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Minimal Manned Mars Mission - 2*Briz = doable! + a NEA


DBowman

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A fly-by photo of the coal-black midnight Mars on a black sky backround.
(Because a fly-by ship will turn around the Mars above its night side).

A fly-by photo of the milky-white noon Venus clouds on a black sky backround.
(Because a fly-by ship will turn around the Venus above its subsolar side).

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17 hours ago, AngelLestat said:

Calling spacex: "a no innovative company.." is like calling Tesla: "a no innovative inventor".

Number of patents filed in 2014:

  • Boeing: 911
  • Lockheed Martin: 263
  • ULA: 2
  • SpaceX: 0
  • General Motors: 1470
  • Honda: 1099
  • Ford: 804
  • Tesla: 61
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why spacex is in the top of the space industry then?   

Who says they are? Again, Musk doesn't publish any financial records because he doesn't have to, so it's hard to say how well they are actually performing compared to the rest of the industry.

On the other hand, SpaceX's workforce is underpaid and overworked, many of them only work there 50 to 60 hours per week out of a cultish devotion to Elon Musk. It's easy to make money when you're not paying your engineers the salary that they deserve.

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Sorry, but I never said that you should no test your things...  I just said that you should use the top of the technology every time you can. Because when you not do that, all cost skyrockets.

No. You should use what's available now. Technology changes fast. Adapting and certifying the top technology every year makes the cost skyrocket.

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Those test cost nothing, the test that cost money is things you test in space, crash test, or anything that requires launch things to high altitude.

You really have no idea what you're talking about. Test campaigns costs a lot of money. In fact, if you have ever worked in any kind of industry, you'd know that it typically costs more that 50% of the actual production work. I work in software, and we actually have as many quality engineers as we have developers. The same is true for most advanced manufacturing facility. Environmental testing costs even more, because it requires specialized facilities.

Quality is expensive. Aerospace quality is even more expensive.

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The software development is the most expensive in everything related to electronics.

That's why they save money by using certified hardware with certified software.

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They are just normal laptops with normal components..  the only important there was the vibration test that depends on the quality of the manufacture company. They use win7, so they are new compared to all the things that NASA use.

They still needed to be certified through vibration testing, RF testing, electrical testing, thermal testing. You don't want the batteries to explode. You don't want RF interference with equipment on the ISS. You don't want the cooling to rely on convection. You don't want toxic or out-gassing materials. You don't want the item to become a fire hazard... 

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One of those problems is because when they start a project, they already start using old tech, then after 10 or 15 years of delay in turtle development speed, their tech has 15 or 20 years old, which increase a lot the cost because nobody remember how that thing work and you dont have support because that thing is no in the market anymore.

Also.. many other techs appear in that time which make your whole design totally outdated and pointless vs new approaches.  

No. Certified aerospace hardware has a longer support lifetime because the projects they are used in have a longer lifetime. The computers on a 25 year-old A320 or F-15 are still supported by their manufacturer.

When you're in a 15 year project, you can't afford to switch technology every 3 years and start over again. If you do that, you're never going to launch, because there is always better stuff coming out, and you will spend your time integrating new systems and writing and certifying new software over and over again. Introducing new technology in the middle of a project only introduces more delays and wastes the money you spent on the original system.

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Why orion does then?

I explained why: it uses general purpose flight computers that each run a specialized task, but are capable of running the task of another computer. You don't just carry along spare computers as dead weight for redundancy. They are interchangeable. And because they each only do limited tasks, they can be smaller and use less power than your average PC. And the software is simpler too, which means that it doesn't need to be rewritten and recertified.

It's more like RAID5 than RAID1 (look it up please). You are suggesting RAID1 (duplicate everything), the industry uses RAID5 or 6 (spread the load over multiple assets with built-in redundancy).

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This topic is being derail, and for one weird reason according to one moderator.. is always my fault..
I explain this already.. the only thing that matters is deterioration (that can be tested and even find some shielding chosen its location), and Single event upsets that are solved with software or connecting devices in parallel. 

No, there are many other requirements than "deterioration" that are necessary to certify a component for spaceflight.

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You can not run any modern app in case you found that some may be usefull.  

Flight computers don't need to run Flash or Candy Crush.

 

Edited by Nibb31
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3 hours ago, Bill Phil said:

I was referring to the ultimate return on investment. Not the redundancy. Most of the money for an all out expedition is overhead and launch costs. But once it's in orbit, it's an asset. And if it's capable of going to Mars and back four or five times, along with the rest of the fleet, then it's a better investment than the minimal mission would be.

Heck, if you're real smart about your design you could get the cost down by quite a large margin, with the same returns.

The Curiosity Rover program was 1.6 B 2009 USD, the space craft (rover and EDL I guess) was 0.94 B of that (plus maybe some of the 'other costs' were s/w etc for that), launch costs are on the way down - but mission design can blow the lauch mass requirements way up again. If you are building 'many' identical / related craft you could amortize the 'space craft develop' subset of the 0.94 B - as long as you have a lot more total money to spend. I'm all up for reusable craft to amortize construction over multiple trips; but that means either ( doing propulsive capture at Mars and Earth return  ( => much much more propellant => much much more mass to launch ) or developing new reusable thermal protection systems to aerocapture ) and new in orbit refueling and ( zero boil-off or using store-able propellant ( =>  much ore propellant => much more launch mass) ). It's a long term very expensive wide open trade space. It's not clear that it's 'a better investment' than a minimal mission, it depends what you are optimizing for - i.e. not if you are optimizing for something that can be done soon.

I try to minimize costs by using as far as possible only existing heritage tech.

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4 hours ago, kerbiloid said:

A fly-by photo of the coal-black midnight Mars on a black sky backround.
(Because a fly-by ship will turn around the Mars above its night side).

A fly-by photo of the milky-white noon Venus clouds on a black sky backround.
(Because a fly-by ship will turn around the Venus above its subsolar side).

Passing the night side is why I said a 'crescent Mars', cause you'll be barreling into a 'waning Mars' before you pass the night side. I've not looked at 'starlight cameras' or if you'd get any 'evocative' lighting from the moons, but a big bright crescent would do nicely. Same deal for Venus but waxing, for sure it's a lot less feature-full - on the other hand from Earth you cannot miss it every day at dawn or dusk and think 'did we really throw someone to that and catch them again'. 

