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Mars Beyond Human Landing Achievement?


NeoMorph

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You're not going to see a nuclear reactor in orbit around the Earth. The NERVA engine may have made sense in the time of putting nuclear reactors on airplanes and using nukes to create harbour areas, but not today. However feasible it is technically you have to account for the political aspect and also the immense costs of R&D and testing before that tech would go on a spacecraft. It has not been shown that we need nuclear engines over say solar electric propulsion, which already exists on many a spacecraft and only needs upscaling for human needs.

From engineering point of view, NERVAS are feasible and practical technology refined by over 20 years of research, I wouldn't be surprised if NTR research would be resumed for the mars missions, this technology had still a lot potential for improvements.

About politics issue, what is a problem with launching NTR engines, if You need even more massive nuclear reactor for powering electric propulsion powerful enough to compete with NTR's and chemical rockets.

Electric propulsion are power hogs and You can't go to mars using only solar power.

EDIT_1: VASIMR is not an technology that is going to work soon (if ever), personally I was very disappointed when VASIMR engine get green light for being ISS tested and scrub funding for development of up-sized Hall effect thrusters (Ion engine), what are already flight proven decades ago.

EDIT_2: Anyway, nuclear reactors in space will became reality sooner or later, if we want to get any advantage over chemical rockets for manned missions.

Edited by karolus10
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That is a crude oversimplification at best. It's not just a matter of "just doing it". Science fiction fluff like this, along with space elevators, nuclear engines and warp drives do nothing but distract from getting actual progress made. We can do it with proven hardware and technology. We can go to the Moon and Mars but there's no political will and a general lack of long term planning.

It's hardly "Science fiction fluff". Any long term deep space mission will need to have either lots of exercise equipment or some form of artificial gravity in order for the astronauts to be able to even walk when they reach their destination. Not so much of a problem if they're coming back to Earth from an asteroid or a flyby, as we have medical facilities and the like, but if they landed on Mars for example, it's going to put a damper on the mood if the first step on another planet is swiftly followed by a face-plant.

Also, nuclear engines have been built and ground tested, so they're hardly science fiction as well. I agree with you that space elevators and warp drives are mostly pointless endeavors to focus on currently, as they're technically impossible for now and won't be built for decades, if not centuries.

As for my crude oversimplification of artificial gravity, what else is there to it?

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First of all, we don't know anything about artificial gravity. We don't know if it actually does prevent bone/muscle loss, how much is enough, or if there are any detrimental side-effects. For example, the coriolis effect induced by the spinning might cause more problems than the artificial gravity solves.

We do know that we can reasonable counteract the biological effects of microgravity with bone-less medication and exercice, and we are currently experimenting those solutions.

Until we have actually done some long-term testing in LEO, it would be unwise to commit to a particular artificial gravity design for something as short as 9 month flight.

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First of all, we don't know anything about artificial gravity. We don't know if it actually does prevent bone/muscle loss, how much is enough, or if there are any detrimental side-effects. For example, the coriolis effect induced by the spinning might cause more problems than the artificial gravity solves.

I believe they did some Earth based testing on artificial gravity induced Coriolis effects, and they found that at 2-3rpm the subjects experienced some symptoms but adapted nearly completely after two days. At 5-6rpm some subjects were able to adapt after a few days, but at 10rpm adaptation wasn't possible, even in the least-susceptible subjects (ones who didn't easily get air-sick, like experienced pilots etc.). At 2-3rpm, you would need a 220m long tether to replicate 1g, which is definitely achievable. Look up the Gemini 11 mission as well, they briefly experimented with the idea and produced a tiny amount of artificial gravity.

There are still many things to consider and try and find out their effects, but shouldn't we at least investigate it rather than discard the idea without any serious thought?

Edited by GJames
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From engineering point of view, NERVAS are feasible and practical technology refined by over 20 years of research, I wouldn't be surprised if NTR research would be resumed for the mars missions, this technology had still a lot potential for improvements.

About politics issue, what is a problem with launching NTR engines, if You need even more massive nuclear reactor for powering electric propulsion powerful enough to compete with NTR's and chemical rockets.

Electric propulsion are power hogs and You can't go to mars using only solar power.

EDIT_1: VASIMR is not an technology that is going to work soon (if ever), personally I was very disappointed when VASIMR engine get green light for being ISS tested and scrub funding for development of up-sized Hall effect thrusters (Ion engine), what are already flight proven decades ago.

