish would be required on Earth to give continuous rover comms (whilst the Moon is above the horizon)?

cheers, Martin

Offline gladiator1332

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Re: What should the Flexible Path include?
« Reply #42 on: 01/15/2010 04:58 AM »
I think the biggest mistake we could make right now is taking one giant leap for mankind forward again. As space enthusiasts it is our nature to want to conquer to solar system by next Tuesday, but we need to keep in mind what way forward is best for exploration with the limited resources made available.

I think we need to take baby steps forward.

I think where ever possible, we need to get the smaller companies on the cutting edge of the horizon. If we think we need a lunar lander in the next decade, get SpaceX or Orbital, or any of the other small companies, working on some ideas. That way when the time comes, we already have some useful data and some ideas on paper. Use a COTS like program to develop some of the technologies and infrastructure we will need in the future, that way when the time comes to build a lunar lander, we aren't starting from square one. The same could go for a Space Tug, fuel depots, etc.


Offline Blackout

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Re: What should the Flexible Path include?
« Reply #43 on: 01/15/2010 05:25 AM »
I think a few important things are getting lost in the details here.  The first is that as soon as you have the long term in-space hab built, you can just pick whatever targets are convenient at the time to go to.

NEO's and Planetary flyby's will require the same equipment.  No NEO's nearby for a couple years?  Not ready yet to land on Phobos?  Thats cool, fly around Venus.  No one has done it before and imagine the photo op for NASA to continue public support.  Four astronauts all pictured in front of a window with Venus lit by the sun outside.

You could also flyby Mars with essentially the same equipment.  This is why Flexible Path is comparatively cheap to expensive landing sorties.  Once you have the HLV/EDS/Orion/HAB you have many, many targets to go to without additional expensive development projects.

Also before the Hab is ready (hopefully provided by international partners, otherwise this is just an American affair) you can go to L1/L2, and assemble big telescopes that will find and even image earth-like extra solar planets.  Think MER is popular?  Wait until we find a possible second earth.  All these things will help build support to get more funding.


The second thing that seems to be forgotten is that Flexible Path is 'Flexible' because of available off ramps.  If these amazing new mile stones are successful in drumming up support and more money, then all we need to add to get humans on Mars is a lander/ascent vehicle.  Same with the Moon.  Which means the time from the decision of "land on Mars" to actually happening will be relatively short.  I mean if the Hab and HLV already exist, we just need a lander, MAV, and a second hab/propulsion module to be put in Mars orbit ala DRM 3.0. 


Offline ChrisSpaceCH

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Re: What should the Flexible Path include?
« Reply #44 on: 01/15/2010 07:28 AM »
Why do we have to replace it?  Please give examples.

We have to replace it because the descision has been taken to retire the Shuttle and that descision is irreversible. Do I think it's a good descision? No. Do I think it should not have been taken? Yes. But it's no use to cry about what has been said and done. The boss has decided. We have to accept that and work from here. The only alternative now would be not to replace it at all and end goverment-sponsored HSF. That's still a possibility, btw, although I think the political risks associated with that have greatly diminished the chance of this being chosen (and if it were, that doesn't mean that commercial HSF is going to work...)

Quote
I for one think it is very important to get your money's worth and shame on you for not thinking that.

We'll, first of all, I'm not a US taxpayer, so it's not my money... ;)

Please understand this: I am a rather sarcastic and cynical person, who works in goverment and is therefore "used" to seeing waste of money and inefficiency. Do I think this is good? No. Do I agree with it? Not really. Am I fighting to change this? No, because there's no use. I learned to live with it and make the best of it. And, with time, you learn to play the system and use it to further your own ends, always understanding that you could probably get much better in an "ideal world", but we happen to live in the real world.

Quote
Your excuse for why it is not important is poor and clings to the 'internet age" notion that all people are stupid and that spin doctors and talking heads can manipulate everyone.

Are all people stupid? No, of course not. But, unfortunately, many are misinformed and manipulated by media, and it's getting worse. Is this good? No, but it's the way it is. What to do? See above.

Have I fallen? Maybe. Does that mean I am wrong? If so, we can agree to disagree.