9 hours ago, DBowman said:

A a selfie of a helmeted face with crescent Mars and an Earth star could be as iconic as the 'earthrise' photo.

 

5 hours ago, Nibb31 said:

If your two ships are identical, then they both have the same failure modes. If one has a technical problem, then the other is likely to have the same problem at one point, and you end up with two stranded ships and crews instead of one.

It's a fun challenge trade off to think about; if you use redundant copies you are exposed to 'same failure modes' but can 'share spares' ( 4 copies need only 2 sets of spares to be just as safe ) but if you use heterogeneous redundancy you are safe from 'same failure modes' but cannot share spares. The professionals have terms of art for these two kinds of redundancy (which I forget just now).

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1 hour ago, DBowman said:

The Curiosity Rover program was 1.6 B 2009 USD, the space craft (rover and EDL I guess) was 0.94 B of that (plus maybe some of the 'other costs' were s/w etc for that), launch costs are on the way down - but mission design can blow the lauch mass requirements way up again. If you are building 'many' identical / related craft you could amortize the 'space craft develop' subset of the 0.94 B - as long as you have a lot more total money to spend. I'm all up for reusable craft to amortize construction over multiple trips; but that means either ( doing propulsive capture at Mars and Earth return  ( => much much more propellant => much much more mass to launch ) or developing new reusable thermal protection systems to aerocapture ) and new in orbit refueling and ( zero boil-off or using store-able propellant ( =>  much ore propellant => much more launch mass) ). It's a long term very expensive wide open trade space. It's not clear that it's 'a better investment' than a minimal mission, it depends what you are optimizing for - i.e. not if you are optimizing for something that can be done soon.

I try to minimize costs by using as far as possible only existing heritage tech.

These could be done using 1960s technology. We could've geared for a Mars mission then, and we can now. Minimizing the mission may not save much money, especially if we look at von Brauns 1969 Mars mission proposal. It's quite doable, even now.

It's a better Investment because a minimal mission requires you to build a new craft for every mission.

Edited by Bill Phil
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11 hours ago, DBowman said:

I love '(hum)man against the odds' stories; Shackleton & Douglas Mawson in the Antarctic,  and Reihhold Messner's solo Everest without supplemental oxygen (overturning accepted wisdom and practice on two counts).

Like the last guy who died this last month crossing the antarctic at foot and he died like 20 km before reach its destiny :S
One of the old books I have is from Bernard Moitessier.

11 hours ago, DBowman said:

I think the radiation risk is not too bad. From my reading so far it seems like the dose received will be more or less in line with NASAs life time limit for a career astronaut (which is 4x a nuclear plant worker lifetime dose), I think I recall they are more conservative than the Europeans. I haven't done a detailed investigation yet. After 500 days in the can the astronaut probably wont mind that it was a once in a lifetime deal.

180 days transit to mars is equivalent to 300msv, a nuclear worker only has allow it 50msv by year, so your 500 days is close to 15 times the nuclear worker limit (that is already high), then you need to add the risk for solar flares.. that in a 500 day period..  is not so weird to happen..  That case is equal to a fatal dose.
All that and you dont let the astronaut to put a foot in mars (where is more protected than in space due planet rotation) or venus cloud which dose is zero. 
If someone will put his life or health in risk..  at least let them make history. It does not matter if it will cost 4 times more (if you were cost efficient in the first place)

11 hours ago, DBowman said:

I don't think the loss of one guy would kill the space program, though I think you are right that it would come up if the flyby lost the crew.

It should not if it is properly handled in the media.
You need to be success to make people understand that this is a huge achievement that only comes under huge risks, that is in human nature to accept those risk in order to go where nobody were before.
We understood that just 45 years back and over the whole human history..  People in history made trips on odds so low that it does not have even comparison with any space travel.

11 hours ago, DBowman said:

Redundancy can be very expensive. Imagine a Minimal Multiply Redundant flyby:

  • 2x Each craft has to be double volume, consumables, with double LS machinery 
  • 2x2x That larger craft might kick the mass over the 'direct launch' threshold doubling the launches per vehicle and adding a docking failure point and maybe shifting the transfer propellant to non cryo => increasing the mass again...
  • 2x3x maybe adding another launch and docking for the transfer propellant
  • 2x3x2x Then we need two of these, and they have to fly in formation or docked to be usefully redundant

So just one back up makes the mission at least ten times as expensive and much more complex, with many more failure points. 

Many of the big spending programs have plenty of scope to kill the crew. Small is simple, simple is safe, worst case you don't loose too much/many.

You need to apply redundancy in things as electronics because radiation can convert a bit between 1 or 0, this give you errors and possible crash.
But there is no chance that your spaceship will break on half or something similar to need another one..  You look redundancy in those possible errors that might happen and there are cheap to solve with redundancy.
But in case a ISRU ship that it will land before a identical manned ship arrive.. in that case redundancy has a lot of sense. Because the most of the cost is in development, once you have a design you can made 3 without adding much to the cost. It also gives you the chance to test that design in transit, landing and as ISRU before you sent the astronauts.

12 hours ago, Bill Phil said:

Here's my question: Why go minimal at all? Yeah, I understand cost issues and other aspects, but you might as well go full out, especially since it might only have a total cost of 1 trillion USD. And current global spending on space is about 70 billion, so, over enough time and with enough collaboration, it could be done. GWP is over 70 trillion USD. And it might not even cost a trillion, especially with advanced tech and design processes, plus a huge industry and a huge global economy. And if it's full out, we might even get a bigger space industry that could stay that way...

If you think about trillons, is because you dont have much idea of all the things you can buy with just a million (if you take care of your money).
The planned building "Changsha" from china, will be tall as burj khalifa but much bigger, it will have close to 20000 residents and it will cost 1.4billions, before you said that this is a easy task or does not have its risk.. Try to imagine the engineers working in the structure to make it  aerodynamics, earthquake, fire, terrorism proof in addiction with many other issues that are related to accomodate and serve 20000 vertical residents and guarantee its safety.
You are speaking of 1000 billions to develop some ships and props needed for a mars mission who is not using any new tech (literally speaking)    

8 hours ago, Nibb31 said:

Number of patents filed in 2014:

  • Boeing: 911
  • Lockheed Martin: 263
  • ULA: 2
  • SpaceX: 0
  • General Motors: 1470
  • Honda: 1099
  • Ford: 804
  • Tesla: 61

Who says they are? Again, Musk doesn't publish any financial records because he doesn't have to, so it's hard to say how well they are actually performing compared to the rest of the industry.

http://www.businessinsider.com/elon-musk-patents-2012-11

All big companies buy any kind of patent just to store them and suing other companies who try something similar. 
Again.. you are trying to said that spacex is not a innovative company..   I dont think to waste more time in this..   is all on you...  

