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#501 2015-05-05 16:55:09

SpaceNut
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From: New Hampshire
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Re: Yet another Mars architecture

Being able to get water easily is a must as that lessons the need on recycling and further dependancies if a system should fail in the critical path of life support.

Easy access to concentrations of minerals and such are for protection and expansion of the landed crews home as that is what will allow for food to be grown and more. With exploration and science extending beyond say a kilometers distance from the habitat site.

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#502 2015-05-05 19:02:44

RobS
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Re: Yet another Mars architecture

Water, definitely. Possibly if we have good remote sensing data, we can find a place with nickel-iron (via magnetic anomalies) and gypsum (via absorption spectra). They can detect gypsum, which is an excellent construction material (wallboard). I'm not sure what else a base would need in large quantities. Possibly phosphates, but crushed basalt should be readily available via wind and water erosion, and on Earth it is a very fertile medium for plant growth once it starts to break down chemically. Generally, Mars is richer in potassium and phosphorus than Earth, and those are often bottlenecks for plant growth. A typical fertilizer is nitrogen, potassium, and phosphorus.

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#503 2015-05-06 07:33:29

RobS
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Re: Yet another Mars architecture

The Humans to Mars Conference is being broadcast live over the internet right now at http://www.space.com/17933-nasa-televis … ce-tv.html . They just gave the new NASA plan for getting humans to Mars. They use SLS with a flight rate of 2 per year, a 100-kw xenon solar electric propulsion to preposition assets (3.5 year flight time!), a deep space habitat that provides a model for a Phobos habitat as well, a 23-tonne Mars surface lander/ascent vehicle (which can also take cargo down one way, such as a surface hab). They take humans to Phobos in 2033, to the surface for a brief visit in 2039, and a 300-day surface stay in 2046. The Mars lander is developed later because of costs, so the first flight just goes to Phobos and tests the deep space part of the mission. The Mars lander can also be used to land astronauts on the surface of the moon as a test in the early 2030s. The Mars lander can only get back to low Mars orbit, so there has to be a prepositioned stage there to get the crew back to Phobos (which will serve as the orbit base for all operations). The SLS assumes 110 metric tonnes to orbit, then 130 mt later. Launches are always in pairs; for example, a launch to get the SEP and a Phobos transfer stage (using hypergolics) into high Earth orbit, then a second SLS to get the Phobos hab and a TMI stage to the same high Earth orbit. For the crew, the first launch gets the deep space hab and TEI stage into high Earth orbit and the second launch gets the Orion capsule and TMI stage into the same high Earth orbit.

The entire idea is to keep the cost UNDER the current NASA budget, adjusted for inflation. ISS funding continues to 2028. The lunar surface program is a brief blip in the late 2020s or early 2030s.

They use supersonic retropropulsion to get the lander to the Martian surface and note that SpaceX has demonstrated this technology, but that was the only reference to SpaceX. There is no assumption of international participation, though it is assumed that will happen.

Quite a few Martian orbit rendezvous. That surprised me.

They are assuming SLS, of course, because Space X can't get 130 tonnes into LEO. If they can, the architecture can be changed.

Very interesting. Q and A is still going on.

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#504 2015-05-06 07:53:09

RobS
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Re: Yet another Mars architecture

I should add that they are SO careful to stay within the current budget and the current programs (SLS and Orion) that the first Mars lander uses Nitrogen Tetroxide and hydrazine propellants. In the Q and A it was explained that there was no room in the budget to develop ISRU. But once they are on Mars, they'd first replace the NTO with oxygen extracted from the Martian atmosphere, then replace hydrazine with hydrogen (not methane) once water is found.

The Mars missions are every 4 years, also, not every 2, because of the costs. They acknowledged that international partnerships and private enterprise could accelerate the plan, but they developed the plan to be affordable within the current budget. It is phased with a series of goals so that there are enough goals spread out over time to maintain interest, because no one will fund a program to land humans on Mars 30 years from now.

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#505 2015-05-06 18:11:31

louis
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Re: Yet another Mars architecture

There can only be one comment: pathetic.

No drive, no vision.  What are they doing all this for?   It's a whole lot of fandangling effort for very little gain.

