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#1 2015-03-17 19:26:19

SpaceNut
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Smallest Human Ascent or Descent Lander for Mars Or Earth

What is the smallest human lander and ascent vehicle for Mars Use?

I am referencing some of the talk in another topic and wanted to see if its a viable option for once a base is on the surface. I remember a movie that had the stranded astronauts on mars using the remains of a lander that was just enough to get them back to orbit to a badly hurt ship and that is what has got me thinking about this topic from what has been put forth so far.

RobertDyck wrote:

In the early 1960s, NASA worked on a light-weight low-cost crew return system. It was called MOOSE: Man Out Of Space Easiest. A large plastic bag with 2 main compartments. An astronaut in a spacesuit would climb into the front compartment, then zip it closed. Use an aerosol can to fill the back compartment. The can would have spray foam, which would quickly harden. Doing this with the astronaut inside creates a form fit around his spacesuit. And fold-out sections of heat shield to be placed over the backside. This creates an aeroshell around the spacesuit. A parachute would strap to the spacesuit chest. A couple containers of food, water, and survival kit. All fit in pockets of the large plastic bag before filling with foam. And the foam was designed to crush on impact with ground. And a hand-held retrorocket for de-orbit. Yup, this means parachuting from orbit.
http://www.astronautix.com/graphics/m/moose.jpg http://www.astronautix.com/nails/m/moose3v.jpg

With it being for Earth it needs the heavy heatshield but for Mars it could be what we are using now PICA.

Terraformer wrote:

There was also a plan to paraglide from orbit - FIRST Re-Entry Glider..

Though MOOSE would be fun, I guess, I'd prefer to take the FIRST glider out of there.

This was indicated as a failure back then but could only be used as a descent vehicle even if it could be made to work.

SpaceNut wrote:

If this was a Mars orbital bail out we would need a fast response capability to where ever the crew would land or way more supplies, plus the heat sheild would need to be made larger as well as the parachute diameter for use. Both do look in the realm of possible. The inflatable Rogallo wings would take care of the need to make the heatshield bigger and give it a better landing location accuracy.

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#2 2015-03-17 19:34:00

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

kbd512 wrote:

5. If the capsules were reusable, then our explorers could use surface vehicles and small cranes to retrieve the capsules after landing, attach the capsules to much smaller ascent vehicles on the surface of Mars, and potentially have a second way of returning to the deep space transit vehicle after their surface stay has been completed

I just think that smaller and simpler backup ascent vehicles should also be considered.

Do we necessarily have to put all of our astronauts in one vehicle?

This is what we would call a Teohold mission or minimalist design...Where are you Loius....

Even if we do come up with a one person system to land with and return back to orbit that could be reuseable what are the limits for design?

RobertDyck wrote:

Mars is a planet, with atmosphere and 0.38G gravity.

Which means parachutes and landing edl designs for each...

kbd512 wrote:

I want a micro capsule designed to survive descent to the Martian surface and a return ride back to the MTV.  It would contain an astronaut in a pressure suit seated in a removable fabric seat affixed to the walls of the capsule with bungee cords.  The astronaut's suit will contain the avionics for descent/ascent.  He or she will "plug-in" to the capsule to control the capsule.  The capsule itself will have a battery, a miniature attitude control system with enough storable propellant to de-orbit the capsule, and a manually operated parachute.

This capsule serves only two purposes, it gets the astronaut to the surface of Mars with minimal gadgetry and returns the astronaut to the MTV.  Irrespective of wether or not we have massive ascent vehicles for multiple crew members or small single crew member ascent vehicles, the requirements don't change.  However, there's a huge cost differentially associated between designing and testing a manned bucket on a parachute and a massive multi-stage ascent vehicle.  If the massive, complicated ascent vehicle fails, it likely kills everyone and the mission is over.  If one astronaut out of four or six doesn't make it back to the MTV, the mission isn't a total failure.

Using very small and light descent/ascent capsules mean using tech we already have experience with for the manned systems as opposed to something we've no experience with whatsoever.  We already have LOX/CH4 engines with the performance required to get single astronauts off the surface of Mars.  We can easily test small capsule systems on comparatively inexpensive launch vehicles and we can actually afford to test them many times and in different ways.

The reason for starting the topic for sure and means we could design within the mission envelopes of curiosity and skycrane turning it into a lander for one or two crew men if a base is already set up with preloaded habitats and supplies.

