Author Topic: James Logan, MD. living on Mars. Opinions on his conclusions.  (Read 40523 times)

Offline Paul451

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For instance, at 2:00 she measures 10uSv/h. Mean natural background on Earth is below 0.3uSv/h.

So 0.24mSv/day? Or about a third as much as the surface of Mars. About a quarter of one percent of the levels in open space.

perhaps you could address my points if you still think he wasn't advancing Deimos as "the perfect place" for off Earth Human settlement.

Sure, the moment you show where I said anything remotely like that.

Offline Alf Fass

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But then his "do it first" architecture requires building spinning ONeill colonies inside Deimos!
So Mars surface living is too hard and too many unknowns to go there, but a giant rotating underground Deimos base is doable?

Don't be silly. That was clearly meant to show the long term potential for permanent colonisation. It was meant to end the "downer" lecture on an upnote. "You don't have to give up the dream of space colonisation..." It wasn't meant to be his actual proposed Deimos mission.

While Paul451 didn't think his Deimos idea was intended to be taken too seriously: http://forum.nasaspaceflight.com/index.php?topic=40485.msg1546944#msg1546944
(Dr. Logan talks about it from the 48 minute mark) he sure seems to be presenting it as his preferred asteroidal colony location to me.

His Deimos idea is to have a small hab under 7m of Deimosian regolith, teleoperating science equipment on the surface of Mars, with ISRU water for return propellant (and air/water, obviously).

The depiction of Island One is meant to show the scale of resources available. He's not seriously proposing a chain of Bernal spheres tunnelled through Deimos. And he's certainly not proposing it as an alternative to a small manned base on Mars. It's just "This is a Bernal sphere next to the Empire State Building. Big isn't it? Now this is a small tunnel through Deimos, each of these small dots in the small tunnel is a full sized Bernal sphere, each can hold ten thousand people. GET IT?! That's your inspiration, your space-cadet vision. Being 'limited' to moons/asteroids is no limitation whatsoever."

The form of a true colony on (or rather in) Deimos would be wildly different than an open-space structure like Island One.

Certainly seems to me that you're dismissing him having seriously advanced open-space structures like Island One inside Deimos as the most likely form of initial space colonization.

If that's not what you're saying, say what you actually mean instead of playing clever self congratulatory word games.
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Offline QuantumG

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Mirrors are pretty well matured technology.
Human spaceflight is basically just LARPing now.

Offline gospacex

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For instance, at 2:00 she measures 10uSv/h. Mean natural background on Earth is below 0.3uSv/h.

So 0.24mSv/day? Or about a third as much as the surface of Mars. About a quarter of one percent of the levels in open space.

I was simply replying to someone who mistakenly believes that in Chernobyl, "the levels of radiation dropped back to background a /long/ time ago". Whereas the truth is that levels will not return close to natural background level for at least a century.

I see a lot of downplaying of the scale of Chernobyl from Western techies, and much ignorance. Even at physicsforums.com, "Nuclear Engineering" subforum, where you'd think people would know what they are talking about, I see claims that "only 28 people died in Chernobyl", "there are no thousands of square kilometers evacuated around it" etc.

Offline gospacex

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Reflect a bit why there is a Moon/Mars debate - because Mars, while located much farther from Earth, has numerous advantages over the Moon and other airless bodies like Deimos.

Mars has abundant and trivially accessible source of CO2. You can make oxygen from it. You can make carbon from it. You can make CO from it (and thus, fuel/oxidizer pair for rockets and power generation).

It's possible extracting water vapor from Mars atmosphere will be economical too. If not, Mars has permafrost on much of its surface, and maybe even everywhere.

Mars dust is much less mechanically aggressive than Moon dust - it's weathered.
« Last Edit: 06/10/2016 12:39 pm by gospacex »

Offline Oli

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Real estate for the super-rich is the only potential reason I see for building a space colony. Hence it's going to be a rotating station in equatorial LEO with a nice view on the blue planet and low-g recreational facilities. Nobody wants to live inside Deimos.

It would have been much better to criticise DRM 5 or the Evolvable Mars Campaign. It is not the space cadets that are suggesting 1100 days in space (transit and Phobos) for the first mission, it is NASA.

1100 days in space is probably ok if you raise the career radiation limit somewhat.
« Last Edit: 06/10/2016 04:05 pm by Oli »

Offline MikeAtkinson

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Real estate for the super-rich is the only potential reason I see for building a space colony. Hence it's going to be a rotating station in equatorial LEO with a nice view on the blue planet and low-g recreational facilities. Nobody wants to live inside Deimos.