We could have a functioning colony on Mars within 10 years if we wanted, and NASA could get funding from many other space agencies and other sources of funding if they really wanted to make it happen. They don't. At least, not in any way that suggests it is a priority.




RobS wrote:

The Humans to Mars Conference is being broadcast live over the internet right now at http://www.space.com/17933-nasa-televis … ce-tv.html . They just gave the new NASA plan for getting humans to Mars. They use SLS with a flight rate of 2 per year, a 100-kw xenon solar electric propulsion to preposition assets (3.5 year flight time!), a deep space habitat that provides a model for a Phobos habitat as well, a 23-tonne Mars surface lander/ascent vehicle (which can also take cargo down one way, such as a surface hab). They take humans to Phobos in 2033, to the surface for a brief visit in 2039, and a 300-day surface stay in 2046. The Mars lander is developed later because of costs, so the first flight just goes to Phobos and tests the deep space part of the mission. The Mars lander can also be used to land astronauts on the surface of the moon as a test in the early 2030s. The Mars lander can only get back to low Mars orbit, so there has to be a prepositioned stage there to get the crew back to Phobos (which will serve as the orbit base for all operations). The SLS assumes 110 metric tonnes to orbit, then 130 mt later. Launches are always in pairs; for example, a launch to get the SEP and a Phobos transfer stage (using hypergolics) into high Earth orbit, then a second SLS to get the Phobos hab and a TMI stage to the same high Earth orbit. For the crew, the first launch gets the deep space hab and TEI stage into high Earth orbit and the second launch gets the Orion capsule and TMI stage into the same high Earth orbit.

The entire idea is to keep the cost UNDER the current NASA budget, adjusted for inflation. ISS funding continues to 2028. The lunar surface program is a brief blip in the late 2020s or early 2030s.

They use supersonic retropropulsion to get the lander to the Martian surface and note that SpaceX has demonstrated this technology, but that was the only reference to SpaceX. There is no assumption of international participation, though it is assumed that will happen.

Quite a few Martian orbit rendezvous. That surprised me.

They are assuming SLS, of course, because Space X can't get 130 tonnes into LEO. If they can, the architecture can be changed.

Very interesting. Q and A is still going on.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#506 2015-05-06 18:17:13

louis
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Re: Yet another Mars architecture

True but they don't need everything at once.

In the initial stages, the base will be tiny - there is unlikely to be a population of more than 50 people max in the first 10 years .  There will no shortage of cabling, PV panels, plastics and the like.

CO2 from the atmosphere is there for the taking, as is the solar radiation for power.

Water - obviously...no. 1 priority.

Silica, presumably, will be in abundance.

Iron ore to make tools.

A source of calcium carbonate would be good if they are going to make steel...


RobS wrote:

And we will never find everything a base needs in one place. The main things a base needs, I think, are water, nickel-iron meteorite, and perhaps copper (which is a widespread ore associated with basalt lava flows). The nickel-iron may be widepsread at the sand size and can be separated magnetically, so water is the key ingredient. I'd look for an equatorial spot with buried ice (easier to fly to Phobos and Deimos. easier to fly to any orbital inclination) and start there. There was a recent article about buried glaciers that appear to be sublimating away in Valles Marineris, so they are at an extremely low altitude, plus are on the equator.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#507 2015-05-06 20:06:34

RobS
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Re: Yet another Mars architecture

Louis, I agree this plan will probably never happen, but it is the best NASA can do, politically. They can't say "We'll build the SLS, but since the damn thing is too expensive, we won't use it." They can't say "we need $30 billion over the next ten years to get Americans to Mars." They can't expect a bigger budget and they can't close down their dozens of research centers to save money for Mars. They have to use SLS and Orion. Solar Electric Propulsion (100 kw, xenon; a very expensive fuel) justifies the asteroid redirect mission that they are required by law to pursue. It integrates it into the Mars mission and gives the Mars plan a more immediate accomplishment that they hope will excite the public (I doubt it will). They even managed to stick a single manned lunar landing into the plan in order to test the Mars lander properly (if they perform two or three such landings, they'd be able to position a hab on the surface as well, but there's no money for that!)