EDIT_2: Anyway, nuclear reactors in space will became reality sooner or later, if we want to get any advantage over chemical rockets for manned missions.

It doesn't matter. NERVAs are not going to happen because nobody with power and/or money wants it to happen. Meanwhile, chemical and solar electric propulsion is working great and is being used already. I don't understand the obsession with NTR or other pipe dreams when we have current hardware that can be built and used with proper long term planning. You also don't need nuclear reactors to power solar electric propulsion and you can most definitely go to Mars or further away. Have you not heard of Deep Space 1, Dawn or Hayabusa?

Even without SEP, with just chemical rockets we can get to anywhere in the solar system - it'll just take longer. The know-how for that already exists. Why would you waste years and money on something that's just not necessary? Humans haven't been beyond near earth orbit for almost 50 years and nuclear propulsion is not going to make it happen faster. Nobody wants nuclear propulsion to be a thing, stop trying to make it a thing. Effort needs to go toward convincing the powers that be that human exploration of space (beyond what's already been accomplished) is an important priority.

It's hardly "Science fiction fluff". Any long term deep space mission will need to have either lots of exercise equipment or some form of artificial gravity in order for the astronauts to be able to even walk when they reach their destination. Not so much of a problem if they're coming back to Earth from an asteroid or a flyby, as we have medical facilities and the like, but if they landed on Mars for example, it's going to put a damper on the mood if the first step on another planet is swiftly followed by a face-plant.

Also, nuclear engines have been built and ground tested, so they're hardly science fiction as well. I agree with you that space elevators and warp drives are mostly pointless endeavors to focus on currently, as they're technically impossible for now and won't be built for decades, if not centuries.

As for my crude oversimplification of artificial gravity, what else is there to it?

It is not proven fact that you need artificial gravity for long stays in space. Temporary bone loss can be mitigated with diet and exercise (some people may even have a genetic advantage in this, because the effects vary from astronaut to astronaut).

I believe they did some Earth based testing on artificial gravity induced Coriolis effects, and they found that at 2-3rpm the subjects experienced some symptoms but adapted nearly completely after two days. At 5-6rpm some subjects were able to adapt after a few days, but at 10rpm adaptation wasn't possible, even in the least-susceptible subjects (ones who didn't easily get air-sick, like experienced pilots etc.).

There are still many things to consider and try and find out their effects, but shouldn't we at least investigate it rather than discard the idea without any serious thought?

[citation needed]

Space station with full size Centrifuge (after ISS) and ISS centrifuge demonstrator can allow prove this technology (experiment platform, not for people).

<snip>

I don't think you two understand that this would be another budget line item. NASA operates with finite resources; finite numbers of people and money to use on projects like these. Real world space programs are not Kerbal Space Program. Do you have any idea how many billions of dollars this would cost? Then, many years and billions of dollars later when the experiments are done, even if it's entirely positive and is shown to work, untold billions and years have to be spent working them into spacecraft operations and hardware. All that for artificial gravity, when a treadmill has been shown to work just fine. All that for nuclear propulsion, when we've used chemical propulsion since the dawn of manned flight and solar electric proulsion for two decades.

Edited by Borklund
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Can't cite the source, but I remember reading somewhere along the lines with what GJames said about the extreme motion sickness when they approached the rpms needed for 1g. If you google it there are many articles, don't feel like re-reading to verify. But artificial gravity isn't required for a trip to Mars anyways.

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It doesn't matter. NERVAs are not going to happen because nobody with power and/or money wants it to happen. Meanwhile, chemical and solar electric propulsion is working great and is being used already. I don't understand the obsession with NTR or other pipe dreams when we have current hardware that can be built and used with proper long term planning. You also don't need nuclear reactors to power solar electric propulsion and you can most definitely go to Mars or further away. Have you not heard of Deep Space 1, Dawn or Hayabusa?

Main problem is that Solar electric propulsion powerful enough for manned spaceships is still a concept and pipe dream now (Yes AdAstra I'm looking at YOU), with acceleration unsuitable for humans, solar panels offer rather small energy density and for larger engines you would need array with power output exceeding ISS solar arrays size (and weight) by many folds...

Ion probes are a bad example, because those are small crafts with negligible acceleration (good if you had years to spare), so this is not technology usable for space travel for many decades to come.