8 hours ago, Nibb31 said:

You really have no idea what you're talking about. Test campaigns costs a lot of money. In fact, if you have ever worked in any kind of industry, you'd know that it typically costs more that 50% of the actual production work. I work in software, and we actually have as many quality engineers as we have developers. The same is true for most advanced manufacturing facility. Environmental testing costs even more, because it requires specialized facilities.

Who are you trying to convince?  We had this discussion many times and I prove you wrong..  with argument, logic, predictions (who many was already confirmed and the rest all are in good track) and with reality.  All the things you said and you still cannot answer how spacex does it? 
You always had the same posture against everything, the rule is:  "if is new and nobody is using that already, it must be because is not good.. so that will be my opinion the 100% of the time"
It will kill you to think on your own for once, analysing a single case base on your knowledge and possibilities? 
If I said that NASA is totally cost-inefficient in everything they do, and I prove it with logic and other examples of companies doing the same thing.    Then you go out and said that is how is done because I was in a similar position and that is what it cost..  No sure what you want to accomplish with that argument.

8 hours ago, Nibb31 said:

When you're in a 15 year project, you can't afford to switch technology every 3 years and start over again. If you do that, you're never going to launch

Any good company can make those "15 year projects" -hello james webb telescope..   in 4 years at 1/10 of the cost.  So there is no need for that.

8 hours ago, Nibb31 said:

I explained why: it uses general purpose flight computers that each run a specialized task, but are capable of running the task of another computer. You don't just carry along spare computers as dead weight for redundancy. They are interchangeable. And because they each only do limited tasks, they can be smaller and use less power than your average PC. And the software is simpler too, which means that it doesn't need to be rewritten and recertified.

Source?   so if one fail..  then you need to wait until the other makes the same operation from the begining?   So the computer that is measuring the landing thrust power gets a 0-1 swap episode which give you error and then other computer needs to start that program and continue from there.. that is when the software crash... literally due surface. 

8 hours ago, Nibb31 said:

It's more like RAID5 than RAID1 (look it up please). You are suggesting RAID1 (duplicate everything), the industry uses RAID5 or 6 (spread the load over multiple assets with built-in redundancy).

When I said you need to duplicate everything?   The electrolysis machine is something that needs redundancy..  In the ISS they have 3, if it will be better designed from the begining they would be using 3 PEM devices that weights 4 times less (each one), they work at better efficiency and with less issues, they need less chemical reposition. 

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2 hours ago, AngelLestat said:

All big companies buy any kind of patent just to store them and suing other companies who try something similar. 
Again.. you are trying to said that spacex is not a innovative company..   I dont think to waste more time in this..   is all on you...  

No, I'm trying to say that the other companies are at least as innovative as SpaceX. They are not idiots like you try to portray them.

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Who are you trying to convince?  We had this discussion many times and I prove you wrong..  with argument, logic, predictions (who many was already confirmed and the rest all are in good track) and with reality.  All the things you said and you still cannot answer how spacex does it? 

I've given up trying to convince you. I'd just like to avoid some newcomers to this forum from drinking the SpaceX fanboy Koolaid. It's way too easy to portray one company as having all the answers and the others to be idiots. Try getting an engineering degree and a few decades of experience in the business and then you might be qualified to issue a judgement on how an entire industry operates.

How SpaceX does what? SpaceX is cheaper than others for several reasons:

  • They hire mostly starry eyed newbie engineers who are cheap and willing to work 60 hour weeks.
  • They don't have more experienced workers that require higher wages, nor do they have pensions.
  • They have a leaner organization with less levels and less history.
  • They make as much as they can in-house and cutting out traditional aerospace suppliers.
  • They use parts that aren't necessarily aerospace-certified (like the helium tank struts on CRS-7).

I suppose that all makes a good business strategy. Other companies have larger structures that result from decades of mergers and past projects. The result is higher overhead and less agility. They work in a different environment, with a different history, different customers, different requirements, different rules and procedures, but they are not stupid.

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If I said that NASA is totally cost-inefficient in everything they do, and I prove it with logic and other examples of companies doing the same thing.    Then you go out and said that is how is done because I was in a similar position and that is what it cost..  No sure what you want to accomplish with that argument.

Any good company can make those "15 year projects" -hello james webb telescope..   in 4 years at 1/10 of the cost.  So there is no need for that.

JWST in 4 years? You're just pulling stuff out of your rear end again. You simply have no idea how complex something like JWST actually is. It's not something that you can build in your garage. 

Sure, it's been a poorly run project in terms of cost management. That doesn't prove that "NASA is cost-inefficient in everything they do", nor can you provide an example of "companies doing the same thing", because most of what NASA does, nobody else does. If NASA wasn't around, there would be no space industry in general and no SpaceX in particular, so quit the NASA-bashing.

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Source?   so if one fail..  then you need to wait until the other makes the same operation from the begining?   So the computer that is measuring the landing thrust power gets a 0-1 swap episode which give you error and then other computer needs to start that program and continue from there.. that is when the software crash... literally due surface. 

From your arguments bashing thousands of real aerospace engineers and scientists, you clearly have no idea how computers work, how industries work, how R&D activities work, how project management works, how quality assurance works, how politics or economics work. I don't know what you're background is, but I can tell it isn't engineering, let alone aerospace engineering.

True wisdom is knowing what you don't know.

 

Edited by Nibb31
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5 hours ago, Bill Phil said:

It's a better Investment because a minimal mission requires you to build a new craft for every mission.

My minimal one man flyby looks like it could use existing Falcon Heavy on a Soyuz orbiter, 0.1B USD craft cost + launch cost (I know there is a little more craft cost since it needs some 'extra module for LS, e, & thermal regulation), I imagine that is less than the design studies for the kind of missions you have in mind.