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#3 2015-03-17 19:39:36

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

kbd512 wrote:
RobertDyck wrote:

No, not inflatable. I said several times, used ADEPT. NASA is already working on a carbon fibre heat shield that can be deployed like an umbrella. It's specifically designed for payloads larger than Curiosity.

Has this carbon fiber heat shield ever flown in space?  If so, could you post a link?

This could be a good thing if it works as it reduces the mass of a small lander even more....

kbd512 wrote:

A one person capsule capable of descending to Earth from ISS in LEO or to Mars from a MTV in LMO ....

The one person capsule has other potential uses, as previously noted, but the MAV will only be useful for landing on Mars or perhaps the moon.

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#4 2015-03-18 17:40:05

louis
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

Still here SpaceNut!

I would be sceptical of super small landers.  Seems a bit of a diversion to me.

My preference would be for an Apollo style lander.  Possibly a little bigger, as I think in terms of a 3 person lander.


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

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#5 2015-03-18 17:52:52

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

I am thinking of a temporary use to land and not really trying to live in it which would make it smaller for use and as we know the longer you try to use what you land in the more massive it gets....

The other thought was to make it such that its just a taxi back to orbit, which would happen long after landing once refueled which would mean less fuel to make.

A small unit could be launched on current rockets and await the crews arrival in Mars orbit with a less massive MTV by not making the mars landers part of the out going leg.

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#6 2015-03-18 19:40:48

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

kbd512 wrote:

A one person capsule capable of descending to Earth from ISS in LEO or to Mars from a MTV in LMO or a far larger four to six person special purpose MAV that has to be landed using technology that has never flown in space, so far as I know, powered by engines that don't exist?

I'd be absolutely shocked if this multi-person MAV costs less than five billion to develop.  Why immediately go for the most expensive and technically challenging solution?

The one person capsule has other potential uses, as previously noted, but the MAV will only be useful for landing on Mars or perhaps the moon.

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#7 2015-03-18 19:45:44

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

kbd512 wrote:

I've said it before, but I'll say it again.  Start really small.  Single person landers are about working with realistic budgets and using existing technology, not giving up on something better.

Money isn't going to fall from the sky to fund heavy lift launch systems and multi-person landers.  Absent angel investors with pockets like the Marianas Trench, the kind of money needed to do the types of things we want to do with lander tech just doesn't exist right now or the near future.  NASA and Congress squandered available funding on SLS and Orion.

If we're going to pour money into a development project, let's start with the MTV and its propulsion system.  Let's design something that F9H vs SLS can lift, even if it has to be assembled on-orbit.

If there's any money left, closed loop ECLSS and active radiation shielding are higher priorities than insanely expensive landers using experimental reentry tech.  NASA had its shot to save the lunar and Mars programs by funding a lander program instead of a redundant capsule program.

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#8 2015-03-18 19:48:41

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

I do believe that there is a good place for the use of such a lander and it could be the stunt for a suicide style one way mission if enough supplies are sent to the landing site.
That is a topic that we have talked quite abit about.... One man one way suicide mission...

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#9 2015-03-18 20:10:46

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

I was thinking about using an inflatable heat shield to assist with deceleration and an aluminum alloy or composite capsule.  Although my MTV concept is detailed in another thread, I was thinking that four of these micro capsules would be locked into spring loaded launch rings on top of the swash plate.  After the MTV spirals in to LMO, the capsules are manned by suited astronauts to land on Mars.  The capsules have a clamshell design.  To use the capsule, the astronaut unlocks the service module, moves it out of the way, enters the capsule, reattaches the service module to seal the capsule, and then straps into the fabric seat.  This should be an easy task in microgravity, even in a suit.

The capsules are exceptionally simple and have two primary components.

1. Capsule - contains the astronaut in his/her pressure suit on a fabric seat bungee corded to the walls of the capsule.  The astronaut's suit contains the avionics to process sensor input and the helmet contains a display.  There are three manual controls in the capsule, attitude control, a pull ring to activate the inflatable heat shield, and a pull ring to release the parachute.

2. Service Module - contains enough storable propellant to de-orbit the capsule and maintain attitude during the initial stage of reentry, a battery, a basic sensor suite to feed information to the avionics, the inflatable heat shield, and the parachute.  Just like HIAD, the SM will shift the weight of the astronaut to steer towards the landing beacon.