It would have been much better to criticise DRM 5 or the Evolvable Mars Campaign. It is not the space cadets that are suggesting 1100 days in space (transit and Phobos) for the first mission, it is NASA.

1100 days in space is probably ok if you raise the career radiation limit somewhat.
And send older all-male crews which have not had extensive spaceflights before.

Offline philw1776

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Medical tests while on Mars will be important on these early missions. It would settle the question if .38g is enough gravity. If the crew still suffers from bone loss and other issues, that would complicate any colonization plans to say the least.

Randomly selected candidates for in-situ vivisection should answer the questions.
FULL SEND!!!!

Offline Robotbeat

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Medical tests while on Mars will be important on these early missions. It would settle the question if .38g is enough gravity. If the crew still suffers from bone loss and other issues, that would complicate any colonization plans to say the least.

Randomly selected candidates for in-situ vivisection should answer the questions.
I will not be voting for you for the medical ethics board. ;)
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Offline john smith 19

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Borrowed from Doesitfloat's post here:
http://forum.nasaspaceflight.com/index.php?topic=40464.msg1546539#new

Dr. Logan expresses opinions on several matters, and at the end of the video concludes that the best place for future space settlement isn't on Mars, or the Moon but rather in O'Neill colonies within Deimos, which surprised me as I would have thought smaller asteroids nearer to Earth, perhaps with some shifted into orbits about the Earth - Moon system, would have had huge advantages, especially as the high radiation exposure of longer interplanetary transit times was a major part of his presentation.

Opinions?
AFAIK Perchlorates are used as industrial cleaning agents  and in processing fabrics on Earth.

This does not sound like something you want to be trailing around your home.

Likewise the other fines sound like you want to keep them out as well, Noting Dr Logan's suggestion to look for solutions I'm wondering if some kind of electrostatic system could strip them off an EVA suit well enough.

Once on the surface things look quite doable for radiation protection inside habs, while remote avatars should be able to supply operators with a very immersive experience. However the surface radiation level will have serious implications for plant growth.  That's not say you couldn't do it using mirrors to avoid direct LOS from any radiation source.

But that still leaves gravity, and that's pervasive. An interesting question (which still has had a very limited response to being answered) is can you use "bursts" of gravity, using a short radius centrifuge to  counteract micro g effects.  Such a system would pay big  dividends in ship design as full rotation of the living quarters would no longer be mandatory for good long term health.

For some of these cutting transit time will help but it will not stop degeneration. It' s also important to note some of this degeneration looks permanent.

IOW the only way to "fix" it is to not get it in the first place.  :(

The alternative would be a drug development programme to combat these effects. I'm not sure if anyone knows where to begin with such requirements.  :(



MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline Rocket Science

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Reflect a bit why there is a Moon/Mars debate - because Mars, while located much farther from Earth, has numerous advantages over the Moon and other airless bodies like Deimos.

Mars has abundant and trivially accessible source of CO2. You can make oxygen from it. You can make carbon from it. You can make CO from it (and thus, fuel/oxidizer pair for rockets and power generation).

It's possible extracting water vapor from Mars atmosphere will be economical too. If not, Mars has permafrost on much of its surface, and maybe even everywhere.

Mars dust is much less mechanically aggressive than Moon dust - it's weathered.
Mars dust presents the equally challenging problem of being so fine that it is difficult  to keep out of mechanisms  such as suit bearings...
"The laws of physics are unforgiving"
~Rob: Physics instructor, Aviator

Offline Dalhousie

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Reflect a bit why there is a Moon/Mars debate - because Mars, while located much farther from Earth, has numerous advantages over the Moon and other airless bodies like Deimos.

Mars has abundant and trivially accessible source of CO2. You can make oxygen from it. You can make carbon from it. You can make CO from it (and thus, fuel/oxidizer pair for rockets and power generation).

It's possible extracting water vapor from Mars atmosphere will be economical too. If not, Mars has permafrost on much of its surface, and maybe even everywhere.

Mars dust is much less mechanically aggressive than Moon dust - it's weathered.
Mars dust presents the equally challenging problem of being so fine that it is difficult  to keep out of mechanisms  such as suit bearings...

We routinely operate equipment in environments full of fine dust on Earth.  But when we get to Mars it apparently becomes an insurmountable problem.
Apologies in advance for any lack of civility - it's unintended

Offline john smith 19

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Reflect a bit why there is a Moon/Mars debate - because Mars, while located much farther from Earth, has numerous advantages over the Moon and other airless bodies like Deimos.

