NASA's Mars Plan

[Benjamin Kerman]

You have a point, but if I am interpreting you correctly, you think that the plan itself is ok?

[Tullius]

1 hour ago, Benjamin Kerman said:

1) It would be almost impossible to bring everything we need with us to Mars. If we did try to bring everything from Earth, it would require exponentially more launches and a much higher cost.

Sure, it is ridiculously expensive, but if you bring everything to Mars with you, you know the stuff that brings you back. If you for example rely on ISRU for the fuel for the trip home, you have to be pretty damn sure that it works, while bringing the fuel involves much less risks.

1 hour ago, Benjamin Kerman said:

2) Building a lunar base is not a "simulation" for Mars, as they have almost nothing in common besides being a rocky sphere.

It is a station in lunar orbit and thereby can be used as a simulation for the transfer. We neither put humans into space outside of LEO for extended periods of time, nor have we tested any of the technology for the transfer flight. Lunar orbit allows for a return within a few days if something happens, while a problem half way to Mars can't be resolved by returning earlier.

1 hour ago, Benjamin Kerman said:

3) Traditional plans cost many billions of dollars, which leads them to becoming unfunded by the government. A self-reliant single/double launch mission would cost at a maximum 10 million US dollars, and as low as 3 million.

That is why NASA is taking this baby steps. They are slowly developing as much technology for a flight to Mars as their budget permits. But if no administration in 2030s decides to push for Mars at all costs, all would have been for nothing. But if an administration decides to do it, they already have some of the technology.

On the other hand, were do you get a launch for 10 million dollars? Even SpaceX charges 60 million dollars for Falcon 9, maybe 20-30 million dollars if they get reusability working as they like. And that is without the cost of payload, which usually costs more than the rocket itself, especially if it needs to be newly developed for Mars.

1 hour ago, Benjamin Kerman said:

4) The technology used in The Case For Mars has already been proven, and all of the reactions and everything they plan to do has been around for many years. 

As are most technologies NASA plans to use. The only problem is that they were never used for that purpose and in that configuration. So you need extensive testing of all relevant components before you send a crew to Mars with no easy abort plan.

Also Mars Direct involves a Saturn V sized rocket. And what is SLS? A Saturn V sized rocket.

[Nibb31]

2 hours ago, Benjamin Kerman said:

@Nibb31 The whole thing might not be perfect, but he has several good points. 

1) It would be almost impossible to bring everything we need with us to Mars. If we did try to bring everything from Earth, it would require exponentially more launches and a much higher cost.

ISRU has yet to be proven. If you want lives to rely on it, it's going to take several design iterations. With a synod every 2 years and no resources assigned to it at this point, there is little chance of it reaching maturity in the next decade.

2 hours ago, Benjamin Kerman said:

2) Building a lunar base is not a "simulation" for Mars, as they have almost nothing in common besides being a rocky sphere. 

Nobody suggests it should be a simulation, but it would be a proving ground. There are still many similarities: low gravity, lack of atmosphere, cosmic radiation. In some areas, the Moon is harsher than Mars, so if we can develop technologies to stay alive there, then we can live anywhere.

To prove those technologies, we can't afford to wait for every 2 year synod and a 6 month journey to get the results. Using the Moon as a proving ground accelerates the development cycle dramatically.

 Besides, the Moon is our back yard. We need to learn to survive in our back yard before we can cross the ocean.

2 hours ago, Benjamin Kerman said:

3) Traditional plans cost many billions of dollars, which leads them to becoming unfunded by the government. A self-reliant single/double launch mission would cost at a maximum 10 million US dollars, and as low as 3 million.

I really doubt those numbers when a single F9 launch costs $60 million and is the cheapest way to get a meaningful payload into LEO, let alone Mars. Most of Zubrin's budget estimates are totally unrealistic.

2 hours ago, Benjamin Kerman said:

4) The technology used in The Case For Mars has already been proven, and all of the reactions and everything they plan to do has been around for many years. 