Unlike electric propulsion there was tested prototypes of NTR rockets that could be adapted for actual flight, so it's much more realistic technology than electric propulsion.

Also I think that for first manned missions to mars chemical propulsion can made the job as well, we don't need any special rocket to make it done.

Edited by karolus10
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It is not proven fact that you need artificial gravity for long stays in space. Temporary bone loss can be mitigated with diet and exercise (some people may even have a genetic advantage in this, because the effects vary from astronaut to astronaut).

[citation needed]

Here's your citation.

And while you don't strictly need artificial gravity, it could be helpful, especially as this "bone-less medication" you mention would likely cost an awful lot of money, as does bringing any drug to market. Exercise and diet does help to an extent, but after longer-term missions it wouldn't be nice coming back to solid ground again...

There is actually a plan to put a small ring shaped centrifuge on the ISS and possibly use it as sleeping quarters, but it hasn't been confirmed yet, (it was part of the Nautilus X plan if anyone wants to have a look).

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It doesn't matter. NERVAs are not going to happen because nobody with power and/or money wants it to happen. Meanwhile, chemical and solar electric propulsion is working great and is being used already. I don't understand the obsession with NTR or other pipe dreams when we have current hardware that can be built and used with proper long term planning. You also don't need nuclear reactors to power solar electric propulsion and you can most definitely go to Mars or further away. Have you not heard of Deep Space 1, Dawn or Hayabusa?

Well, if you are thinking of the political problems with launching nuclear material into space, you´re out of luck, both Voyager, pioneer are prime examples of probes using RTG´s (tiny heatbased nuclear reactors) for power. You could argue that those where launched years ago, but then Curiosity, wich drive around on Mars right now, also use a RTG as a heat and powersource. So, nuclear material is being launched and used "today".

A NTR (Nuclear Thermal Rocket) could conceviably be designed as multiple RTG´s launched separately (for added safety) and working as a combined heatsource, be used to heat the fuel as it is used, and that way, give a significantly higher ISP compared to a purely chemical rocket.

Doing that would make the weight needed to be launched into earth orbit significanlty less than if it was based on chemical alone. And, if the return trip will be with a smaller part of the initial vessel, then some of the RTG´s could be used as a second source of heat and power if the point is to estabelish some kind of base/colony.

The technical reality of the situation right now is that while electric propulsion is both proven, quite evolved and very efficient, the thrust is still so small that it would only be practical for unmanned cargo and supplies launched years in advance. Due to medical and logistical reasons, you don´t want to have a crew in 0 G for a decade before they arrive in Mars orbit. As a practical alternative, mostly only NTR and chemical is your only option for the human part of the cargo. If you can halve the amount of fuel, and shorten the trip to some 6 months, using nuclear propulsion for getting to mars, odds are, there will be not an insignificant amount of political support for such an option.

Nobody wants nuclear propulsion to be a thing, stop trying to make it a thing. Effort needs to go toward convincing the powers that be that human exploration of space (beyond what's already been accomplished) is an important priority.

Ok, this argument is just plain silly. "Because lots of people don´t like this, don´t discuss it as a viable sollution, because someone just might want to look into it"? Please please please please pretty please explain WHY you said something like that.

It is not proven fact that you need artificial gravity for long stays in space. Temporary bone loss can be mitigated with diet and exercise (some people may even have a genetic advantage in this, because the effects vary from astronaut to astronaut).

There is something called "google" on the interweb, I´ll give you a hint: Nasa have performed a lot, and I mean a LOT of science into this, even the russians have done their share of research into this. While there are quite a lot an astronaout can do, and behelped with to counteract the negative effects of long term microgravity, concensus is that gravity would solve a lot of problems. A much shorter trip would also help a lot.

I don't think you two understand that this would be another budget line item. NASA operates with finite resources; finite numbers of people and money to use on projects like these. Real world space programs are not Kerbal Space Program. Do you have any idea how many billions of dollars this would cost? Then, many years and billions of dollars later when the experiments are done, even if it's entirely positive and is shown to work, untold billions and years have to be spent working them into spacecraft operations and hardware. All that for artificial gravity, when a treadmill has been shown to work just fine. All that for nuclear propulsion, when we've used chemical propulsion since the dawn of manned flight and solar electric proulsion for two decades.