I just think that flexible path is the path that will end up being chosen for political reasons (not just the budget, but also because "landing on the moon" sounds too much like G. W. Bush) and that this is not such a bad thing, since, if you play your cards right, you could actually do quite a bit of "telegenic" stuff that could be sold to the public and rekindle their interest in HSF, which, I'm sorry to say, the Shuttle (and associated false promises) has essentially destroyed.
« Last Edit: 01/15/2010 07:55 AM by ChrisSpaceCH »

Offline William Barton

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Re: What should the Flexible Path include?
« Reply #45 on: 01/15/2010 08:39 AM »
Chris, we all love Venus, don't we fellas?  And gals too!  Your briefly stated rationale is flawed.  That V. is less explored than M. is not germane; what we know of V. precludes landing people already, barring unforeseen technical developments.  That the upper atmo my indeed prove viable for an eventual "Cloud City" is fine, but too far away in time, compared to the amount of study already done, and the likely feasibility of the plans for M. already conceived.      

Bernie Roehl suggests, on:

http://forum.nasaspaceflight.com/index.php?topic=19548.msg525028#msg525028

that a good definition of "sustainable" might be: "able to sustain public interest in order to ensure that the program continues".  This is in contrast to the idea of "sustainable" as  "being able to make everything you need on site", or "making enough profit on industrial operations so as to pay for everything without federal support"

William Barton sez, on:

http://forum.nasaspaceflight.com/index.php?topic=19548.msg524840#msg524840

that Flex Path is generally a good idea because it presents a series of interesting milestones to the American taxpayer, "on the way to Mars", and thus may ensure sustainability because of taxpayer visibility.  As always, YMMV, and budgetary issues will always constrict things significantly.

And yes, the fifteen wait is very troublesome.  I'm opposed to any Lagrangian visits, unless we leave something there.  A small rudimentary fuel depot, for example, meant to be used on the next Flex Path mission.  This would spur development on Robert's suggestions regarding standard docking ports, which would begin enabling resupply, both routine and emergency.  Standard docking ports need to be nearer on the critical path.  At the same time, there's an interpretation which would allow that the current efforts are indeed Flex Path.

I have to disagree with OV:  "All of which that go nowhere except for where we've been for the last 30"  That's the been there, done that argument again, and it is fallacious.  Taken to an extreme, one would conclude no more robotic cars on Mars, right?  Been there, done that.

I'm not at all convinced of any energy related goals, with an eye towards beaming the power back to Earth.  We have plenty of power right here; this would be a funding diversion.  Besides, nukes are in the early stages of making a comeback.  One of the early ISRU goals, as a part of Flex Path should be making solar cells, and cracking water to O2 and H2, I think.

There's a lot of good Flex Path stuff scattered in the most unusual places on this forum.  I'll drag some of it in as I stumble on it.

John, I usually include high-Venus orbit with teleoperated rovers on my list of "Waypoints to Mars" because it's a variant goal that fits well in the extending timeline paradigm for mission types. Venus is a laudable goal for research, both manned an unmanned, but a pretty difficult target for sample return missions of any sort. One thing I would suggest is a teleoperated+autonomous Venus Science Laboratory, which would be launched by its own HLLV. A rover would collect samples and deliver them to the science lab, which would be operated from Earth most of the time, but realtime for a period of one month by the HVO flexpath crew. Yes, it would be an "enhanced-science stunt," but when you get right down to it, *all* space exploration, including all the cute little "toy cars on Mars" rovers, are just stunts. None of it has a good economic or scientific rationale, unless we serendipitously discover a crashed alien FTL starship somewhere in the solar system. What's the taxpayer return on MER, other than a sense of "way-cool?" The answer is, unprecendentedly glorious careers for a handful of space scientists. The taxpayer gets "way-cool" and Venus is as "way-cool" as anything else. Otherwise, taxpayer gets to tell the scientists to pass the hat and get their own "toy cars on Mars" money.

Offline khallow

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Re: What should the Flexible Path include?
« Reply #46 on: 01/15/2010 10:06 AM »

None of it has a good economic or scientific rationale, unless we serendipitously discover a crashed alien FTL starship somewhere in the solar system.

What makes you think that? First, MER gave us and was expected to give us significant new knowledge about the environment of Mars. That's the scientific rationale. Whether you or this hypothetical "taxpayer" thinks that is a "good" rationale is a different story.

Second, if we're to do anything significant on Mars, say like colonize it (which is in itself could become a second Earth over a few millennia), then knowledge of the environment through missions like this is a necessary precondition. Huge potential future economic benefit enabled by a current mission. There's your economic rationale. Once again, whether that rationale is "good" is a matter of taste.