No it hasn't. Long term life support, ISRU, shielding, propulsion, landing large payloads... None of that is "proven".  They are theorized at best, but none of the engineering has been done. There are no prototypes. None of it has been tested in the field. You need a TRL of around 8 or 9 in order to send humans. Those techs are at a TRL of 2 or 3 at best, they are far from "proven".

 

[Rune]

The thing that really bugs me is actually calling it a "Mars Plan". That has to be a joke. The only thing that remotely advances our capability to do such a thing is that fancy "Deep Space Transport" in the powerpoints.

In fact, the whole business stinks of being just an excuse to use SLS and Orion... and that is doubly insulting, because the plan actually requires neither. Let's write that again, because I think the significance is great: the current "NASA Mars Plan" does not require the Gateway Station, it does not require SLS; and it actually doesn't require Orion. Yes, I just said that. Twice.

Why? Well, the end result is getting a vehicle that can do the Earth-Mars leg of the trip, with humans on board, and that is reusable. Totally behind that. I mean, it's the wrong kind of mars transfer vehicle, but hey, it's a deep space ship, and that's another discussion (but for the record, solar electric is a pretty bad idea). Also totally behind the idea of parking it in a high orbit after missions, where it can be refurbished and restocked of consumables, both fuel and life support supplies. But if you have such a vehicle, why would you need a station in lunar orbit in the first place? The vehicle is a space station more than capable of doing everything that "Gateway" does!

And here comes the really bonkers part of the whole business: if it's a vehicle capable of going to Mars and back, and then be refueled for another trip, then why the heck would you need to launch it directly to the Moon in the first place? Anything capable of going to Mars and back can get itself to a high lunar orbit, and in fact doing such a trip would be a pretty fine test of its propulsion capabilities. Launch to LEO, stupid! Then, when it's in lunar orbit, you can use it to support lunar exploration as you restock it of fuel and consumables, just like this plan envisions after the initial shakeout period. As you can see, the Gateway station is completely redundant, and its main purpose becomes to delay building the ship it's supposed to serve. And SLS becomes redundant, too, because if the total mass of the vehicle is 41mT, then there are going to be at least two launchers in service in the near future capable of lofting it to LEO for a fraction of the price. One of them has its inaugural flight late this summer, BTW, if anybody wants to bring up the likelihood of any of the three options flying. And of course you don't need Orion to resupply it, since Orion is not the thing doing the resupply, just the crew transfer. So you can just as well build two of the reusable vehicles (I know, shocking to reuse a reusable space vehicle for more than one purpose ), use one for the transit to the Moon, and then board another, fully stocked by previous flights, for the second leg of the trip. Heck, the current plan envisions commercial resupply directly to lunar orbit, right?

And after that long engineering rant, here comes the thing that has me really, really salty. After all those completely irrelevant, money-draining detours are out of the way (at the tune of 3billion/year for the SLS/Orion combo alone), guess what part of the plan has the more nebulous funding path, with no money, or alternative source of money, identified for it, and is conveniently scheduled at least two elections form now. Yup, you guessed it, the Deep Space Transport. I mean, even the freaking modules of Gateway have the option of being financed by international partners, slim as that may be, and of course Orion and SLS are protected by congress critters, but the DST is safely left to be funded by a future administration, with a supposed budget increase that has never happened in the whole history of the agency. That's right, the only thing that gets no money is the only thing that is necessary to go to Mars.

 

Rune. This is no plan to Mars. This is a farce.

Edited March 31, 2017 by Rune

[DerekL1963]

5 minutes ago, Rune said:

In fact, the whole business stinks of being just an excuse to use SLS and Orion...

Since the use of the Senate Launch System and Orion is essentially mandatory...  I don't why anyone would expect anything else.  Seriously, people don't seem to grasp that NASA is not an independent actor - and that they have to work within the bounds of reality (while the fevered imaginations of the space fanboy are completely free of limits, let alone requiring any connection to reality).
 