The advantages to this approach are that a failure of any one capsule does not mean an instant end to the mission, which is what would happen if a multi-person lander failed during descent, the technology to land payloads that weigh 1t exist today and have been tested on Mars, and that the development and testing program would be affordable.

Ideally, after landing on Mars the astronauts would use a light truck to carry the capsule and service module to a fueled ascent rocket, launched ahead of the astronauts and fueled on Mars using ISPP, attach the capsule to the top of the rocket, and then use the capsule to return to the MTV after the surface mission has been completed, meaning each astronaut has their own ride back to the MTV.  The capsule components are so small and light that the astronauts could assemble the capsules atop the rockets with wire ropes and pulleys.  If one capsule fails to reach orbit, the entire mission isn't an instant total failure.

The general idea is to keep every aspect of LMO/Mars/LMO human delivery as simple as we can possibly make it.  For critical functionality like descent/ascent, small and simple is better on Mars.

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#10 2015-03-18 20:28:48

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

I think you are targetting something slightly modified from this image

MSL_final_assembly_2011-7372.jpg

MSL-spacecraft-exploded-view.png

The spacecraft flight system had a mass at launch of 3,893 kg (8,583 lb), consisting of an Earth-Mars fueled cruise stage (539 kg (1,188 lb)), the entry-descent-landing (EDL) system (2,401 kg (5,293 lb) including 390 kg (860 lb) of landing propellant), and a 899 kg (1,982 lb) mobile rover with an integrated instrument package

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#11 2015-03-18 20:47:26

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

Actually, I was thinking of something much smaller and lighter.  The micro capsule and service module would weigh between .5t and .75t.  The capsules aren't loaded with crap that's not required to get astronauts to the surface of Mars.  The MTV assists by forcefully ejecting the micro capsules from the swash plate.

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#12 2015-03-19 19:11:55

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

Thats metric ton? If so the Phoenix lander would be about that...

http://www.nasa.gov/pdf/226508main_phoenix-landing1.pdf

page 6

Spacecraft

Cruise vehicle dimensions: Diameter 2.64 meters (8.66 feet), height 1.74 meters (5.71 feet);
span of cruise solar arrays 3.6 meters (11.8 feet)

Lander dimensions: Height to top of meteorology mast 2.2 meters (7.2 feet), or slightly less
depending on legs absorbing impact; span of deployed solar arrays 5.52 meters (18.1
feet); deck diameter 1.5 meters (4.9 feet); length of robotic arm 2.35 meters (7.71 feet)

Mass: 664 kilograms (1,464 pounds) total at launch, consisting of 82-kilogram (181-pound)
cruise stage, 110-kilogram (242-pound) back shell, 62-kilogram (137-pound) heat
shield, and 410-kilogram (904-pound) lander That lander mass includes 59 kilograms
(130 pounds) of science-instrument payload and 67 kilograms (148 pounds) of fuel

Power: Solar panels and lithium-ion batteries

Science payload: 59 kilograms (130 pounds) consisting of Robotic Arm; Robotic Arm Camera;
Surface Stereo Imager; Thermal and Evolved-Gas Analyzer; Microscopy, Electro-
chemistry and Conductivity Analyzer; Mars Descent Imager; Meteorological Station

So using the parameters from the lander mass we would lose the mass from science payload 59 kilograms
(130 pounds), solar panels if we do not plan to use them and can survive off from the batteries mass unknown at this time, and we would lose the cruise stage 82-kilogram (181-pound).

That said the design jetisoned the backshell of which we would keep and we would need to add the door to enter and exit with which means we would need a bit more fuel to compensate for a one man landing craft.

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#13 2015-03-20 03:31:39

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

SpaceNut,

The Phoenix lander is a good analogy for weight.  I would use a HIAD and parachute combination for EDL.  These are technologies that can be tested here on Earth and later on Mars, when the tech is ready and funding is available.  We could reasonably afford to send a half dozen instrumented micro capsules to Mars using a single F9H and land them at different locations to determine what our limitations are.  More importantly, we could test our ability to precision land micro capsules near a beacon so we can avoid development of expensive multi-person landers with weeks of supplies aboard.  The money saved by not developing multi-person Apollo style landers would be better spent on the MTV and Mars surface habitat modules landed using a larger HIAD or ADEPT.