Edited by DBowman
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25 minutes ago, AngelLestat said:

Like the last guy who died this last month crossing the antarctic at foot and he died like 20 km before reach its destiny :S

...

It should not if it is properly handled in the media. You need to be success to make people understand that this is a huge achievement that only comes under huge risks, that is in human nature to accept those risk in order to go where nobody were before. We understood that just 45 years back and over the whole human history..  People in history made trips on odds so low that it does not have even comparison with any space travel.

Yep, I don't see anyone shutting down mountain climbing which also kills a lot of people just doing 'personal challenges'.

29 minutes ago, AngelLestat said:

a nuclear worker only has allow it 50msv by year, so your 500 days is close to 15 times the nuclear worker limit (that is already high), then you need to add the risk for solar flares.. that in a 500 day period..  is not so weird to happen..  That case is equal to a fatal dose.

You are mixing up annual limit and lifetime limit, it's higher than their annual but similar to lifetime. Re solar flares I've designed in a 'storm shelter' with what should be adequate protection, I can increase it more if there is free mass.

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^^Also, instead of him just making stuff up regarding occupational exposures, you can just look at NASA's own policy on the subject. they have career dosage guidelines based on age and sex of the astronauts posted, and their Mars mission planning includes this (both in design, and candidate selection should it ever actually happen). Basically after Mars you get a desk job.

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13 hours ago, Nibb31 said:

Test campaigns costs a lot of money. In fact, if you have ever worked in any kind of industry, you'd know that it typically costs more that 50% of the actual production work. I work in software, and we actually have as many quality engineers as we have developers. The same is true for most advanced manufacturing facility. Environmental testing costs even more, because it requires specialized facilities.

Quality is expensive. Aerospace quality is even more expensive.

I have similar s/w dev experience and if you counted QA group and the 'baked into the code' unit and integration tests it's probably the dominant cost - proving you've done it right and that it stays right when you change what you think is unrelated stuff is expensive. Often the 'test harness' is more time consuming than the code, analogous to 'specialized facilities' (lets leave it in vacuum for two years). The raw time is also a killer; if you have a 2 year flight time I don't think anyone is going to be happy running the LS tests for much less time...

 

Just now, tater said:

you can just look at NASA's own policy on the subject

I'm pretty much following NASA and ESA guidelines, aiming to hit the most protective one if possible. NASA's solar radiation protection standard wants more mass/cm2 so the joke is (apparently) to save mass by sending ESA astronauts.

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2 hours ago, DBowman said:

My minimal one man flyby looks like it could use existing Falcon Heavy on a Soyuz orbiter, 0.1B USD craft cost + launch cost (I know there is a little more craft cost since it needs some 'extra module for LS, e, & thermal regulation), I imagine that is less than the design studies for the kind of missions you have in mind.

That's onl a flyby, no landings.

A flyby is easy. Even going all out. But landing and coming back is much harder.

I was actually basing my estimations on von Brauns expedition plan from 1952, where each craft was a few thousand metric tons. And there were ten of them... 

But, using his later design from 1956 we can get about 120 billion using the same estimation method. And we still get a Mars landing. For the price of the entire Apollo program. And probably a reusable transfer vehicle, for more missions.

Now, we can lower that cost further. 2 1700 metric ton vehicles is a bit impossible, and that mass can be lowered to a few hundred, with really smart designs. Lowering costs enormously.

3 hours ago, AngelLestat said:

Like the last guy who died this last month crossing the antarctic at foot and he died like 20 km before reach its destiny :S
One of the old books I have is from Bernard Moitessier.

180 days transit to mars is equivalent to 300msv, a nuclear worker only has allow it 50msv by year, so your 500 days is close to 15 times the nuclear worker limit (that is already high), then you need to add the risk for solar flares.. that in a 500 day period..  is not so weird to happen..  That case is equal to a fatal dose.
All that and you dont let the astronaut to put a foot in mars (where is more protected than in space due planet rotation) or venus cloud which dose is zero. 
If someone will put his life or health in risk..  at least let them make history. It does not matter if it will cost 4 times more (if you were cost efficient in the first place)

It should not if it is properly handled in the media.
You need to be success to make people understand that this is a huge achievement that only comes under huge risks, that is in human nature to accept those risk in order to go where nobody were before.
We understood that just 45 years back and over the whole human history..  People in history made trips on odds so low that it does not have even comparison with any space travel.

You need to apply redundancy in things as electronics because radiation can convert a bit between 1 or 0, this give you errors and possible crash.
But there is no chance that your spaceship will break on half or something similar to need another one..  You look redundancy in those possible errors that might happen and there are cheap to solve with redundancy.
But in case a ISRU ship that it will land before a identical manned ship arrive.. in that case redundancy has a lot of sense. Because the most of the cost is in development, once you have a design you can made 3 without adding much to the cost. It also gives you the chance to test that design in transit, landing and as ISRU before you sent the astronauts.

If you think about trillons, is because you dont have much idea of all the things you can buy with just a million (if you take care of your money).
The planned building "Changsha" from china, will be tall as burj khalifa but much bigger, it will have close to 20000 residents and it will cost 1.4billions, before you said that this is a easy task or does not have its risk.. Try to imagine the engineers working in the structure to make it  aerodynamics, earthquake, fire, terrorism proof in addiction with many other issues that are related to accomodate and serve 20000 vertical residents and guarantee its safety.
You are speaking of 1000 billions to develop some ships and props needed for a mars mission who is not using any new tech (literally speaking)    

http://www.businessinsider.com/elon-musk-patents-2012-11

All big companies buy any kind of patent just to store them and suing other companies who try something similar. 
Again.. you are trying to said that spacex is not a innovative company..   I dont think to waste more time in this..   is all on you...  

Who are you trying to convince?  We had this discussion many times and I prove you wrong..  with argument, logic, predictions (who many was already confirmed and the rest all are in good track) and with reality.  All the things you said and you still cannot answer how spacex does it? 
You always had the same posture against everything, the rule is:  "if is new and nobody is using that already, it must be because is not good.. so that will be my opinion the 100% of the time"
It will kill you to think on your own for once, analysing a single case base on your knowledge and possibilities? 
If I said that NASA is totally cost-inefficient in everything they do, and I prove it with logic and other examples of companies doing the same thing.    Then you go out and said that is how is done because I was in a similar position and that is what it cost..  No sure what you want to accomplish with that argument.