The linked sollutions/experiments wouldn´t cost multiple billions of dollars. What kind of sollutions they would lead to is ofcourse not easy to say now, but a threadmill is NOT a perfectly good sollution in the long run, or for long missions either. Even with extended use of training and dieting and medication, there is significant deterioration of an astronauts bone, muscles and internal organs. Again, a shortening of the trip itself, or artificial gravity would coutneract this much more efficient than "a threadmill". If only it was that simple.

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Main problem is that Solar electric propulsion powerful enough for manned spaceships is still a concept and pipe dream now (Yes AdAstra I'm looking at YOU), with acceleration unsuitable for humans, solar panels offer rather small energy density and for larger engines you would need array with power output exceeding ISS solar arrays size (and weight) by many folds...

Ion probes are a bad example, because those are small crafts with negligible acceleration (good if you had years to spare), so this is not technology usable for space travel for many decades to come.

Unlike electric propulsion there was tested prototypes of NTR rockets that could be adapted for actual flight, so it's much more realistic technology than electric propulsion.

Also I think that for first manned missions to mars chemical propulsion can made the job as well, we don't need any special rocket to make it done.

Did you not read my last post? It seems that you are woefully ignorant of the subject we are discussing. There have been many spacecraft since over a decade back that have used solar electric propulsion successfully. They include:

- Deep Space 1

- Hayabusa

- SMART-1

- Dawn

Dawn just finished thrusting continually for 31.2 days, beating the previous record of 29.2 days set by Deep Space 1. While solar electric propulsion is not cheap, it works tremendously well. For instance, to get into orbit around Mars, a chemically propelled spacecraft of that size would need 300 kg of propellent where as Dawn would only have to use about 1/10th as much, 30 kg worth of xenon, to accomplish the same change in velocity. While it would take 25 minutes for the chemical rocket to do this it would take Dawn up to 3 months but you also have to factor in the much reduced travel time to get to Mars. [source] Chemical propellents will get you up to speed quickly but only for a limited time, and then you'll spend most of the time coasting to Mars. With solar electric propulsion you would accelerate (slowly) to high speeds then decelerate, and you'd be firing the engines for the majority of the trip. It would still be cheaper in terms of kgs because with solar electric propulsion you need less fuel to get a faster speed compared to a run of the mill chemical rocket engine. Dawn can perform a total velocity change of more than 10 km/s using 425 kg of propellent [source]

As for the solar panels: Dawn has two 2.3 x 8.3 meter solar arrays that provide 10.3 kW at 1 AU and while I couldn't find the exact weight it shouldn't be more than 200 kg for the entire electrical system, panels included. You would not need ISS sized solar panels to power an upscaled ion thruster as you could make more use of batteries or an alternative power source (RTG for example). You could also use hybrid systems where you use a chemical tug to provide the initial Mars burn and then rely on solar electric propulsion to accelerate even further, then decelerate. You couldn't land on Mars using solar electric propulsion so the lander would have to have chemical propulsion anyway. Or, as you write, you could use chemical propellents although this means a heck of a lot more in terms of cost - in money and in kg you have to bring up. You can get about 20-25% of your mass in GTO to Mars so if you want to get an 8 tonne (just an example) lander and spacecraft to Mars you'd have to put an Earth departure stage weighing 40 tonnes into GTO. We don't have such a rocket today because of lackluster funding and direction, not because we don't have NTR propulsion up and running.

When you post something like "Unlike electric propulsion there was tested prototypes of NTR rockets" I can't help but think what on Earth you've been reading. NTR was last tested four decades ago and has never flown where as solar electric propulsion is flying and being used today, this very second as I type this, on an active mission. You would have to understand that to get NTR to the same level of technology would take years and billions of dollars and first of all it has to get signed off on by lawmakers. I don't know how to make it any clearer:

It's not going to happen and it doesn't need to happen to get humans to Mars or beyond; in fact it would only slow progress in that direction down. I have no doubt that you are passionate about human space exploration but you are making all the wrong sorts of bets. You need to stop drinking Robert Zubrin's kool aid and get real.

Here's your citation.

And while you don't strictly need artificial gravity, it could be helpful, especially as this "bone-less medication" you mention would likely cost an awful lot of money, as does bringing any drug to market. Exercise and diet does help to an extent, but after longer-term missions it wouldn't be nice coming back to solid ground again...