9 minutes ago, Rune said:

Also totally behind the idea of parking it in a high orbit after missions, where it can be refurbished and restocked of consumables, both fuel and life support supplies. But if you have such a vehicle, why would you need a station in lunar orbit in the first place? The vehicle is a space station more than capable of doing everything that "Gateway" does!

If you don't have a station...  where are your maintenance crews going to live and how will they be supported?  Where will the required tools, parts, and supplies be stored?  What will provide support services for the vehicle while various systems are shut down and opened up for maintenance?   There's a reason why practically every vehicle of land, sea, or air (especially modern, higher tech vehicles) have developed specialized support infrastructure for major maintenance rather than relying on organic assets.

[Rune]

1 hour ago, DerekL1963 said:

Since the use of the Senate Launch System and Orion is essentially mandatory...  I don't why anyone would expect anything else.  Seriously, people don't seem to grasp that NASA is not an independent actor - and that they have to work within the bounds of reality (while the fevered imaginations of the space fanboy are completely free of limits, let alone requiring any connection to reality).

I know, I know... still, if you get idiotic directions, you can still push for the most sensible way. Like a bigger vehicle launched to LEO, if you must use SLS, and then resupply on lunar orbit. Make Orion an emergency escape vehicle on that stack so it can be easily taken out if someone manages to get that money sink cancelled. Besides, being inevitable doesn't make it right, or unworthy of criticism, IMO. If it's a moronic plan to get to Mars, I will keep on thinking (and saying) that it is a moronic plan to get to Mars. You could even say I'm calling repurposed bovine waste on the whole idea, 'cause that's exactly what I'm trying to do. This is not a Mars plan.

1 hour ago, DerekL1963 said:

If you don't have a station...  where are your maintenance crews going to live and how will they be supported?  Where will the required tools, parts, and supplies be stored?  What will provide support services for the vehicle while various systems are shut down and opened up for maintenance?   There's a reason why practically every vehicle of land, sea, or air (especially modern, higher tech vehicles) have developed specialized support infrastructure for major maintenance rather than relying on organic assets.

This will not be maintenance as it's usually understood here on Earth, that thing is not really going to be 'built' up there (given this plan, the thing won't get built, period, but let's keep talking hypotheticals). The crews that get it ready would do so from the inside, basically moving supplies around, overseeing refueling ops because they look cool doing so (it would be safer if they weren't on board for that, actually), and perhaps conducting an EVA or two to connect stuff form the airlock the deep space vehicle should have (tough they could always use their capsule as an airlock). You know, just like ISS maintenance, complicated as it is, is performed from ISS, from parts delivered to it by other vehicles. The Gateway adds nothing to that, other than a bigger budget required to get started.

 

Rune. 42 billion so far on this Constellation-derived debacle, and still some people insist on throwing more good money after bad.

[Nibb31]

The DSH *is* the Mars Transport Vehicle. It's the smallest possible habitation for 4 crew members that can sustain long duration manned flights in deep space. All it needs is the SEP tug and it becomes your ride to Mars.

So the plan is to build the DSH, send crews back and forth on Orion, and then attach a SEP tug module.

[Rune]

9 minutes ago, Nibb31 said:

The DSH *is* the Mars Transport Vehicle. It's the smallest possible habitation for 4 crew members that can sustain long duration manned flights in deep space. All it needs is the SEP tug and it becomes your ride to Mars.

So the plan is to build the DSH, send crews back and forth on Orion, and then attach a SEP tug module.

Not according to the slides I've seen. The plan is to assemble a ~40mT station out of 10mT modules co-manifested with Orion, and then launch a ~40mT separate DST with much bigger solar panels, attach a logistic module to it (also co-manifested with Orion flights, but far into the murky future, we are talking ~2027 here), and use that for anything interesting.

 

Rune. Unless you can point me to a more recent source than this?