Any good company can make those "15 year projects" -hello james webb telescope..   in 4 years at 1/10 of the cost.  So there is no need for that.

Source?   so if one fail..  then you need to wait until the other makes the same operation from the begining?   So the computer that is measuring the landing thrust power gets a 0-1 swap episode which give you error and then other computer needs to start that program and continue from there.. that is when the software crash... literally due surface. 

When I said you need to duplicate everything?   The electrolysis machine is something that needs redundancy..  In the ISS they have 3, if it will be better designed from the begining they would be using 3 PEM devices that weights 4 times less (each one), they work at better efficiency and with less issues, they need less chemical reposition. 

It's trillions due to the huge overhead and launch costs. Material costs? Almost nil compared to total.

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On February 7, 2016 at 11:48 AM, AngelLestat said:

Fly by to the moon may have sense..    but fly by to mars or venus or both..  sounds like a sick joke on the astronauts, all that dose of radiation, months and months of travel with psychological issues, just to see mars 1 day through the windows and stay in that can all the way back..  if the astronaut reach earth again.. can be a nice guy as dr mann in interstellar.

 Havoc mission lasted 440 days, 1 month in orbit, 1 month in the clouds.
In case you want to reduce the radiation doses you need to spent a lot more time in venus 1.2 years.
Transit: 112 days go, 96 days back.

 

Calling spacex: "a no innovative company.." is like calling Tesla: "a no innovative inventor".

why spacex is in the top of the space industry then?   

Sorry, but I never said that you should no test your things...  I just said that you should use the top of the technology every time you can. Because when you not do that, all cost skyrockets.
Those test cost nothing, the test that cost money is things you test in space, crash test, or anything that requires launch things to high altitude. The software development is the most expensive in everything related to electronics.

They are just normal laptops with normal components..  the only important there was the vibration test that depends on the quality of the manufacture company. They use win7, so they are new compared to all the things that NASA use.
One of those problems is because when they start a project, they already start using old tech, then after 10 or 15 years of delay in turtle development speed, their tech has 15 or 20 years old, which increase a lot the cost because nobody remember how that thing work and you dont have support because that thing is no in the market anymore.
Also.. many other techs appear in that time which make your whole design totally outdated and pointless vs new approaches.   

Why orion does then?

 

This topic is being derail, and for one weird reason according to one moderator.. is always my fault..
I explain this already.. the only thing that matters is deterioration (that can be tested and even find some shielding chosen its location), and Single event upsets that are solved with software or connecting devices in parallel. 

How much money and software development will need?  
You can not run any modern app in case you found that some may be usefull.  

You can design anything you want.. but if it cost more than the people is welling to pay.. then you stay in home.
That is reality.

Manned flybys are only good for manned stunt flights/test flights for a larger planetary program, just like Apollo 8 was for the Lunar program. People have proposed using it as a standalone, but the development costs aren't worth it by itself.

A long-time manned mission to Venus is a bad idea- for the first missions. I agree we should pursue them- but in evoltionary steps. The amount of risk of a year on Venus is likely worse then spending that in transit around the Sun- something we aremuch more familiar with, minus the radiation.

Being "innovative"and on the top of the space industry have nothing to do with each other. There's not really much innovative about the Ariane 5, and that was (and still is) at the top of the heavy-lift industry. The Pegasus, N1, and even the Shuttle were a lot more innovative-and are not exactly successful.

SpaceX got successful bevcause it was able to organise itself in a way that was cheaper than what everyone else was doing.

Tests DO cost a lot of money. Neither is being innovative for the sake of being innovative. A rocket powered by Al/Lox is innovative- but it will never be done (except for lunar landers) due to lower performance. the SSME is very innovative- but also is the most expensive rocket engine in existance. And a vast amount of time building rockets is testing- and time=money.

Generally, few use things like Windows 7 for important compnsents as it is VERY complex- it's very easy to miss something- and simpler things are easier to debug. Space doesn't need the latest tech- it needs reliability and functionality.

yes the thread being derailed is your fault.

On February 7, 2016 at 0:37 PM, DBowman said:

500 days is not even close to current duration records for solo yachtsmen, time in the can is the least of your problems - read some books, do some blogging ...

Being on Earth really helps with the lonliness aspect though- you're even more lonely as a solo astronaut, with almost nothing familiar to your home and nothing but the lights on the computers and the stars to look at.

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On February 7, 2016 at 11:48 AM, AngelLestat said:

Fly by to the moon may have sense..    but fly by to mars or venus or both..  sounds like a sick joke on the astronauts, all that dose of radiation, months and months of travel with psychological issues, just to see mars 1 day through the windows and stay in that can all the way back..  if the astronaut reach earth again.. can be a nice guy as dr mann in interstellar.

 Havoc mission lasted 440 days, 1 month in orbit, 1 month in the clouds.
In case you want to reduce the radiation doses you need to spent a lot more time in venus 1.2 years.
Transit: 112 days go, 96 days back.

 

Calling spacex: "a no innovative company.." is like calling Tesla: "a no innovative inventor".

why spacex is in the top of the space industry then?   

Sorry, but I never said that you should no test your things...  I just said that you should use the top of the technology every time you can. Because when you not do that, all cost skyrockets.
Those test cost nothing, the test that cost money is things you test in space, crash test, or anything that requires launch things to high altitude. The software development is the most expensive in everything related to electronics.

They are just normal laptops with normal components..  the only important there was the vibration test that depends on the quality of the manufacture company. They use win7, so they are new compared to all the things that NASA use.
One of those problems is because when they start a project, they already start using old tech, then after 10 or 15 years of delay in turtle development speed, their tech has 15 or 20 years old, which increase a lot the cost because nobody remember how that thing work and you dont have support because that thing is no in the market anymore.
Also.. many other techs appear in that time which make your whole design totally outdated and pointless vs new approaches.   

Why orion does then?

 

This topic is being derail, and for one weird reason according to one moderator.. is always my fault..
I explain this already.. the only thing that matters is deterioration (that can be tested and even find some shielding chosen its location), and Single event upsets that are solved with software or connecting devices in parallel. 

How much money and software development will need?  
You can not run any modern app in case you found that some may be usefull.  

You can design anything you want.. but if it cost more than the people is welling to pay.. then you stay in home.
That is reality.