My view is that if the only real rationale for a publicly funded mission is that it is "way-cool", then don't do it. But you know what? That's my viewpoint, just as your viewpoint was yours, not some generic taxpayer's.

Finally, how do you find crashed alien FTL starships? Hope one lands in your backyard? Given that we don't have an obvious starship in a museum or government lab (to my knowledge, of course) already, it sounds to me like you'd need to look for that sort of thing in order to find it.
« Last Edit: 01/15/2010 10:07 AM by khallow »
Karl Hallowell

Offline William Barton

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Re: What should the Flexible Path include?
« Reply #47 on: 01/15/2010 11:22 AM »

None of it has a good economic or scientific rationale, unless we serendipitously discover a crashed alien FTL starship somewhere in the solar system.

What makes you think that? First, MER gave us and was expected to give us significant new knowledge about the environment of Mars. That's the scientific rationale. Whether you or this hypothetical "taxpayer" thinks that is a "good" rationale is a different story.

Second, if we're to do anything significant on Mars, say like colonize it (which is in itself could become a second Earth over a few millennia), then knowledge of the environment through missions like this is a necessary precondition. Huge potential future economic benefit enabled by a current mission. There's your economic rationale. Once again, whether that rationale is "good" is a matter of taste.

My view is that if the only real rationale for a publicly funded mission is that it is "way-cool", then don't do it. But you know what? That's my viewpoint, just as your viewpoint was yours, not some generic taxpayer's.

Finally, how do you find crashed alien FTL starships? Hope one lands in your backyard? Given that we don't have an obvious starship in a museum or government lab (to my knowledge, of course) already, it sounds to me like you'd need to look for that sort of thing in order to find it.


You're mixing up three things:

1. Please tell me how you quantify the value of the scientific return from MER.

2. Explain again how the living taxpayer will benefit by the colonization of Mars in some imaginary science fiction future.

3. "Crashed alien starships" is a form of illustration by humor. And please do look up words you may not know. "Serendipitously" refers to the making of accidental fortuitous discoveries. So obviously, we can't go looking for them. (Footnote: "The Three Princes of Serendip.")

Offline Ben the Space Brit

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Re: What should the Flexible Path include?
« Reply #48 on: 01/15/2010 11:45 AM »
IMHO, "Flexible Path" means "Let's build the HLV and transfer vehicle first and worry about the final destination once it is clearer what budget and destingations are avaialble at that time."  That is okay in theory only if you can be sure of mmaintaing political interest until you reach that point.  I, for one, am a sceptical about that.

This is why I always thing that some destination is needed with a clear objective.  We cannot go to a point, just to go (although I'm sure that milestones, so long as they have pretty pictures, will impress the more sympathetic members of the press corps).  This is what William is doing with his 'Venus HERRO' idea.  At least something is perceptable as being achieved.  I also suspect that is what is behind NASA's embryonic NEO encounter program.

FWIW, I personally advocate a EML-1 or -2 destination station in place of the lunar surface base.  You can do lots of experiments about life-support systems and radiation shielding with Earth nearby in case of problems.  An EML station with long-term occupation also gives the opportunity for headline-catching things like observing a total eclipse of the sun by the Earth.

Ultimately, however, the objective must be to land on the destination world.  As technically and scientifically inaccurate as it is, people (most importantly, politicians) will not be satisfied that a destination has been truely reached until there are human boot-prints on the surface.

FWIW, my ideas (utilising the 'classic' -130 and -24x version of the DIRECT Jupiter) are something like this.

By 2015
* J-130 operational
* Orion to LEO with SSPDM

   > ISS support
   > Possible other LEO spacecraft maintenance missions (assessed on need closer to time)

By 2020
* J-24x operational
   > First crewed lunar free-return fly-around
   > First crewed lunar orbiter ('Apollo 8 Redux')
* ATV-derived spacelab module operational
   > First LEO test flight of spacecraft

By ISS Retirement + 2.5 years
Spacelab module utilisation
   > LLO short-duration orbiter (BEO test for spacelab)
   > EML Moonlab IOC (two spacelabs docked, initially)
   > First NEO encounter (Orion + ATV-Lab + EDS)

By 2025
* LSAM operational
   > First lunar landing
   > Lunar surface endurance record using cargo lander precursor

By 2030
* MTV Operational
   > Venus orbiter to test aerocapture & Earth return system
   > Phobos orbiter
   > Advanced planning for first Mars landing

Actually, I'd like the first Mars landing to take place before the end of 2030.  However, I'm trying to keep this conservative.