But this gives a vision of what they could do with Space X. The 130-tonne SLS could be replaced by 4 reusable Falcon Heavy launches. If Musk can get reusability routine and rapid launches routine, this would be easy. I'd drop the SEP tug and replace it with yet more reusable Falcon Heavies. The SEP tug will cost some billions for NASA to develop, and xenon is as expensive as gold; 100+ tonnes of the stuff will cost hundreds of millions of bucks (though it may still be cheaper than an extra SLS launch). Once the reusable Falcon Heavy flies, a fuel depot in LEO would be easy to establish. The other pieces needed are a deep space hab, adaptable for use on Phobos, Mars, and the moon, and a Mars lander. Bigelow can make the habs and Space X can make the landers.

I am waiting to see what is said about this plan. It was announced publicly and thousands must have watched it on the web. It is supposed to be published. I suspect Zubrin will have something to say about it. Once Space X announces its Mars architecture later this year, it will provide a sharp contrast with this latest NASA plan.

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#508 2015-05-06 23:21:37

RobertDyck
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Re: Yet another Mars architecture

What exactly is the price estimate for SLS? Remember, the Ares launch vehicle from Dr. Zubrin's Mars Direct is basically the same vehicle.

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#509 2015-05-07 03:54:00

RobS
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Re: Yet another Mars architecture

Does anyone know? It seems to me I have heard numbers from $500 million to $2 billion per launch. Considering it was developed old style, I suspect it's toward the higher end of that range.

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#510 2015-05-07 04:27:46

kbd512
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Re: Yet another Mars architecture

RobS,

SLS will probably cost between $1B and $1.5B per flight.  Add in ongoing development funding, maintaining facilities, and other recurring costs and we're talking about ~$3B a year to maintain the SLS program.  NASA and Congress will resort to magical thinking to explain away what SLS will really cost to fly, but $1B to $1.5B is a sound estimate.

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#511 2015-05-07 04:29:34

RobS
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Re: Yet another Mars architecture

So sad; that's 30 Falcon Heavy flights per year, able to lift 1,500+ tonnes to LEO.

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#512 2015-05-07 09:26:50

GW Johnson
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Re: Yet another Mars architecture

I see in the news that Spacex's first test of the Dragon-2 launch abort rockets went well.  They're supposed to do a real abort test off a flying booster later this year,  or so I heard. 

Testing has been rather heavy and sometimes quite loud at the Texas test site.  I hope they really will fly Falcon-Heavy this year for the first time.  Last time I heard,  that was to be out of Vandenburg,  not Canaveral. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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#513 2015-05-07 09:31:15

RobS
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Re: Yet another Mars architecture

I think the Falcon Heavy is supposed to fly out of Canaveral, possibly in July, though probably later. Nasaspaceflight.com had a good article about it a few weeks ago. The Dragon abort test was live on Space X TV and was quite fun to watch. It was an incredible irony to be listening to the NASA presentation about their latest plan to go to Mars in the 2040s at the Humans to Mars conference (live over the web) and then cut away from their PowerPoint to watch the Dragon abort test, then switch windows on the computer and resume watching the PowerPoint.

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#514 2015-05-07 11:10:40

RobertDyck
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Re: Yet another Mars architecture

I find that frustrating. According to "The Case for Mars", the cost estimate for Mars Direct was $20 billion for research, development, construction of infrastructure, plus the first human mission to Mars. Then $2 billion for each mission thereafter. That includes 2 launches of Ares, basically SLS Block 2. Including. That means hab, ERV, mission control, and full mission cost.

Wikipedia quotes a few cost estimates. It has links to news announcements.
CBC News August 27, 2014

The decision to proceed with development of the new rocket came after a review known as Key Decision Point C, "which provides a development cost baseline for the 70-metric ton version of the SLS of $7.021 billion from February 2014 through the first launch and a launch readiness schedule based on an initial SLS flight no later than November 2018," NASA said in a statement.

NASA ESD Integration August 19, 2011
I like numbers, but these charts are hard to read. It appears the President's preliminary budget included $1.8 billion per year for SLS, plus $1.010 billion per year for MPCV, plus others for a total cost of $2.5 billion per year. But the Senate Authorization Act included $2.64 billion per year for SLS, plus $1.4 billion per year for MPCV, plus others for a total of $3.894 for 2012 to $3.644 for 2016.

