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Colonizing the Outer Solar System
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Graeme
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Jul 24, 2018 11:12PM
With the magneto-plasma engines, what are likely opportunities to pick up propulsion fuel within the solar system, looks like they would be using Argon or Xenon?
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Actually, the atmosphere of Mars is composed mostly of CO2, but also of 2% of Argon. That Argon could be extracted from the Martian atmosphere and liquefied before being sent to an orbital refuelling station. With a specific impulse of up to 9,000 seconds, magneto-plasma engines, like the VASIMR, are ten times more efficient than nuclear rocket engines like the American PHOEBUS 2 (developped in the 1970s but then dropped by NASA for budgetary reasons), which are themselves over twice as efficient as our best chemical rocket engines (liquid oxygen and hydrogen, S.I. of 420-440 seconds). I envision a ship that would use the high thrust of nuclear rocket engines to depart Earth orbit and accelerate towards Mars, to then have the VASIMR engines take the relay for a very gentle but also very long boost to shorten the trip significantly (Earth-Mars in 1-2 months with PHOEBUS 2 + VASIMR instead of the actual nine months with chemical rockets). Such magneto-plasma engines would be ideal on the long trips to Jupiter and Saturn, until we could finally develop thermonuclear fusion rockets. Once we will have fusion rockets, then we could mine the deuterium gas in the atmosphere of Jupiter and Saturn as fuel. But that is another great adventure altogether.
Isn't the Mars atmosphere really thin though? (Or am I mis-remembering.) Suggesting mining Argon from Mars atmosphere might be a bit difficult.
The Mars atmosphere is thin (about 1% density of Earth's atmosphere), but even that would not pose much of a problem: you just would need to pump gas in longer, that's all. By the way, did you catch the news about a deep penetrating radar on Mars Express having detected a 20-kilometer wide liquid water lake some 1.5 km under the south pole of Mars?
Sorry, I am a bit of a computer dinosaur and don't know how to create a link with another site. It is however big news and you should be able to read it on CNN, BBC or other major news site. The scientists believe that the water underground is liquid because it had a high salt concentration, being basically like brine. That is something that I was expecting/hoping for years already.
I am all for nuclear-thermal engines, since they would rely on hydrazine for fuel. That way you could refuel your ship between Earth, the Moon, and Mars using outposts that harvest ices. This is abundant in the polar regions of the Moon and Mars, not to mention in underground sources.But of course, this infrastructure would require an outpost on the lunar surface, a lunar orbital habitat, and the same on and around on Mars.
Michel wrote: "Sorry, I am a bit of a computer dinosaur and don't know how to create a link with another site. It is however big news and you should be able to read it on CNN, BBC or other major news site. The sc..."I believe you are referring to this news source, which I was alluding to in that previous post:
http://sci.esa.int/mars-express/60516...
I've read all your interesting posts. I wonder what you think are the chances of getting government funding for further space exploration. This doesn't seem to be on the current agenda. Or will it be privately funded?
Unfortunately, I don't see any interest for extra funding of space programs in Washington. As for private funding, the needs would be in the tens of billions of dollars per year. So, I am not too optimistic.
Scout wrote: "I've read all your interesting posts. I wonder what you think are the chances of getting government funding for further space exploration. This doesn't seem to be on the current agenda. Or will it ..."Well, the current budget environment is not too encouraging, but there's some real hesitation to slash funding for NASA's space exploration programs, given their popularity and the important role they play. Before Trump took office, GOP congressmen moved quick to secure transitional funding for the "Journey to Mars", and its been continued, even though Trump's admin has shifted the priorities clumsily.
Don't know about colonizing, but today's lunar eclipse is pretty nice. Anybody's watching?
Nik wrote: "Don't know about colonizing, but today's lunar eclipse is pretty nice. Anybody's watching?"I slept in, but it would not have mattered. Whenever there is anything interesting astronomical here luck seems to bring on the clouds. :-(
Nik wrote: "Don't know about colonizing, but today's lunar eclipse is pretty nice. Anybody's watching?"Got up at 4.30am, only to discover a completely cloudy sky...
Apparently it's good for tonight too. (2nd Chance)
A friend and I were talking about how we might go about terraforming the Moon. Basically, he said, we shouldn't! But transforming parts of it is entirely doable, especially around the polar regions where there's abundant water ice and we could build domes directly over the craters. 
It's called paraterraforming, and involves creating Earthly-habitats within enclosed areas on a planet (or even around an entire planet). The cool thing is that this would work for Mercury too, which also has permanently-shaded and cratered polar regions with abundant ice.
Added a photo to the group's gallery for those who wanted to see the blood moon, but didn't have cloud dispersing rockets -:)
Matthew wrote: "A friend and I were talking about how we might go about terraforming the Moon. Basically, he said, we shouldn't! But transforming parts of it is entirely doable, especially around the polar regions..."
Paraterraforming is, in my mind, the future of Humanity in space. Underground (in natural caverns) or under surface ice habitats would be ideal to protect from the radiations that bathe most celestial bodies in the Solar System. Prefabricated habitats sunken under the ice of Jovian moons and anchored in place by steel cables would provide total protection against both radiations and extremes of temperature. As for the excess heat from these habitats (as someone objected earlier on), simple radiators sticking out in the cold surface of the moon should be able to evacuate it.