The underlying philosophy of this plan is a series of near-term objectives to keep the politicians focussed.  "What are you doing?" "We are building X." "Why?" "So we can [see objective above]."  By spreading out the development, you also get better utilisation of the budget.  Similarly, farming out, say, the ATV-Lab to ESA and JAXA with the US matching the development cost dollar-for-dollar, costs for the module are reduced.
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Offline khallow

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Re: What should the Flexible Path include?
« Reply #49 on: 01/15/2010 11:47 AM »

You're mixing up three things:

1. Please tell me how you quantify the value of the scientific return from MER.

2. Explain again how the living taxpayer will benefit by the colonization of Mars in some imaginary science fiction future.

3. "Crashed alien starships" is a form of illustration by humor. And please do look up words you may not know. "Serendipitously" refers to the making of accidental fortuitous discoveries. So obviously, we can't go looking for them. (Footnote: "The Three Princes of Serendip.")

1. Irrelevant. Intangible benefits can indeed be good rationales. You  use the "way-cool" argument for a good rationale. That's even less tied to something quantifiable.

2. If the imaginary science fiction future happens in a few decades, or those tax payers live a lot longer than expected. Some taxpayers also have concern for the distant future. For example, anti-nuclear protesters often show concern for harm imposed hundreds of thousands of years from now.

3. Ok, I looked up the definition of serendipity. I was right in my use. Just because something is accidental and unexpected, doesn't mean that you can't look for it. Further, unless the thing in question is blatantly obvious, which most scientific discoveries are not, then you had to be looking for it in some way in order to discover it.
« Last Edit: 01/15/2010 11:47 AM by khallow »
Karl Hallowell

Offline infocat13

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Re: What should the Flexible Path include?
« Reply #50 on: 01/15/2010 12:41 PM »
Anyone else have a problem with it being at least 15 years before we actually go anywhere?

I like the idea of flexible path but with the understanding we go somewhere quick and often.  My fear is empty points in space and just meandering around the solar system will not sustain any real support unless it happens much quicker and with more frequency than landing someplace. 

Well, part of the problem is that we're trying to cram too many things into the budget near-term.  I liked the EELV-based flexible path option, because at least with that one, you had the option of going half-way on the HLV at first (ie just doing the ACES and/or Raptor type upper stage first, then do the bigger first stage later), which would free up more money to do exploration earlier (pre-ISS retirement), and then fund the other part of the HLV upgrade after the ISS money is freed up.  It gave you more wiggle room.

For an SDLV though, you have less flexibility:

-you can't really defer the HLV without losing the infrastructure and workforce
-if you defer commercial crew, you've now pushed it past the point where it has an initial anchor market (ISS) to get its feet under it.  Nobody here likes the idea of using commercial crew launches for exploration missions, greatly increasing the probability that 10 years from now, the US will still have only one way of putting people into orbit.
-if you defer R&D again, you won't have the technologies you need (like long-duration radiation mitigation technologies, propellant transfer, etc) to make beyond-lunar exploration actually practical

In the end of course it will be the most useful stuff (commercial crew and R&D) that will get cut to fund the politically convenient, status quo, HLV work.

~Jon

the above post rings true,How long would the gap be with a Inline HLV
perhaps what will end up coming to pass is the ESA will end up doing the fuel depot mission as it could also be used to augment commercial space by extending the life of communications satillights of their customers.
« Last Edit: 01/15/2010 12:41 PM by infocat13 »
I am a member of the side mount fanboy universe however I can get excited over the EELV exploration architecture fanboy universe.Anything else is budgetary hog wash
flexible path/HERRO

Offline Downix

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Re: What should the Flexible Path include?
« Reply #51 on: 01/15/2010 12:47 PM »
Anyone else have a problem with it being at least 15 years before we actually go anywhere?

I like the idea of flexible path but with the understanding we go somewhere quick and often.  My fear is empty points in space and just meandering around the solar system will not sustain any real support unless it happens much quicker and with more frequency than landing someplace. 