Edited March 31, 2017 by Rune

[Nibb31]

Yeah, well, we get new Mars DRMs every couple of years, I doubt that such a plan will stick. 

That's 10 launches to construct two vehicles, plus at least half a dozen crewed launches to go with it. It's not realistic.

Edited March 31, 2017 by Nibb31

[DerekL1963]

 

1 hour ago, Rune said:

The crews that get it ready would do so from the inside, basically moving supplies around, overseeing refueling ops because they look cool doing so (it would be safer if they weren't on board for that, actually), and perhaps conducting an EVA or two to connect stuff form the airlock the deep space vehicle should have (tough they could always use their capsule as an airlock).

The first two items aren't maintenance, they're provisioning.   And last example only covers stuff on the outside to connect stuff.  None of those cover major work on the vehicle's systems, especially on the interior.
 

2 hours ago, Rune said:

You know, just like ISS maintenance, complicated as it is, is performed from ISS, from parts delivered to it by other vehicles. The Gateway adds nothing to that, other than a bigger budget required to get started.

ISS maintenance to date has been limited to routine preventative maintenance and occasional corrective maintenance (in the form of replacing LRU's).  It's never had even a minor refit let alone serious systems level work of the nature that a Mars craft (which must operate for the better part of a decade without abort or escape capability) will require.  (Especially after it's second of third trip when much of the machinery will be ageing.)   In fact, the plan is that when it requires such a level of maintenance it will simply be disposed of.  (Presuming it already hasn't been disposed of.)

And the Gateway at a minimum adds something a Mars craft will almost certainly not have - the ability to dock (or berth) the multiple spacecraft required to support all of that work.  (ISS currently has a Soyuz and two Progress docked, not too long ago it had those plus a Dragon.)

[Rune]

2 hours ago, Nibb31 said:

Yeah, well, we get new Mars DRMs every couple of years, I doubt that such a plan will stick. 

That's 10 launches to construct two vehicles, plus at least half a dozen crewed launches to go with it. It's not realistic.

So we agree. The thing Gerstenmaier presented to the advisory council is, at most, a waste of good paper.

15 minutes ago, DerekL1963 said:

ISS maintenance to date has been limited to routine preventative maintenance and occasional corrective maintenance (in the form of replacing LRU's).  It's never had even a minor refit let alone serious systems level work of the nature that a Mars craft (which must operate for the better part of a decade without abort or escape capability) will require.  (Especially after it's second of third trip when much of the machinery will be ageing.)   In fact, the plan is that when it requires such a level of maintenance it will simply be disposed of.  (Presuming it already hasn't been disposed of.)

And the Gateway at a minimum adds something a Mars craft will almost certainly not have - the ability to dock (or berth) the multiple spacecraft required to support all of that work.  (ISS currently has a Soyuz and two Progress docked, not too long ago it had those plus a Dragon.)

ISS has been operating for way more than a decade, without using its abort capability. Yes it had resupply, but so can this thing. Docking multiple ships is as simple as giving it more than one docking fixture (it should have at least two, but geometry says three probably makes the most sense). The gateway station, again, adds zero capability to this thing. Remember, we are talking a SEP tug+Habitat of around 40mT, with a ~10mT logistics module attached. More like a bigger Salyut with legs than anything else. So if it needs anything done to it that requires more than a docking, you might as well launch a new one.

That is what we are supposed to get at the end of all this, BTW. A ~50mT semi-used solar-electric Salyut, and a manned Mars flyby. Oh, and a ~40mT lunar station that mirrors its capabilities, but can't move. Now somebody get me a budget projection so I can work out how many 20~50mT dumb chemical stages we could lift for the same money.

 

Rune. And if I sound salty... well, it's not your fault, guys, so sorry.

[Nibb31]

No, you're right. I don't believe in this plan more than I believe in any of the DRMs or Zubrin-powered wet dreams. Mars has always been "20 years in the future" since the 1940s, and the trend continues. It probably just means that we are simply not ready for it yet.