Manned flybys are only good for manned stunt flights/test flights for a larger planetary program, just like Apollo 8 was for the Lunar program. People have proposed using it as a standalone, but the development costs aren't worth it by itself.

A long-time manned mission to Venus is a bad idea- for the first missions. I agree we should pursue them- but in evoltionary steps. The amount of risk of a year on Venus is likely worse then spending that in transit around the Sun- something we aremuch more familiar with, minus the radiation.

Being "innovative"and on the top of the space industry have nothing to do with each other. There's not really much innovative about the Ariane 5, and that was (and still is) at the top of the heavy-lift industry. The Pegasus, N1, and even the Shuttle were a lot more innovative-and are not exactly successful.

Tests DO cost a lot of money. Neither is being innovative for the sake of being innovative. A rocket powered by Al/Lox is innovative- but it will never be done (except for lunar landers) due to lower performance. the SSME is very innovative- but also is the most expensive rocket engine in existance. And a vast amount of time building rockets is testing- and time=money.

 

On February 7, 2016 at 0:37 PM, DBowman said:

500 days is not even close to current duration records for solo yachtsmen, time in the can is the least of your problems - read some books, do some blogging ...

Being on Earth really helps with the lonliness aspect though- you're even more lonely as a solo astronaut, with almost nothing familiar to your home and nothing but the lights on the computers and the stars to look at.

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4 hours ago, Nibb31 said:

No, I'm trying to say that the other companies are at least as innovative as SpaceX. They are not idiots like you try to portray them.

Not me.. Spacex is making them look like idiots;)
Try to think a bit better your next answer, you are fighting against reality here.

Quote

I've given up trying to convince you. I'd just like to avoid some newcomers to this forum from drinking the SpaceX fanboy Koolaid. It's way too easy to portray one company as having all the answers and the others to be idiots. Try getting an engineering degree and a few decades of experience in the business and then you might be qualified to issue a judgement on how an entire industry operates.

You already did that koolaid joke.. where is your innovation?
I am systems engineer, you should remember that after you try to explain me guides of project managements.
Also, after so many times that I prove you wrong with direct evidence (in case you don't want to count all the others), I should receive a bit more of love from you..  in the case you like to get rid of wrong concepts of course.

Quote

Sure, it's been a poorly run project in terms of cost management. That doesn't prove that "NASA is cost-inefficient in everything they do", nor can you provide an example of "companies doing the same thing", because most of what NASA does, nobody else does. If NASA wasn't around, there would be no space industry in general and no SpaceX in particular, so quit the NASA-bashing.

You want to said if nasa was not around.. then another agency or company will get that money and made a better use of that money.  Dont get me wrong.. I dont hate those guys.. I love them.   I love what they represent.. That scientific aspect..  But sorry, with the pass of the years.. they lose the structure and the efficient management to make a good use of that budget. So lately and sadly..  now they are becoming in an obstacle for their same objective.

Quote

you clearly have no idea how computers work, how industries work, how R&D activities work, how project management works, how quality assurance works, how politics or economics work. I don't know what you're background is, but I can tell it isn't engineering, let alone aerospace engineering.

I dont..??  tell me what is the cost of working with old software and hardware..  I am listening...
The first thing that I am telling since I comment in this topic.  Trying to help to DBowman to understand that technology is not the enemy, but you started to said the opposite and getting off topic :S  
Also.. You said that I don't understand politics or economics?

-Remember the skylon discussion about if it has economic sense to have those launch cost?  
Well ESA did a big economic study and it was proved that it has economic sense.
-Remember when I predict a big increase in launch demand with cheap satts made with modern production lines with new business cases, and you said that was impossible because I did not knew nothing on how those projects are managed..  Half year later.. constellations boom news over all the place.  
-Remember when I predict Airships and quadrotors transporting cargo and you said that quadrotors never will get FAA approval and that airships (if they appear) they will have a very small niche?
Well many drones already have faa approval for those works and airship production start in 4 or 5 different companies and europe is already creating the logistic for this kind of vehicles.
-When I said that venus was easier and a better case, and almost one year after NASA made the concept mission and said that it will be easier than a trip to mars..
You now that I can continue with examples.. but you get what I mean..  

3 hours ago, DBowman said:

You are mixing up annual limit and lifetime limit, it's higher than their annual but similar to lifetime. Re solar flares I've designed in a 'storm shelter' with what should be adequate protection, I can increase it more if there is free mass.

No I am not. 
Real data from the curiosity over its transit time.
http://www.space.com/24731-mars-radiation-curiosity-rover.html

180 days = 300msv, this mean that your 500 days transit trip will be equal to 833msv, if we divide by the max dose than a nuclear worker can be exposed by year /50 --> then is equal to 16,7 times more than a nuclear worker.
But I round the number in 15 because 500 days is higher than 1 year.
 

2 hours ago, tater said:

^^Also, instead of him just making stuff up regarding occupational exposures, you can just look at NASA's own policy on the subject. they have career dosage guidelines based on age and sex of the astronauts posted, and their Mars mission planning includes this (both in design, and candidate selection should it ever actually happen). Basically after Mars you get a desk job.

Read the above answer.. you should check any info provided for me.. I dont mistake often.. and If I do.. I will apology in no time. 

Also that does not include solar flares occurrences, it may happen.

1 hour ago, Bill Phil said:

It's trillions due to the huge overhead and launch costs. Material costs? Almost nil compared to total.

I guess we should wait and see what would be the spacex cost for a trip to mars with spacex launcher, capsule and other things designed for them to make fuel and resources in mars.
The design will be shown this year.. we will need to wait at least some years more to have a cost estimation.
Or you are betting that we will use SLS and Orion to go to mars?   It might work for moon, asteroids or even Venus.. But I cant imagine they will use SLS and Orion for mars.

Edited by AngelLestat
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4 minutes ago, AngelLestat said:

Not me.. Spacex is making them look like idiots;)
Try to think a bit better your next answer, you are fighting against reality here.

You already did that koolaid joke.. where is your innovation?
I am systems engineer, you should remember that after you try to explain me guides of project managements.
Also, after so many times that I prove you wrong with direct evidence (in case you don't want to count all the others), I should receive a bit more of love from you..  in the case you like to get rid of wrong concepts of course.