If we want to do this at all, we're going to have to focus funding on technologies that are absolutely required to land humans on Mars.  Small capsules and return rockets will work just as well as larger landers for the task of Mars descent/ascent for humans.  I would love for NASA to have funding to build and launch multiple large, multi-person landers.  The funding is simply not available and won't be in the near to mid term because of Orion and SLS.  There won't even be money to use SLS on a regular basis, which is why everything I propose uses F9H.

Everybody keeps talking about sustainable space exploration using affordable solutions, but nobody seems to actually want to do that.  Affordable looks markedly different from what we're doing now.  NASA is busily trying to re-create the Apollo program because that's the only program anyone remembers that seemed like a success.  From a goal achievement standpoint, it was successful.  From an affordability standpoint, it was a total disaster.

We now have a capsule that's heavier than Apollo that uses a rocket that's somehow less affordable than Saturn V was and doesn't have Saturn V's capability.  If humans ever fly on Ares V Lite / SLS, the development program for the damn rocket will have run for longer than the Saturn V program.  Do we really need an equally unaffordable multi-person lander to go along with that?

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#14 2015-03-20 12:48:46

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

One of the biggest reasons we can't afford to explore is the staggering cost of launch services.  To this day, with all the billions spent on affordable launch vehicles that never came to fruition, NASA is no further along than when it started.  SpaceX is the only launch services provider to date that has devised a method to return launch hardware in working order.

With SLS, even if the wildly optimistic launch cost of $500M was achievable (the contractors will ensure it never will be), for the same money we could have launched F9H five times and lifted 265t to LEO instead of 70t (90t-95t if we had an upper stage that there's no development funding for).  If launch costs for SLS are nearer to a more realistic $1B, then the mass differential is even more lopsided in F9H's favor.

Any transfer vehicle or lander vehicle solution devised should be required to meet weight restrictions of reusable launch vehicles such as the SpaceX F9 and F9H.  This necessarily means orbital assembly and multiple launches, but the solution meets criteria #1 for space exploration, which would be feasibility within NASA's existing budget while simultaneously freeing up money to fund development of all the other technologies required for space exploration.  Would it be cheaper to develop a wider payload fairing for F9H or continue with this SLS nonsense that's sucking the life out of NASA's manned space flight program?

The point to all this is that any transfer vehicle or lander solution that involves a vehicle so heavy that it requires SLS for a ride to LEO should simply be written off as impossibly expensive and therefore not feasible.  Although I've been accused of working for Boeing or Lockheed-Martin over this point of using smaller descent/ascent vehicles on Mars, that is precisely why I want smaller capsules.  I want something that is feasible with reality based budgets instead of money from heaven or a development program that is delayed for a decade or more that will, in all probability, never occur because this or that political group will remove or squander funding for it.

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#15 2015-03-20 14:45:18

GW Johnson
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

For nothing but a bailout/abort capsule,  one man only,  I would think something between MOOSE and Mercury (4000 lb) would be possible.  That's pretty close to 1 ton for descent from LEO.  Intuition only,  no hard numbers.  On Mars,  you'll likely need a somewhat different trade-off between propellants and chutes.  But about a ton ought to be in the ballpark,  and on the high side. 

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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#16 2015-03-20 21:31:16

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

The problem with launch vehicle costs is not the only point to be made as the stuff we want to place into orbit when broken down into smaller piece cause the price of what we wanted in the first place to rise rapidly as we have to dock multiple sections together that are all different to make the complete item design. So there are trade offs for getting the launcher and the payload to match more closely to what we need.

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#17 2015-03-21 08:49:28

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

SpaceNut wrote:

The problem with launch vehicle costs is not the only point to be made as the stuff we want to place into orbit when broken down into smaller piece cause the price of what we wanted in the first place to rise rapidly as we have to dock multiple sections together that are all different to make the complete item design. So there are trade offs for getting the launcher and the payload to match more closely to what we need.

SpaceNut,

That would be true if the orbital assembly operations were significantly more involved than docking a few modules, the cost differential between F9H and SLS was less significant, or there were significant issues with a module remaining in LEO for a few weeks, but none of that is applicable to the comparison between F9H and SLS.  A launch vehicle that delivers less than 50% more payload for 10 times the cost of the competing, albeit less capable, launch vehicle is not a good trade in most cases.

If we're ever to have reusable transfer vehicles, then on-orbit assembly/dis-assembly/servicing is a requirement.  Using launch vehicles of more modest lift capability is not detrimental to this goal and will force the engineers designing the transfer vehicles components to create plug-and-play solutions.