Well, part of the problem is that we're trying to cram too many things into the budget near-term.  I liked the EELV-based flexible path option, because at least with that one, you had the option of going half-way on the HLV at first (ie just doing the ACES and/or Raptor type upper stage first, then do the bigger first stage later), which would free up more money to do exploration earlier (pre-ISS retirement), and then fund the other part of the HLV upgrade after the ISS money is freed up.  It gave you more wiggle room.

For an SDLV though, you have less flexibility:

-you can't really defer the HLV without losing the infrastructure and workforce
-if you defer commercial crew, you've now pushed it past the point where it has an initial anchor market (ISS) to get its feet under it.  Nobody here likes the idea of using commercial crew launches for exploration missions, greatly increasing the probability that 10 years from now, the US will still have only one way of putting people into orbit.
-if you defer R&D again, you won't have the technologies you need (like long-duration radiation mitigation technologies, propellant transfer, etc) to make beyond-lunar exploration actually practical

In the end of course it will be the most useful stuff (commercial crew and R&D) that will get cut to fund the politically convenient, status quo, HLV work.

~Jon

the above post rings true,How long would the gap be with a Inline HLV
perhaps what will end up coming to pass is the ESA will end up doing the fuel depot mission as it could also be used to augment commercial space by extending the life of communications satillights of their customers.
From what I've heard, a Phase 0 w/o upper stage can be flying within 36 months, thanks in part due to the existing history of the design (this would be, what, the 3rd time we've explored the option?).  Phase 1 w/ an RL-10 based upper stage, approx 5 years.  Phase 2 w/ J-2X based upper stage, 2017/2018 area.

Now, the Phase 0 model in some configurations can rival the Saturn for lbs-to-orbit I may remind you.
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Offline William Barton

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Re: What should the Flexible Path include?
« Reply #52 on: 01/15/2010 12:55 PM »

You're mixing up three things:

1. Please tell me how you quantify the value of the scientific return from MER.

2. Explain again how the living taxpayer will benefit by the colonization of Mars in some imaginary science fiction future.

3. "Crashed alien starships" is a form of illustration by humor. And please do look up words you may not know. "Serendipitously" refers to the making of accidental fortuitous discoveries. So obviously, we can't go looking for them. (Footnote: "The Three Princes of Serendip.")

1. Irrelevant. Intangible benefits can indeed be good rationales. You  use the "way-cool" argument for a good rationale. That's even less tied to something quantifiable.

2. If the imaginary science fiction future happens in a few decades, or those tax payers live a lot longer than expected. Some taxpayers also have concern for the distant future. For example, anti-nuclear protesters often show concern for harm imposed hundreds of thousands of years from now.

3. Ok, I looked up the definition of serendipity. I was right in my use. Just because something is accidental and unexpected, doesn't mean that you can't look for it. Further, unless the thing in question is blatantly obvious, which most scientific discoveries are not, then you had to be looking for it in some way in order to discover it.


There's clearly no basis for discussion here. Re: #3. Read the definition again. Although you can "expect the unexpected," in the sense you can anticipate *something* you didn't think of may or may not happen, you can't expect a particular unexpected event. Therefore, if something is accidental and unexpected, you can't go looking for it. Do you get that? If not, try looking up "unexpected."

Footnote: basic science is in some sense done for purposes of serendipity. If you look under a rock to see if anything is there, and there is a bug under it, that's serendipity. If you look under a rock to see if there is a bug under it, and there is, it's not. The presense of the bug is not unexpected.

Offline JohnFornaro

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Re: What should the Flexible Path include?
« Reply #53 on: 01/15/2010 01:27 PM »
William: To clarify my thoughts for you.  Research about  Venus -- fine.  V. precludes sample returns because they require landings.  In addition, the key point of my brief rebuttal of Venusian exploration was that it be put on the path later, not sooner.  Prioritization is key.  There's billions of dollars worth of missions mentioned just in the few postings above.

Sadly, I think many "generic" "consumers" fall for the "way cool" argument.  If I can slip into my sarcastic mode for a bit; they are perfectly willing to listen to "...press five to leave a callback number; press six to send a numeric page; or simply, hang up..." over and over each day, as long as the keyboard on their phone has a "sexy" layout.  I share Karl's viewpoint on "way cool".