You want to said if nasa was not around.. then another agency or company will get that money and made a better use of that money.  Dont get me wrong.. I dont hate those guys.. I love them.   I love what they represent.. That scientific aspect..  But sorry, with the pass of the years.. they lose the structure and the efficient management to make a good use of that budget. So lately and sadly..  now they are becoming in an obstacle for their same objective.

I dont..??  tell me what is the cost of working with old software and hardware..  I am listening...
The first thing that I am telling since I comment in this topic.  Trying to help to DBowman to understand that technology is not the enemy, but you started to said the opposite and getting off topic :S  
Also.. You said that I don't understand politics or economics?

-Remember the skylon discussion about if it has economic sense to have those launch cost?  
Well ESA did a big economic study and it was proved that it has economic sense.
-Remember when I predict a big increase in launch demand with cheap satts made with modern production lines with new business cases, and you said that was impossible because I did not knew nothing on how those projects are managed..  Half year later.. constellations boom news over all the place.  
-Remember when I predict Airships and quadrotors transporting cargo and you said that quadrotors never will get FAA approval and that airships (if they appear) they will have a very small niche?
Well many drones already have faa approval for those works and airship production start in 4 or 5 different companies and europe is already creating the logistic for this kind of vehicles.
-When I said that venus was easier and a better case, and almost one year after NASA made the concept mission and said that it will be easier than a trip to mars..
You now that I can continue with examples.. but you get what I mean..  

No I am not. 
Real data from the curiosity over its transit time.
http://www.space.com/24731-mars-radiation-curiosity-rover.html

180 days = 300msv, this mean that your 500 days transit trip will be equal to 833msv, if we divide by the max dose than a nuclear worker can be exposed by year /50 --> then is equal to 16,7 times more than a nuclear worker.
But I round the number in 15 because 500 days is higher than 1 year.
 

Read the above answer.. you should check any info provided for me.. I dont mistake often.. and If I do.. I will apology in no time. 

Also that does not include solar flares occurrences, it may happen.

I guess we should wait and see what would be the spacex cost for a trip to mars with spacex launcher, capsule and other things designed for them to make fuel and resources in mars.
The design will be shown this year.. we will need to wait at least some years more to have a cost estimation.
Or you are beating that we will use SLS and Orion to go to mars?   It might work for moon, asteroids or even Venus.. But I cant imagine they will use SLS and Orion for mars.

I'm using von Brauns proposal from 52...........

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21 hours ago, DBowman said:

...but what kind of stunt is it? going over Niagara Falls in a barrel or flying across the Pacific the first time? even a pure stunt can usefully inspire - who comes back from watching tumblers and trapeze artists and doesn't just for a moment consider 'what would that be like?', 'what does that take?' - at the least you get a renewed respect for the unlikely capability of people.

My initial thoughts on Inspiration Mars were 'pointless stunt', but on thinking about it I changed my mind:

  • This small and simple enough to be fundable. NASA DRAs are 35 Billion USD. Even Inspiration Mars got caught up in scope creep with multiple lifts and on orbit assembly, 2.5 Billion USD. A minimal direct one shot is much cheaper, Falcon Heavy + a Soyuz is 0.1 Billion USD ( plus more costs I know, and Soyuz has the H2O2 problem ). Small simple and done would be better than large useful and never done.
  • The long duration medical data is pure science useful, and manned space useful. It's not enough to motivate the trip, it's not the cheapest way to get the data, but if the trip was on it would be criminal not to gather the data and it must have a dollar value somewhat less than getting it from ISS (because after 15 year we seem not to to have bothered). 
  • If you have real plans for a manned Mars program (Elon Musk maybe, NASA maybe) then it sure makes sense to do flybys. You can shake out parts of the tech stack, build experience with the operating procedures, etc - you can do this while still grappling with the real hard problems of aerocapture (do it!), Mars EDL, and ascent. All the reasons they did the Apollo flyby.
  • Long duration flybys could conceivably use people as a 'force multiplier' for autonomous components. You can throw a craft into a companion orbit to Mars so they do an 'extended flyby' where they spend months within a few light seconds for Mars, taking 30 mins out of the 'control loop' could greatly increase the flexibility, rate, and amount of data gathering possible from landed elements. Automated systems are getting better and better, but really still not that great and 'man on Earth in the loop' must really slow things down.
  • I think there would be some drama associated with the flyby, e.g. will (did) the maneuver engine fire near Mars to tweak the trajectory for a return, was enough ablator added to the capsule. That kind of ephemeral drama might help sell the idea of doing the flight and maybe get some support dollars, but there is a longer term awe and inspiration factor. A a selfie of a helmeted face with crescent Mars and an Earth star could be as iconic as the 'earthrise' photo. The moon was different after you could look up and think 'we' stood there and ran that dust through our gloved fingers, Mars and Venus will be different after you can look at the first star of evening and think 'we' threw someone close enough to almost touch that and got them back safe.

-I agree, small and simple is best- but you need margins large enough for NASA to accpet it. Putting a crew in a Syouz for several months is a horrible way to get enough margins. I'd feel sorry for the astronaut- barely being able to move for months on end.

-The long duration medical data should only be obtained once we put a simulant mission in Cis-Lunar toredue risk.

-We've pretty much established manned flybys are pointless for science. Yoi can do a lot more with a cheaper flagship orbiter.

-Hail Mary Passes are horrible, as a crew death would be devastating, but you can bet the media will dramatacise it.

20 hours ago, Bill Phil said:

The downside is the lack of redundancy. If the ship breaks, you get a dead crew. And then a dead space program. If you have a huge fleet, and a ship breaks, you can rescue most of the crew.

Then design your ship so it has a low chance of failure.

17 hours ago, Bill Phil said:

...

I was referring to the ultimate return on investment. Not the redundancy. Most of the money for an all out expedition is overhead and launch costs. But once it's in orbit, it's an asset. And if it's capable of going to Mars and back four or five times, along with the rest of the fleet, then it's a better investment than the minimal mission would be.

Heck, if you're real smart about your design you could get the cost down by quite a large margin, with the same returns.

A minimal mars mission is most likely to happen (+ margins) and so that is what we should pursue. And reuse makes no sense unless you have something else to use the stuff you brought back for.