Last edited by kbd512 (2015-03-21 08:49:44)

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#18 2015-03-21 13:05:57

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

I am also wondering how large we could make a module that sets on such a landing platform using the baseline of the Pheonix lander as we could send one down to the surface empty to serve as a building block for the habitat space. Then send down cargo containers to land nearby with tanks filled with water, a seperate lander for Oxygen or more water with the electrolysis system to make it as a stage for a future started sabitier reactor for life support.

I see this as a first toehold mission with a minimal crew going to mars using what we can do today as the building block for design of a mission.

That said a 2 person MTV/ERV is much smaller to launch as the large amount of water and consumables are by far less.

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#19 2015-03-21 14:24:44

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

SpaceNut wrote:

I am also wondering how large we could make a module that sets on such a landing platform using the baseline of the Pheonix lander as we could send one down to the surface empty to serve as a building block for the habitat space. Then send down cargo containers to land nearby with tanks filled with water, a seperate lander for Oxygen or more water with the electrolysis system to make it as a stage for a future started sabitier reactor for life support.

I think JPL has the right approach for landing more massive cargo containers on Mars using HIAD / ADEPT, but if separating the cargo from the crew is a good idea for operations in LEO, then it's also a good idea for interplanetary missions.  The crewed landers need to be so small and light that we can afford to test them many times and have astronauts land them on Earth from LEO.

SpaceNut wrote:

I see this as a first toehold mission with a minimal crew going to mars using what we can do today as the building block for design of a mission.

That said a 2 person MTV/ERV is much smaller to launch as the large amount of water and consumables are by far less.

You're still talking about sending cargo with the crew.  We need to divorce ourselves from that idea for exploration purposes.  You either land precisely where you're supposed to and walk to your habitat module or you become a permanent resident.  It's not as if thorough training and testing won't be conducted ahead of time.  It's not economically feasible to have a solution for all possible contingency scenarios that far from Earth, so let's not waste time and money on it.

At this juncture, we still don't have deep space habitation module or propulsion module or closed loop life support, so multi-person landers are simply out of the running for economically feasible ways to get humans to the surface of Mars.

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#20 2015-03-21 16:04:16

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

The outbound and return Cargo is only what you eat on the way out to mars orbit from earth in the MTV/ERV and not what we need on the surface as that would already be there waiting next to the habitat or in it if we can land the massive amount using HIAD / ADEPT, which are still in the works for real heavy loads. We are talking small here within the Pheonix profile here and now ... not massive unobtainium until we have the technology well tested multiple decades down the road.

We do not explore anything until we land and set up shop even if we miss the mark we do not as we are in survival mode if we miss.

You are right we can not know all the what if senerios but we can try to prepare for some that directly effect survival.

The single or multi person lander needs none of the stuff to keep us alive as we get out and go to the habitat to live, it is an orbit to surface taxi and back once refueled.

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#21 2015-03-21 16:05:00

Terraformer
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

Re. launch vehicles, do bear in mind that even if you launch the ship as one piece (which is unlikely), you can still launch it dry and send the propellent up separately, and you can also launch it empty and outfit the habitat later. That means, even if you don't dock your fuel tanks and rocket module later (but why wouldn't you...) you still have over 50 tonnes to fit the empty habitat shell, fuel tanks, and rocket engines into. When you add in all the supplies, life support, furnishing etc, you could have something that's closer to 100 tonnes dry, using only F9H. If you *do* mount the engine stack on-orbit, and maybe another habitat module, then the entire ship can be much larger...


"I guarantee you that at some point, everything's going to go south on you, and you're going to say, 'This is it, this is how I end.' Now you can either accept that, or you can get to work." - Mark Watney

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#22 2015-03-21 19:48:24

SpaceNut
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

The design that would be able to make use of these small elements could be launched by a F9H for the Earth Departure Stage (EDS), a F9H for the Mars Transit Vehicle (MTV)/Earth Return Vehicle (ERV) which contains enough habitat space for the crew going to mars with consumables for both direction, the next F9H would contain the 2 micro mars capsules and a docking node the size of Unity filled with the supplies for the journey and finally the crew is launched in the Dragon on the last F9H which has the Mars Departure Stage (MDS) that once the other pieces are assembled is the earth descent vehicle and used to get to orbit.