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#515 2015-05-07 13:01:15

RobS
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Re: Yet another Mars architecture

NASA is still living in the era of the "pork barrel space project," I am afraid. The history of the SLS ("Senate" Launch System, because the Senate imposed it on NASA when NASA didn't want it) is a case in point. I sure hope Falcon Heavy (development cost: $300 million for the Falcon 9) and the resulting lower costs to orbit will be a wake up call. It certainly has been for United Launch Alliance, Ariane, and the Russians. Let's keep spending $18 billion per year on NASA, but wisely! The number of jobs created will be at least as much! Or failing that, Robert, let the Canadians spend CDN$2 billion per year on space wisely and lead America to the moon! I bet Space X could do it for Canada, actually, if the law allowed it!

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#516 2015-05-07 14:01:20

RobertDyck
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Re: Yet another Mars architecture

Hey! I found the quarterly financial reports for the Canadian Space Agency. The last one is 3rd quarter of fiscal year 01 April 2014 - 31 March 2015. Total budget for the year is $483,589,000 in Canadian dollars. That includes CSA administrative personnel, maintenance of CSA headquarters, Canadian astronauts, resource mapping and arctic ice monitoring satellites, everything. Well, it was $300 million in 2005, so I guess it's getting better. That's one reason I looked at Russia's Energia launch vehicle, priced at $120 million US dollars per launch in 1994. But now, with Putin invading Ukraine, that's just not going to happen.

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#517 2015-05-07 19:24:03

kbd512
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Re: Yet another Mars architecture

NASA's budget woes are a direct result of our legislators dictating procurement programs to the agency.  Neither Congress nor the Senate have any vague idea of how to execute an efficient or effective procurement program, let alone how best to design a space launch system for affordability and maintainability.  That NASA's administrators are forced to continue to cheerlead for the knuckleheads in the Congress and the Senate in order to try to reconstitute our manned space program is an absolute travesty.

Designing and building a true heavy lift launch vehicle wasn't a mistake, but the arbitrary decision forced on NASA to incorporate STS hardware into SLS was a profound design mistake.  There's no way to make STS hardware remotely affordable or simple to maintain.  F9H/FH will be the launch system of choice for the foreseeable future, if affordability is a consideration.

In any event, the money to develop payloads for SLS is most definitely gone and SLS definitely won't perform like a Saturn V.  Between the poor decision making of the Congress and Senate and the indecision on NASA's part, we're not going anywhere for a long time.  If it were put to a vote, most Americans would defund the manned space program.  It's way, way past time for NASA to deliver.

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#518 2015-05-07 22:53:38

RobertDyck
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Re: Yet another Mars architecture

I saw a documentary about early years. It said Eisenhower wanted spy satellites, but the issue was establishing a president that space did not belong to countries beneath. That he could orbit satellites freely. He wanted a civilian space agency not for any sort of exploration, but just to establish that legal president. When Russia launched Sputnik into orbit, he thought Russia did him a favour, established the president. The point is government never has cared about space exploration, it's all about other covert objectives. The documentary said the American public expected America to have dominance in space, but the government really didn't care.

Soviets didn't care either, they just wanted an ICBM. The satellite was held as a reward for German rocket scientists working for the Soviet Union, after they demonstrated a working ICBM. And from the Soviet government perspective, the satellite launched on an ICBM demonstrated they could drop a nuclear bomb anywhere in the world.

Today Congress doesn't care either. Today they want jobs in their districts so they get votes. And they want contractors to donate copious quantities of cash to their campaign. If you're concerned about how much money is spent, ask how much is kicked back into Congressional election campaigns.

Right now one Canadian senator is on trial for misappropriating government funds, funnelling them into party coffers. A lot went into his own pocket, but the focus is how much went to his party. Three more senators have been charged, and the Auditor General has completed a complete review of all senator expenses. Looks like about 10% of remaining senators are in serious trouble.

So, has Congress really cared about space at all? Is this just a cash cow for their campaigns?

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#519 2015-05-08 01:32:22

kbd512
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Re: Yet another Mars architecture

It's a little more complex than you're making it out to be, Rob.

Eisenhower was indeed concerned about the Russians launching ICBM's at the US, but he was also a forward thinking man and wanted something more for America than a giant military industrial complex that pervaded every aspect of American life.  The fear of the unknown was the foundation that the military industrial complex was built on, but the scientific achievement (whether it benefited the military or society as a whole) was what has kept the institution in place.  The good that it does for our country is inseparable from the bad.  Fear is a powerful motivator.  Problems arise when the fear controls our activities.