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Solar flares are a problem that all mission planning deals with, even if it's just hiding in a shadowed area of the ship. For most designs, you can simply point the engines radially towards the sun, that's going to put the maximum mass between you and the threat. For cosmic rays, there's nothing to do, really, short of using plastics (inflatables) with low interaction cross-sections to avoid cascades. It;s just a hazard of the job to deal with that. 

http://srag.jsc.nasa.gov/Publications/TM104782/techmemo.htm

https://www.nasa.gov/sites/default/files/files/1_NAC_HEO_SMD_Committee_Mars_Radiation_Intro_2015April7_Final_TAGGED.pdf

TL, DR: NASA accepts that for long missions like Mars they will accept an increased lifetime risk of cancers as a cost of doing the mission.

"Mars Missions May Expose Crews To Levels Of Radiation Beyond Those Permitted By The Current LEO Cancer Risk Limit (≤ 3% REID, 95% C.I.)"

Example given: "If 100 astronauts were exposed to the Mars mission space radiation, in a worst case (95% confidence) 5 to 7 would die of cancer, later in life, attributable to their radiation exposure and their life expectancy would be reduced by an average on the order of 15 years."

 

On the topic of the minimal mission "flyby," I'm still entirely against it, it's a waste of time and money. The science returns are not worth it (and more could be done for far less money by probes), and it's not even good from an excitement/PR value point of view. An orbital flight is another matter, that can have at least some good photo ops, and a reasonable duration mission would allow for real-time control of robotic assets on the surface to leverage what they can do (they can drive substantially faster, for example, and cover more ground). If learning about the medical effects of long duration flight outside LEO is a goal, cislunar is better, IMO. You could also tether a hab and get data on long-term exposure to different g levels. All just a few days from him if there is a problem.

Edited by tater
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Just now, AngelLestat said:

180 days = 300msv, this mean that your 500 days transit trip will be equal to 833msv, if we divide by the max dose than a nuclear worker can be exposed by year /50

'divide by the max dose than a nuclear worker can be exposed by year' you are only calculating how many 'nuclear worker equivalent years' the trip represents - that's kind of meaningless/irrelevant. some NASA doc has astronaut lifetime limits between 1000 msv for a 25 year old female up to 4,000 msv for a 55 year old male. I'd lean toward sending a young female because they could 'carry the torch' for longer afterward (we are loosing all out Moon walkers already) and might be more mediagenic. 

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BTW, regarding radiation safety, it's actually not characterized terribly well for sub-acute exposures as I understand it. For large, single doses, there is some good data (mostly from the Soviets, as they managed to have rather more naval accidents than the USN did). But the "cumulative" nature of lifetime dosing is not at all clear in terms of outcomes.

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23 minutes ago, fredinno said:

Putting a crew in a Syouz for several months is a horrible way to get enough margins. I'd feel sorry for the astronaut- barely being able to move for months on end.

 

33 minutes ago, fredinno said:

Being on Earth really helps with the lonliness aspect though- you're even more lonely as a solo astronaut, with almost nothing familiar to your home and nothing but the lights on the computers and the stars to look at.

Both true / pretty true / things to worry about - but what are you going to do? If the numbers say that's the only way to do it safe, cheap, and soon then you just have to select someone who can manage it. I imagine for the solo sailors the ocean vista could be comforting/interesting. I don't know how the early Antarctic over winter missions coped - e.g. Mawson's hut 18 guys 57 m2 .

The qualities that made someone suit 8.5 m3 might work against their suitability as media representative afterward ... still you never know human variation is wide...

Soyuz has issues, maybe newer craft will be more suitable when they come online, newer launchers have bigger margins.

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1 hour ago, fredinno said:

-I agree, small and simple is best- but you need margins large enough for NASA to accpet it. Putting a crew in a Syouz for several months is a horrible way to get enough margins. I'd feel sorry for the astronaut- barely being able to move for months on end.

-The long duration medical data should only be obtained once we put a simulant mission in Cis-Lunar toredue risk.

-We've pretty much established manned flybys are pointless for science. Yoi can do a lot more with a cheaper flagship orbiter.

-Hail Mary Passes are horrible, as a crew death would be devastating, but you can bet the media will dramatacise it.

Then design your ship so it has a low chance of failure.

A minimal mars mission is most likely to happen (+ margins) and so that is what we should pursue. And reuse makes no sense unless you have something else to use the stuff you brought back for.

The most well designed system can still break.

Also, according to Atkins laws, it's best to not go to any extremes.

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1 hour ago, tater said:

Solar flares are a problem that all mission planning deals with, even if it's just hiding in a shadowed area of the ship. For most designs, you can simply point the engines radially towards the sun, that's going to put the maximum mass between you and the threat. For cosmic rays, there's nothing to do, really, short of using plastics (inflatables) with low interaction cross-sections to avoid cascades. It;s just a hazard of the job to deal with that. 

http://srag.jsc.nasa.gov/Publications/TM104782/techmemo.htm

https://www.nasa.gov/sites/default/files/files/1_NAC_HEO_SMD_Committee_Mars_Radiation_Intro_2015April7_Final_TAGGED.pdf

TL, DR: NASA accepts that for long missions like Mars they will accept an increased lifetime risk of cancers as a cost of doing the mission.

"Mars Missions May Expose Crews To Levels Of Radiation Beyond Those Permitted By The Current LEO Cancer Risk Limit (≤ 3% REID, 95% C.I.)"

Example given: "If 100 astronauts were exposed to the Mars mission space radiation, in a worst case (95% confidence) 5 to 7 would die of cancer, later in life, attributable to their radiation exposure and their life expectancy would be reduced by an average on the order of 15 years."

 

On the topic of the minimal mission "flyby," I'm still entirely against it, it's a waste of time and money. The science returns are not worth it (and more could be done for far less money by probes), and it's not even good from an excitement/PR value point of view. An orbital flight is another matter, that can have at least some good photo ops, and a reasonable duration mission would allow for real-time control of robotic assets on the surface to leverage what they can do (they can drive substantially faster, for example, and cover more ground). If learning about the medical effects of long duration flight outside LEO is a goal, cislunar is better, IMO. You could also tether a hab and get data on long-term exposure to different g levels. All just a few days from him if there is a problem.

You can't just point mass at the Sun for radiation protection, as the Sun's mag. Field distibutes it throughout space. You need a dedicated radiation shelter, surrounded by mass. Provisions may be a bad idea for the trip back.

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