There is actually a plan to put a small ring shaped centrifuge on the ISS and possibly use it as sleeping quarters, but it hasn't been confirmed yet, (it was part of the Nautilus X plan if anyone wants to have a look).

While that is a dubious source you've linked to - site owner links to his own research and there's a page on that site that lists 19 different effects of microgravity including "flatulence" [insert mental image of me striking my face with my palm] - it doesn't prove your point. Au contraire, the guy appears to be looking at long-term, near permanent stay scenarios which is not all what I am concerned and it is not in any way shape or form going to be the norm in the years to come. We haven't even set foot in deep space since the 70s so that stuff is all a long ways away. Several humans have been in microgravity for a year or more at a time, some for a total of a year and a half, and they're perfectly healthy.

You too seem woefully ignorant of some very basic elements of human space exploration. Bone loss is not a new thing, it occurs here on earth too. It's called osteoporosis and it affects 55% of Americans aged 50 and above. The magic "bone-less medication" I mention would not cost an awful lot of money. It's Vitamin D and calcium, and putting that into astronaut's diets is something NASA does already. On the ISS you are required to exercise for 2 hours every day and it seems to work just fine, as the hundreds of collective years of humans staying on the ISS can attest to. For example, it took Chris Hadfield about a week to get his body acclimatised to space (this also varies) and then once he returned to Earth his body returned to normality pretty quickly. Humans are adaptable.

Oh and there are no plans to put a centrifuge on the ISS but while you mentioned it it is worth pointing out that being subjected to a centrifuge every now and then while in space could also minimise the effects of micro- or no gravity environments on the body. You can read more about it here. Again, this sort of stuff adds weight and every kg you add is an increase in launch costs. How many times do I have to remind you people that there's already very little political will or money for human spaceflight.

As for your post Thaniel I feel like I already covered a lot of your points in my replies to karolus10 and GJames. The three of you seem to live in this la la land where practicality, money and doability is not even remotely an issue and where there are seemingly no downsides to any of your proposals. You are welcome to present evidence to support your crazy, inane position that NTR and artificial gravity are more feasible, technologically ready, politically safe and less costly than solar electric propulsion and exercise + diet.

I am not going to hold my breath.

Edited by Borklund
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Did you not read my last post? It seems that you are woefully ignorant of the subject we are discussing. There have been many spacecraft since over a decade... etc. etc. [snip]

As you have branded Thaniel's, karolus10's and my views as inane and crazy, I doubt that we could do anything to convince you otherwise, (although they can if they want to). The fact that you didn't directly answer Thaniel's post when, in my own but obviously inane and crazy opinion, systematically refuted nearly all of your points, seems to suggest that you couldn't come up with any decent answers.

Your posts all seem to have the tone that your opinions are more important than everyone else's and you do indeed intersperse your points with various insults, as if to prove how ignorant we are. Not generally a good to e to take when this is supposed to be a discussion, not an argument.

As for living in la-la land, I would far rather be optimistic and hopeful for new technologies than poo-poo any that don't fit into your view of how spaceflight should be.

EDIT: If you had paid any attention to the source that I linked you to, you would've seen that the research presented on the page was in turn linked to the Graybiel Lab at MIT, who originally conducted the research. That's a bit less dubious right?

Edited by GJames
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Okay, let's take a step back.

First of all, I'm sorry if my post came off as hostile. While I don't agree with you I did not mean to be disagreeable in doing so. That said, I can't think of a better adjective than inane when I see statements like "NTR is more ready than solar electric propulsion" when this is factually just not true.

My larger point is that it has not been proven that you need NTR or artificial gravity to explore deep space so why put precious few resources into getting those things flying - because they haven't yet, not even in subscale demonstrators. It doesn't have anything to do with my view of how spaceflight should be; it's all about practicality. NTR and artificial gravity might be fantastic ideas, as are giant spaceships and other sci-fi concepts, but we are in the real world where there are real factors to consider, factors that you choose to simply ignore, such as technological readiness, political considerations and cost.

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Well, If You want to save money - send more rovers then, manned spaceflight is an expensive investment and this can't be avoided.

Did you not read my last post? It seems that you are woefully ignorant of the subject we are discussing. There have been many spacecraft since over a decade back that have used solar electric propulsion successfully.

My dear, I understand Your point perfectly and I think that your "bets" on electric propulsion are flawed.