With respect to what lead to the Russian space program, again, fear was a powerful motivator.

There are people in Congress who genuinely care about our space program, rather than just concerning themselves with votes from their constituencies.  Irrespective of how they personally feel about our space program, most of these people who make policy decisions can't balance a checkbook, much less possess the engineering background and experience required to make effective decisions on what's worth spending money to develop.  In general terms, they just don't understand much of anything about what they're making decisions on when it comes to our space program.  Moreover, why would they?  Their job is to make legal decisions.

NASA is not blameless, either.  The administrators need to be better advocates for our space program and there needs to be truth in advertising, so to speak.  For example, NASA administrators needs to be honest with themselves and others about what America requires for space exploration.

Orion may very well be the most advanced space capsule system in the world, but if it costs too much to develop, is too heavy to launch on a reasonably priced rocket, or is too small for any real space exploration, then it has no utility for space exploration.  Any manned space program is all about the humans.  This is the one area of our manned space program that requires the most development, the one that's most lacking in terms of available technology to support stated space exploration objectives, and the one area that should receive the most funding for development.

Inexplicably, NASA and Congress have decided to create a new launch vehicle and spacecraft instead of developing the technologies that makes human space exploration possible.  On the face of the issue, having a very capable rocket and a modern spacecraft would seem like a logical place to start since you obviously need a rocket to take you into space and a spacecraft for the ride up.  However, we've had a reliable spacecraft and launch system, better known as the Space Shuttle, for humans to use to get to space for three decades.  There was never any requirement to reinvent the taxi service (SLS), let alone the taxi cab (Orion), for space exploration.  That's exactly what we've done.  The end result will be no more or less reliable or cost effective than the Space Shuttle was.  In short, there was no justification for replacement of the Space Shuttle and even less justification for continuing to use Space Shuttle hardware in an expendable vehicle.

This post isn't meant to be a NASA or Legislature bash.  If someone from NASA (unlikely) or our Legislature (highly unlikely) reads this, take the point and not the arrow.  Even to a lay person, like myself, it's blatantly obvious that Orion can't take humans anywhere into deep space, apart from the moon, and that SLS isn't required for space exploration.  SLS may simplify some aspects of space exploration by negating some exploration vehicle assembly requirements, but nearly every mission architecture document I've seen from NASA involves some in-space assembly of mission hardware components.  It really doesn't matter what SLS might do for NASA if the budget only allows for one flight per year.  If you can't fly the rocket at least twice per year, then you don't need it because you can't afford it.  If you can get funding to fly it at least twice per year, fine.  If not, F9H/FH will still get the job done, even if it wasn't invented by NASA.  You'll even have money left for development of payloads that actually require heavy lift.  Kinda nifty, if you ask me.

With the level of funding that Orion receives every year, NASA could have a real deep space exploration vehicle, near closed loop ECLSS, active radiation shielding, and solar electric propulsion.  SLS may have some future utility for space probes, telescopes, and putting a deep space exploration vehicle in LEO with one flight.  Orion never will have any future utility for space exploration.  There are far less expensive taxi cabs available.

In closing, there needs to be a reprioritization of available funding if we want to go back to the moon or to go to Mars.

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#520 2015-05-08 06:29:53

RobS
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Re: Yet another Mars architecture

I agree with a lot of what you say, kbd. My hope is that some sort of balance between pork barrel and practical effort can be reached. NASA has a lot of research centers and they do abstract long-term engineering research. They need to continue, partly because they have some use and partly because they keep Congressmen happy. I don't know enough about Orion to know whether it has advantages over Dragon. Orion is supposed to be good for several years in space, so it can be used as the "command module" of a Mars mission (coupled with a deep-space hab). It is advanced, but it also doesn't have built in retropropulsion and the current version probably doesn't have a heat shield for interplanetary return velocities. If the Dragon is used for tourist flights to a Bigelow hotel, it will quickly acquire the experience of dozens of flights, will have the cash flow for improvements, and will be mass produced and thus even cheaper. So those factors will favor Dragon, by the mid 2020s. Coupled with Space X's experience with landing stages back on the Earth and its steady development of launch and EDL technology, and now its development of methane propulsion, I don't see how Space X technology won't be used for reaching Mars. The pieces are falling into place.