An aside about the alien starships.  While true that finding them is more likely if one is looking for them; it is also true that we have no methodology for looking for alien artifacts.  The problem, as I see it, can be briefly stated thus:  We don't know if there's a needle in the haystack; we don't know which haystack to look in; virtually all of the haystacks are outside of the solar system; we have no idea how old the needle might be; and we don't know if it's a needle that we're looking for.   Wait a minute... what's that silver antenna sticking up in the back yard?

Ben's list is good, although I don't agree with the details totally, but his larger point is, I think, that "sustainability", in the political sense of sustained funding, could be, or might be, maintained with a specific path to follow.  If the path is codified into the legislation, it would seem that the term "flexible" would lose its meaning somewhat.  If the process of determining flexibility could find its way into the legislation, that would be a good thing.
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Online Robotbeat

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Re: What should the Flexible Path include?
« Reply #54 on: 01/15/2010 02:37 PM »
If we're going to send a manned mission to orbit Phobos, you could land on it with the mission margin of your delta-v budget. Your standard reaction control thrusters have more than enough thrust to land your spacecraft there. You might as well plan on landing there. This could be accomplished quite easily, the only limits being whether radiation for that long is an issue and whether exercize can mitigate zero-g effects for long enough that your bones don't turn to goo. An ATV could work as a decent hab.

But as much as I like flex path missions, I think we should develop a lander (single stage, that way the same design could be used as a Mars ascent vehicle) as soon as we can. Altair with the ascent stage engine and tanks deleted (and not performing the TLI burn) is probably close to enough performance already in a single stage, and ironically, it may be cheaper than for a two-stage lander.


 An unmanned sample return mission from Venus would definitely be harder than a manned mission to the surface of Mars. You're essentially having to land a full Earth launch vehicle (along with a launch tower?!) capable of launching interplanetary payloads inside a high-pressure oven, and having it launch effectively (with no ground crew) through an atmosphere at a pressure almost a hundred times denser than ours (comparable to combustion chamber!) after being loaded by an autonomous robot somehow capable of operating for long periods of time in this environment. Oh, and you guys think salt water has a detrimental effect on rocket engines? Try sulfuric acid at 900 degrees F. This mission is virtually impossible. The only reason I say it isn't 100% impossible is that maybe it could be done if launched from a blimp the size of the Hindenberg. It'd cost at least a trillion dollars. Let's explore all the moons of Jupiter, Saturn, Uranus, Neptune, Earth, and Mars first. And land on Mars, Ceres, and Mercury.
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To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Online robertross

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Re: What should the Flexible Path include?
« Reply #55 on: 01/15/2010 04:43 PM »
I'm seeing people losing a grasp on what missions need to be accomplished to justify the money being spent. Here's a refresher:

1) It starts with getting us out of desparate economic times. People working = tax revenue = reduced deficits (hopefully).

2) Education: this bring up the standard of living of the people so that more can prosper.

3) Tied into #2: We need to inspire the children, not the parents. Parents listen (or are supposed to listen) to their children. If they are enthusiastic abotu space, their parents will push for it to continue. WIth children wanting to become involved with science, space, technology, we give them a future to be involved with, and hence we need jobs for them when they come out of school.

So, we need missions that not only inspire children, but include them as well. This goes back to something I mentioned a while back: tele-operated robots on the moon operated from schools. How cool is that?

Another point on fly-by missions: If we go to these remote destinations, we should bring about landing beacons to identify prime landing spots. Much easier to cover vast terrain from above, and send down marker beacons, for future manned & unmanned missions. Another reason to get Plutonium production going, since many locations are too isolated to rely on solar power.

We would need a rack-based deployment system, with small RTG-powered radio beacons, mounted to the outside of our spacecrafts.
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Offline hydra9

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Re: What should the Flexible Path include?
« Reply #56 on: 01/16/2010 06:45 AM »
Over on:

http://forum.nasaspaceflight.com/index.php?topic=19548.msg524842#msg524842

Bernie Roehl posted what I consider to be an excellent summary of how the Flexible path could be implemented.  I include it here:

<<
First launch of Jupiter/Ares:
  * the biggest launch vehicle in the world (by far)
  * the vehicle that will take mankind to the moon, Mars and beyond
  * the dawn of the next space age

First crewed launch of Orion:
  * the rebirth of American human spaceflight
  * the first flight of the spacecraft that will take us out into deep space
  * the beginning of a new era of exploration for all of mankind