Mars has abundant and trivially accessible source of CO2. You can make oxygen from it. You can make carbon from it. You can make CO from it (and thus, fuel/oxidizer pair for rockets and power generation).

It's possible extracting water vapor from Mars atmosphere will be economical too. If not, Mars has permafrost on much of its surface, and maybe even everywhere.

Mars dust is much less mechanically aggressive than Moon dust - it's weathered.
Mars dust presents the equally challenging problem of being so fine that it is difficult  to keep out of mechanisms  such as suit bearings...

We routinely operate equipment in environments full of fine dust on Earth.  But when we get to Mars it apparently becomes an insurmountable problem.
That depends if you're comparing like with like.

What fraction of Earth dust is easy to inhale deep into the lungs, like Asbestos for example?

What fraction of that dust is not basically discarded skin and hair cells but actual abrasive rock particles?

What fraction of that dust is aggressively chemically active, like drain cleaner or industrial bleach?

I'm pretty sure all Earth dust grains (at the microscopic level) are smoother, larger and less chemically reactive. Most chemically reactive dust will have reacted with water vapour (or actual water) Millenia ago. I also think the processes that result in grain splitting are either different or terminate with a larger average grain size than Moon or Mars processes.
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline Paul451

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Mining is about the only directly comparable activity. Freshly ground rock is the closest thing to raw regolith. And part of my own skepticism about surface activity on the moon and Mars comes from the response I got from people with mining experience when discussing my own naive space-cadet visions back in the '80s. People with experience in mining do not handwave away dust/etc and call it a solved problem, they immediately start pointing on the problems with dust and maintenance, with dust and health, with EVA-suits and mobility/safety, etc. "Dust gets into everything" is the most repeated phrase I heard.

Offline gospacex

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However the surface radiation level will have serious implications for plant growth.  That's not say you couldn't do it using mirrors to avoid direct LOS from any radiation source.

Wrong.
Plants are generally more resistant to radiation than humans. (A notable exception is pine, which is similar to humans).
Even in Chernobyl, pines show radiation effects only in a rather small severely contaminated area with radiation levels at least 1000 times above Earth average.

In any case, there is no reason to worry if plants would have, say, even 10% higher mutation rate than on Earth - we are going to grow them for _food_, not aestetics.

Offline john smith 19

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Mining is about the only directly comparable activity. Freshly ground rock is the closest thing to raw regolith. And part of my own skepticism about surface activity on the moon and Mars comes from the response I got from people with mining experience when discussing my own naive space-cadet visions back in the '80s. People with experience in mining do not handwave away dust/etc and call it a solved problem, they immediately start pointing on the problems with dust and maintenance, with dust and health, with EVA-suits and mobility/safety, etc. "Dust gets into everything" is the most repeated phrase I heard.
Indeed Silicosis, Asbestosis and Berylosis are all basically "fine dust from X gets into lungs" conditions.

This suggests you're looking at much more than a simple air lock design. If you could make the suit surface electrostatically repel the dust then suck it away that would the most effective approach but some kind of air blast over all surfaces would seem to be needed.

If it's their chemical reactivity that's an issue then perhaps adding some warm Methane into the airlock area would burn it off? A water mist system should also work but you've got multi phase flow to deal with then. The inert parts of the dust would still remain and be abrasive however.

Note that with the recognition of a greatly increased radiation exposure, and a capsule offering maybe 5% of the protection of the Earth's atmosphere Regolith handling becomes an essential early need to allow "digging in." I wonder if SX are planning on a small semi-autonomous excavator for one of those Dragon capsules?

I had not realized till Logan's talk just how little time has been spent on the Moon by any single person. Even all put together (600 hrs?) it's as much as the shortest feasible stay on Mars.

People talk about the transit time but IIRC the shortest stay time is about 3 months. I don't think space weather forcasting is good enough to reliably a safe window for this. You will have to land and dig in ASAP, even if it's basically laying sand bags around (and on top) of the shelter.

Space cadets might want a nice new shiny spaceship but the more I see of the problems the more I like the idea of capturing a NEO, coring it out and picking up a 2m rock layer all around in LEO essentially for free.

And that still leaves gravity.  :(
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline Rocket Science

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Reflect a bit why there is a Moon/Mars debate - because Mars, while located much farther from Earth, has numerous advantages over the Moon and other airless bodies like Deimos.