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#23 2015-03-21 20:39:53

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

Terraformer wrote:

Re. launch vehicles, do bear in mind that even if you launch the ship as one piece (which is unlikely), you can still launch it dry and send the propellent up separately, and you can also launch it empty and outfit the habitat later. That means, even if you don't dock your fuel tanks and rocket module later (but why wouldn't you...) you still have over 50 tonnes to fit the empty habitat shell, fuel tanks, and rocket engines into. When you add in all the supplies, life support, furnishing etc, you could have something that's closer to 100 tonnes dry, using only F9H. If you *do* mount the engine stack on-orbit, and maybe another habitat module, then the entire ship can be much larger...

That's exactly what I was thinking.  There's no requirement to have every component of a MTV in the precise configuration required to start a Mars mission as soon as you're in LEO.  All of NASA's Mars missions require orbital assembly.  This requires loading supplies in addition to docking some modules.  What I've proposed, with respect to MTV assembly for an affordable Mars mission, has already been done numerous times to support ISS operations.

MTV assembly at ISS

F9H 1: primary module (docked to ISS until the propulsion module is mated to the MTV)

F9H 2: artificial gravity module and micro capsules (some assembly and docking to primary module required)

F9H 3: secondary module (docking to artificial gravity module required)

F9H 4: crew consumables (transfer to MTV required)

F9H 5: solar electric propulsion module (partially fueled, some assembly and docking to primary module required)

F9H 6: fuel for propulsion module (on-orbit transfer of propellant required)

ISS 1: ISS crew mates the MTV to the propulsion module for transfer to L1

MTV Orbital Transfer to L1

MTV 1: ISS crew initiates an automated transfer of the MTV to L1

MTV Exploration Crew Embark at L1

F9H 7: exploration crew use Dragon Rider to rendezvous with the MTV and then depart L1 for Mars; Dragon Rider returns to ISS for ISS crew return

In the same way that we orbited the moon before we landed on it, the first mission to Mars should be orbital only, no surface stay, so that's all that's required.  That's affordable in the near term and therefore doable.  To afford this, NASA has to end the Orion and SLS boondoggles first.  There's a difference between toys and tools.  Orion and SLS are toys.  Interplanetary transfer vehicles, closed loop ECLSS, active radiation shielding, electric propulsion, and landers are tools.

Last edited by kbd512 (2015-03-21 20:53:34)

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#24 2015-03-21 21:24:24

kbd512
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Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

Presuming no F9H is reused, that's $700M in launch costs alone, which is still less than the price of a single SLS launch.  The MTV hardware will run between $1B and $1.5B (note: this is not development costs, just what production of the hardware alone will likely cost).

Launch costs for a mission that includes a surface stay will be in the $1.5B range.  A surface mission would involve the same assembly procedure for the MTV and eight mission precursor launches to push two habitat modules and consumables to the surface of Mars ahead of the MTV.

All assembly operations will take place at ISS.  Since we insist on maintaining ISS, we should have the crew do something useful.

Last edited by kbd512 (2015-03-21 21:35:32)

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#25 2015-03-22 08:39:32

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 15,806

Re: Smallest Human Ascent or Descent Lander for Mars Or Earth

GW Johnson wrote:

For nothing but a bailout/abort capsule,  one man only,  I would think something between MOOSE and Mercury (4000 lb) would be possible.  That's pretty close to 1 ton for descent from LEO.  Intuition only,  no hard numbers.  On Mars,  you'll likely need a somewhat different trade-off between propellants and chutes.  But about a ton ought to be in the ballpark,  and on the high side. 

GW

The mercury capsule details:

The Mercury spacecraft's principal designer was Maxime Faget, who started research for manned spaceflight during the time of the NACA. It was 10.8 feet (3.3 m) long and 6.0 feet (1.8 m) wide; with the launch escape system added overall length was 25.9 feet (7.9 m). With 100 cubic feet (2.8 m3) of habitable volume, the capsule was just large enough for the single crew member. Inside were 120 controls: 55 electrical switches, 30 fuses and 35 mechanical levers. The heaviest spacecraft, Mercury-Atlas 9, weighed fully loaded 3,000 pounds (1,400 kg). Its outer skin was made of René 41, a nickel alloy able to withstand high temperatures.

Mercury_Spacecraft.png

It is sort of like what we are thinking but there would be changes to the shape, heatshield and entry for the crew to enter from the MTV as we would need to do it from inside the docking port node that it is connected to.

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