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#521 2015-05-08 12:16:58

RobS
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Re: Yet another Mars architecture

Here's a rather sketchy summary of the panel: http://www.space.com/29349-manned-mars- … -moon.html

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#522 2015-05-08 19:35:33

RobS
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Re: Yet another Mars architecture

Speaking of comparisons between Falcon Heavy and SLS, the Falcon Heavy may very well evolve into a 70 mt to orbit vehicle in a few years. The Falcon 9 is about to undergo a 30% increase in payload, with more thrust from its Merlin-D engines, supercooling of the liquid oxygen to densify it, and 10% larger second stage tanks. This expanded Falcon 1.1 will be flying this summer. Two of them will be the side sticks for the Heavy, which will first fly out of Canaveral in September or October. You have to wonder whether the Heavy's cargo can't get bigger. Certainly, with three cores, you could expand the size of the second stage quite a bit. A 10% increase in payload would push the Heavy from 53 tonnes to 58.3; a 20% increase would push it to 63.6; a 30% increase would push it to 68.9 tonnes.

Here's an interview with Shotwell about some of these changes: http://spacenews.com/spacex-aims-to-deb … is-summer/ . Other information comes from Musk tweets quoted in the Falcon Heavy Wikipedia article.

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#523 2015-05-08 19:55:45

RobS
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Re: Yet another Mars architecture

Ah! Here's a summary of the Mars plan, as presented in April to a small group: http://spacenews.com/jpl-study-proposes … the-2030s/

And here's a report about the public presentation on Wednesday morning that I summarized: http://spacenews.com/a-consensus-on-goi … get-there/

People are saying we need to settle on an architecture now to get there because a consensus is emerging and the public's interest is growing. But I think we need to wait to see the enlarged Falcon 9 and the Falcon Heavy fly and see their reusability develop. Those are game changers and they'll be in place by the end of the year.

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#524 2015-05-08 20:03:37

SpaceNut
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Re: Yet another Mars architecture

We can whine about heavy lift and price per pound or kg but until we can say what the mass is that is to be payload its not even worth the effort to complain about.

RobertDyck and myself have tried to narrow down what the mass is and allow for it to be totalled for the direct means to plan and layout the design for what we need for payload masses to be launched and in what size chunks.

So one of thoses masses that effect the mission is that of the lander landing mass and what must be taken to the surface with of course there being a tremendous loss of useable mass if the chunks that can bring our payload to the surface are to small as we waste it in the duplication of Mars EDL and earth launchings just to get it there.

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#525 2015-05-09 10:30:02

GW Johnson
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From: McGregor, Texas USA
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Re: Yet another Mars architecture

Actually,  if you look at it overall,  it's the lander mass that drives everything.  That's where you start. 

How many and how heavy are the items to be landed on Mars?  This is inherently affected by the related question:  are they one-way items or two-way items?  And by the other related question:  are we going direct to the surface,  or are we staging from low Mars orbit? 

Settle these,  and you have determined the bulk of the mass you have to launch.  The remainder is the manned transport vehicle or vehicles. 

The only "kicker" is the size of the lander vehicles.  If they're big enough to do some good,  they are usually too big to launch on the rockets we have,  except piecemeal.  That usually drives you to LEO assembly,  which then becomes more-or-less independent of having a giant rocket,  as long as the ones you have can fling around 15-25+ tons to LEO.  That's where price per kg becomes much more important than max payload mass on a single rocket. 

Every time I look at this problem,  the path leads me to the same LEO assembly,  LMO staging scenario.  Which in turn frees you to use reusable landing boats,  and do much more on the mission to Mars.  If the launch price per kg is cheap enough,  you can mount a rather large expedition for a very reasonable price. 

If you hamstring yourself to only large objects that only something like an SLS or a MCT can fling,  you'll never solve this problem.  Not in our lifetimes.  SLS is going to be way over $20,000/kg,  and MCT is still years and years away. 

GW


GW Johnson
McGregor,  Texas

"There is nothing as expensive as a dead crew,  especially one dead from a bad management decision"

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