Electric propulsion has a bright future, but for small probes, attitude control or station keeping/space tugs ,but would not serve as main propulsion for larger spacecrafts in next few decades (and most likely not in our lifetime).

You are citing Ion probes as an example of feasibility of electric propulsion, but most of them are very small and weight less than a 500Kg (with exception of dawn probe that weight 1.2T) and it's propulsion wouldn't be able to break the orbit on their own and reach mars in reasonable time (even tiny spacecraft without payload).

Small and cramped Soyuz spacecraft weight 5 metric tones, and mars missions payload would weight at least 40-60 T. Upscaling propulsion to being feasible for larger spacecraft (80+ times larger spacecraft) aren't easy feat and we won't get powerful enough engines in next 30 years (or more).

It's not going to happen and it doesn't need to happen to get humans to Mars or beyond; in fact it would only slow progress in that direction down. I have no doubt that you are passionate about human space exploration but you are making all the wrong sorts of bets. You need to stop drinking Robert Zubrin's kool aid and get real.

Personally I think that Dr. Zubrin is right in many topics.

The three of you seem to live in this la la land where practicality, money and doability is not even remotely an issue and where there are seemingly no downsides to any of your proposals. You are welcome to present evidence to support your crazy, inane position that NTR and artificial gravity are more feasible, technologically ready, politically safe and less costly than solar electric propulsion and exercise + diet.

You think that NTR engines are waste of time, because we can use this resources to get electric propulsion working (≠ tiny probes use), but it won't happen quickly.

First generation of working NTR engines could be used in 10-15 years (or less), this technology can be adapted faster and cheaper (both flight and R&D cost) than electric propulsion and it would be most likely only alternative to chemical rockets in this half of century.

I suggest You rethink what is more doable and realistic to do, I'm happy to hear more arguments proving this case :).

Edited by karolus10
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Both Nuclear Thermal Rockets (NTR) and Solar Electric Propulsion (SEP) have been discussed for use on a manned Mars mission. SEP has already been proven in space, although not at the scale needed for a manned Mars mission. NTR has been demonstrated on the ground (not for a long time though) and is at a TRL of 6. An NTR or SEP stage capable of human missions to Mars could be developed within 10 years, which is in time for the first planned Mars mission in 2033. Low-power SEP (of the kind we pretty much already have) has mostly been suggested for cargo missions, since it has a much longer transit time. High-power SEP (on the order of 1 MW) or NTR could also be used for crew transport. Chemical propulsion works too, but much more mass to LEO is needed, which drives up costs. Basically, we have to weigh the development costs for SEP/NTR versus the high per-mission costs of chemical propulsion (some development is also needed for this scale of chemical propulsion, such as cryogenic storage).

Also, the reason why NTR has not been worked on in so long and has a low chance of actually being used, even though it's a good option, is because it has the word "nuclear" in it. The public is still deathly afraid of "nuclear" things and it will take some effort for NASA to convince people that it's safe.

There was a conference on this recently, they went through almost every issue you can think of with a manned Mars mission. You can see some of the videos here, ... although it looks like the server is not working right now.

Here's a chart comparing propulsion options (cryo means chemical):

qRMrmQN.png

When you think about even the big SLS rocket being developed by NASA having a max planned payload of 130 tons to LEO, the amount of launches you need to get all that cargo to LEO for a single Mars mission using only chemical rockets becomes ridiculous (and this is only for getting to Mars orbit and back, not even landing).

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Also, the reason why NTR has not been worked on in so long and has a low chance of actually being used, even though it's a good option, is because it has the word "nuclear" in it. The public is still deathly afraid of "nuclear" things and it will take some effort for NASA to convince people that it's safe.

I think there is one of main reasons, recently there has been announced plans of building first nuclear power plant in Poland (less than 20 kilometers from place I live now). There where many people protesting (I see still many anti-nuclear posters in city) against building it and many people I know think that this is a death-trap, not mention about thousands of people possibly loosing jobs from touristic segment.

If people are scared, any reasoning can't help.

075.jpg

Edited by karolus10
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  • 1 month later...
To be honest, taking big tanks of water is a GOOD idea (one I knew of already). They could use the water at the end of the journey. But there is one problem... coming back. No way of launching water to orbit at Mars so it would be one way or they would have problems with cancer, eyesight (yeah, shocked me too) and even would affect their cognitive functions. Cosmic radiation is a bitch, let alone solar radiation that they would be running into on the way back.