First circumlunar flight:
  * returning to the moon for the first time in half a century
  * shake-down flight of the spacecraft that will take us into the solar system

First visit to L2:
  * the farthest out into space that any human being has ever gone
  * going beyond the moon for the first time
  * visiting the staging ground for all future deep-space missions

First L2 base:
  * building humanity's first deep-space outpost
  * the first step in man's expansion into the solar system
  * the gateway to the moon, the asteroids and the planets

First NEO mission:
   * first human visit to an asteroid
   * first trip out into the solar system
   * farthest into space that any human being has ever gone (by far)
   * longest deep-space mission ever
   * preparation for future trips to the moons of Mars
   * learning more about possible future threats to human civilization
   * developing techniques to prevent future disasters

Lunar landing mission:
   * mankind's triumphant return to the moon
   * studying how to live on the moon so we can move on to Mars
   * finding ways of using the moon's resources for future missions

Phobos visit:
   * first mission to Mars
   * first landing on the moon of another world
   * preparation for an eventual human landing on Mars
>>

Comments?

Where are you going to get the hundreds of tonnes of mass shielding for a trip to an asteroid, the moons of Mars, and a permanent Langrange point outpost?

Marcel F. Williams

Offline Lambda-4

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Re: What should the Flexible Path include?
« Reply #57 on: 01/16/2010 07:49 AM »

Where are you going to get the hundreds of tonnes of mass shielding for a trip to an asteroid, the moons of Mars, and a permanent Langrange point outpost?

GRE exposure up to 180 days mission length is unproblematic.
SPE shelter is required even for an asteroid mission and SEL-1/2 mission, however this is unproblematic (get half your spacecraft in the direction of the sun, as well as the water tank and scientific equipment and hide behind it)

For a sprint Mars flyby and Mars orbital mission (450-500 days) GRE exposure is above NASA guidelines at Solar minimum. So that would require some polyethylene/water shielding (20-25g per cm²) to get below NASA guidelines for career radiation exposure.

Conjunction class 900 days Mars orbital missions are not viable with current technology due to GRE exposure at Solar minimum - as well as are prohibitive due to long-term microgravity exposure (if not mitigated by AG).

EDIT: some errors
« Last Edit: 01/16/2010 12:26 PM by Lambda-4 »

Offline Ben the Space Brit

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Re: What should the Flexible Path include?
« Reply #58 on: 01/16/2010 10:46 AM »

Where are you going to get the hundreds of tonnes of mass shielding for a trip to an asteroid, the moons of Mars, and a permanent Langrange point outpost?

GRE exposure up to 180 days mission length are unproblematic.

Thank you, Lambda-4 for standing up and pointing out that this particular dragon is, in fact, a cardboard cut out set up by the "Can't, Won't, Mustn't" squad to try to rule out HSF exploration.
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Offline Downix

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Re: What should the Flexible Path include?
« Reply #59 on: 01/16/2010 12:20 PM »

Where are you going to get the hundreds of tonnes of mass shielding for a trip to an asteroid, the moons of Mars, and a permanent Langrange point outpost?

GRE exposure up to 180 days mission length are unproblematic.
SPE shelter is required even for an asteroid mission and SEL-1/2 mission, however this is unproblematic (get half your spacecraft in the direction of the sun, as well as the water tank and scientific equipment and hide behind it)

For a sprint Mars flyby and Mars orbital mission (450-500 days) GRE exposure is above NASA guidelines at Solar minimum. So that would require some polyethylene/water sheltering (20-25g per cm²) to get below NASA guidelines for career radiation exposure.

Opposition class 900 days Mars orbital missions are not viable with current technology due to GRE exposure at Solar minimum - as well as are prohibitive due to long-term microgravity exposure (if not mitigated by AG).
Plus where we'll get it is the same place we get shielding now, from around ourselves.  The technology to bring this into space, the focus on weight-loss, will be of incredible boon to huge sectors of industry. Imagine the possibilities of new lightweight radiation shielding technology. 

It is the gravity issue I am more concerned with, but with the 12m wide fairing for Jupiter you can easily launch an integrated AG system a la USS Discovery.
chuck - Toilet paper has no real value? Try living with 5 other adults for 6 months in a can with no toilet paper. Man oh man. Toilet paper would be worth it's weight in gold!

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