Mars has abundant and trivially accessible source of CO2. You can make oxygen from it. You can make carbon from it. You can make CO from it (and thus, fuel/oxidizer pair for rockets and power generation).

It's possible extracting water vapor from Mars atmosphere will be economical too. If not, Mars has permafrost on much of its surface, and maybe even everywhere.

Mars dust is much less mechanically aggressive than Moon dust - it's weathered.
Mars dust presents the equally challenging problem of being so fine that it is difficult  to keep out of mechanisms  such as suit bearings...

We routinely operate equipment in environments full of fine dust on Earth.  But when we get to Mars it apparently becomes an insurmountable problem.
I never said "insurmountable"... I said it was "challenging"... Covering your ears and eyes with your hands won't solve the engineering required, only meeting the challenge will...
"The laws of physics are unforgiving"
~Rob: Physics instructor, Aviator

Offline Paul451

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but the more I see of the problems the more I like the idea of capturing a NEO, coring it out and picking up a 2m rock layer

Unfortunately, all these problems apply to asteroid mining too.

Plus microgravity.

Once on the surface things look quite doable for radiation protection inside habs, while remote avatars should be able to supply operators with a very immersive experience. However the surface radiation level will have serious implications for plant growth.  That's not say you couldn't do it using mirrors to avoid direct LOS from any radiation source.

As discussed (argued about) at length in the "Scaling Ag on Mars" thread, mirrors are a bad solution on Mars for grow modules. Concentrating reflectors only work for direct light. The dust in Mars' atmosphere means that a surprising amount of sunlight is scattered, even when the total amount of light reaching the surface is barely altered. A "clear day" might have a 30% reduction in direct sunlight, a typical summer day might lose up to 60% of direct light, a light dust storm will drop that to 10%; all without reducing the total amount of light reaching the surface.

(That probably isn't an issue for bringing some natural light into habitat areas, because your eyes adapt to widely varying light levels. But crop growth-rates are highly dependent on W/m˛.)

Offline Robotbeat

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People have this idea that there's going to be a whole lot of people going into and out of airlocks all the time.

No. If there are large settlements on Mars, they will be like downtown Minneapolis (all the buildings connected with air conditioned skyways or tunnels) or like indoor shopping malls (which were invented in Minnesota due to the harsh winters) or college campuses in Minnesota (connected via tunnels). Huge indoor spaces. You don't go outside. You might get in vehicles, but you do so via tunnels or garages. And on Mars, there will be few places worth going that are outside other than ones that you'd travel to via trains or something similar.

You'll have few people going outside. It'll be like construction workers or miners (people who even on Earth have to deal with similar hazards as dust). Not ANYWHERE near the majority of the population.

So yeah, I think the dust issue is overblown for settlements, because settlements won't be a series of unconnected buildings like most places on Earth. They will be buildings connected via tunnels or large integrated buildings (like the Amundsen–Scott South Pole Station). And eventually, they will be buildings inside large domes or other megastructures. You're simply not going to be tracking fine, unmodified dust everywhere because you simply won't be going outside much.
« Last Edit: 06/12/2016 05:56 pm by Robotbeat »
Chris  Whoever loves correction loves knowledge, but he who hates reproof is stupid.

To the maximum extent practicable, the Federal Government shall plan missions to accommodate the space transportation services capabilities of United States commercial providers. US law http://goo.gl/YZYNt0

Offline gospacex

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Mining is about the only directly comparable activity. Freshly ground rock is the closest thing to raw regolith. And part of my own skepticism about surface activity on the moon and Mars comes from the response I got from people with mining experience when discussing my own naive space-cadet visions back in the '80s. People with experience in mining do not handwave away dust/etc and call it a solved problem, they immediately start pointing on the problems with dust and maintenance, with dust and health, with EVA-suits and mobility/safety, etc. "Dust gets into everything" is the most repeated phrase I heard.
Indeed Silicosis, Asbestosis and Berylosis are all basically "fine dust from X gets into lungs" conditions.

This suggests you're looking at much more than a simple air lock design. If you could make the suit surface electrostatically repel the dust then suck it away that would the most effective approach but some kind of air blast over all surfaces would seem to be needed.

If it's their chemical reactivity that's an issue then perhaps adding some warm Methane into the airlock area would burn it off? A water mist system should also work but you've got multi phase flow to deal with then. The inert parts of the dust would still remain and be abrasive however.

What makes you think Mars dust is abrasive? Did MER wheels fall off? Did their camera masts seize?

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