I think that until we either get faster craft or we get better cancer drugs and/or shielding tech we won't be going to Mars.

In the meantime, I wonder if someone will write a Radiation Exposure mod for KSP. Would be an eye opener I think.

This isn't the most glamorous idea, but the hydrocarbons found in human waste can apparently stop radiation. I found this fact out while watching an episode of The Universe on the History channel. The idea would be to place waste between the exterior and interior walls in a hermetically sealed tank (for obvious reasons.) Maybe a bag approach similar to self sealing fuel tanks would work. While a water bladder was drain for crew use, a waste bladder would be inflated. The water bladder would be above the waste bladder to prevent any leaks from contaminating the water supply. The same properties apply for food, since most food items (with the exception of salt) contain hydrocarbons. Basically, they use their food and (I'll leave this to your imagination) to shield themselves from radiation. The short flight up to a return ship will expose them to relatively low doses of radiation. Then just use the same principle with the lander to shield the hab modules on the return trip to Earth.

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According to the OP's article, isn't the radiation of deep space more of a concern than the radiation on the surface of Mars? I didn't read all of the pages of this thread, so maybe this was already discussed.

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According to the OP's article, isn't the radiation of deep space more of a concern than the radiation on the surface of Mars? I didn't read all of the pages of this thread, so maybe this was already discussed.

Correct. While Mars has a tenuous atmosphere it does seem to provide adequate protection from galactic cosmic rays (GCR) and other sources of radiation that astronauts would be very exposed to on the long journeys to and from Mars. The consensus seems to be that radiation is an issue, but not a showstopper, given good enough shielding and mitigation strategies.

Nasa's guidelines say that astronauts should not be exposed to more than 1,000 millisieverts (mSv) of radiation in a lifetime, which is associated with a 5% increase in risk of developing a fatal cancer. According to the latest study, based on data from MSL's Radiation Assessment Detector (RAD), astronauts on a 360-day round trip to Mars would get a dose of 662mSv on their journey.

"In terms of accumulated dose, it's like getting a whole-body CT scan once every five or six days," said Cary Zeitlin, a principal scientist in the Space Science and Engineering Division of the Southwest Research Institute in Boulder, Colorado, who led the study. His results are published on Thursday in the journal Science.

http://www.sciencemag.org/content/340/6136/1080

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According to the OP's article, isn't the radiation of deep space more of a concern than the radiation on the surface of Mars? I didn't read all of the pages of this thread, so maybe this was already discussed.

Even if there were no atmosphere, the radiation on Mars would be at most half of what it is in deep space. This is because you have the bulk of the planet itself blocking half the sky. (This works on any planetary surface.) And the atmosphere of Mars does provide a little extra protection. So the radiation dose while on the surface of Mars might be about 1/4 to 1/3 that of deep space.

edit: It seems the radiation dose on the surface of Mars is similar to the radiation in LEO, which is about 200 mSv per year. And the radiation in transit to Mars would be 660 mSv per year.

Edited by metaphor
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We need to find water on mars itself. Just like we drill for oil here wed do the same on Mars, but with water. Once you drill and find water you build the hab module over it. As for the radiation. Well...fill the walls with feces. Lmao as nasty as that sounds its very practical.

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Developing effective lightweight shielding is a materials challenge, but there's no reason to think it's an insurmountable one.

However, it's things like this that do show just how impractical it is to send humans on long-duration spaceflights. I'm not at all optimistic about the prospects for manned flight beyond Earth orbit. Machines are just so much better suited to the challenges of space and the extreme environments on other planets than we are.

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I've personally singed up for Mars One and would love to travel to Mars... Even if it is a one way trip.

The way I see it, Mars One is either a scam or a mission that is too optimistic and not worth the cost (currency and human lives). If you want to send people to mars, get a legitimate space company not pulling random people off the street to go to mars.

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The way I see it, Mars One is either a scam or a mission that is too optimistic and not worth the cost (currency and human lives). If you want to send people to mars, get a legitimate space company not pulling random people off the street to go to mars.

Selling advertising is in no way a realistic way of funding a permanent colony on Mars. Who pays for the supply flights once the buzz has died down and they can't sell the advertising? I'm concerned that they're so eager to condemn some very brave altruistic people to a nasty death. Personally I rate the chances of them actually getting any boots on the red planet as very low.

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