Once those habitats would be in place and pressurized, you could then do pretty well anything you wanted inside, as long as the structure(s) is large enough, while the ice surrounding it would provide both the water and oxygen necessary for its occupants.
Paraterraforming is, in my mind, the future of Humanity in space. Underground (in natural caverns) or under surface ice habitats would be ideal to protect from the radiations that bathe most celestial bodies in the Solar System. Prefabricated habitats sunken under the ice of Jovian moons and anchored in place by steel cables would provide total protection against both radiations and extremes of temperature. As for the excess heat from these habitats (as someone objected earlier on), simple radiators sticking out in the cold surface of the moon should be able to evacuate it.
Once those habitats would be in place and pressurized, you could then do pretty well anything you wanted inside, as long as the structure(s) is large enough, while the ice surrounding it would provide both the water and oxygen necessary for its occupants.
Michel wrote: "Matthew wrote: "A friend and I were talking about how we might go about terraforming the Moon. Basically, he said, we shouldn't! But transforming parts of it is entirely doable, especially around t..."Interesting point. There have been proposals for building habitats within Europa's ice shell because of the recesses that are believed to exist there. One proposal came from the Artemis Project, which involved establishing a base on the surface, drilling down into a pocket in the ice, and then establishing the habitat there.
http://asi.org/adb/06/09/03/02/110/eu...
Michel wrote: "Matthew wrote: "A friend and I were talking about how we might go about terraforming the Moon. Basically, he said, we shouldn't! But transforming parts of it is entirely doable, especially around t..."How will we deal with the impact of living permanently in a low gravity environment on our bone formation (future medicine? DNA? ???)
I actually imagined for my latest novel an easy, low-cost way to fight the effects of low gravity on the human body: a so-called 'fat suit'. Basically, it would be a simple coverall with multiple pockets all over it, with the pockets containing heavy flexible pads. Those pads would be distributed around the coverall (especially around or near joints) and their extra weight would compensate the lightness felt by humans living in low gravity. The coveralls could have velcro tightening bands to prevent it from floating/shifting over the body and each person would get a specific total weight in pads (possibly containing lead wires woven into patches) to make him feel like on Earth while he/she works or go around. The lead-linen pads would also have the extra advantage of giving some protection against accidental radiation exposure.
Graeme wrote: "Michel wrote: "Matthew wrote: "A friend and I were talking about how we might go about terraforming the Moon. Basically, he said, we shouldn't! But transforming parts of it is entirely doable, espe..."That is a very good question, and one which NASA is investigating with keen interest. Right now, their main concern is how astronauts will fare with microgravity during the long-duration trip to Mars, not to mention the time they spend on Mars where the gravity is roughly 37% Earth normal. For more info on how they are researching the long-term effects, check out the Twin Study:
https://www.nasa.gov/twins-study
As for what we could do about it for colonists, that isn't quite yet clear. But the smart money says we'll have to lean pretty heavily on advancements in bio-medicine to ensure that people's bone density, muscles and organs don't deteriorate.
Seems like a reasonable idea. A variation on weight belts used by extreme athletes.
Graeme wrote: "What about pregnancy and early life?"Also a good question! Basically, grown people can always spend time in the centrifuge or the resistance machine. But we have no idea how fetuses and children will deal with exposure to lower gravity. Again, we can only assume that some kind of medical treatments will be devised that can address this. But of course, it would help if we knew the actual effects that being born into lower-g or microgravity would have.
Affects: Poor bone formation, I would imagine.
Mind you, solving that problem would probably also solve osteoporosis issues in the aged.
Graeme wrote: "Mind you, solving that problem would probably also solve osteoporosis issues in the aged."Indeed! Space-based research always has led to medical and commercial advances here on Earth. And I imagine there will be experiments conducting aboard the ISS in the not-too-distant future (or perhaps on the Moon) to see how fetal animals grow in microgravity or 15% Earth normal gravity. I also suspect the solution will involve nanotechnology or gene therapy of some kind.
That being said, there's also the possibility that pregnant women will be encouraged to return to Earth for the entire period of their pregnancy and the child's early life. I smell a story idea... :)
Matthew wrote: "I also suspect the solution will involve nanotechnology or gene therapy of some kind..."Likely pathways to solutions. The thing is, I fully expect a solution, a way will be found to manage this specific problem.
I have faith in human ingenuity. (one of my few faiths...)
Matthew wrote: "Also a good question!..."I'm full of good questions. It comes from believing less than half of what I know, and knowing less than half of what I believe.
We do already know that astronauts have a variety of physical issues on their return to earth - and when you consider that even in the long term, we're only talking three to six months usually, that leads to wondering about longterm issues.Wikipedia has quite an interesting pile of info (referenced).
https://en.wikipedia.org/wiki/Effect_...
https://www.theregister.co.uk/2018/03...
You say some quotable things, Graeme. I'm full of questions, too. What about Michel's fat suit idea?
My quote above is a joke based on what Bilbo says at his 111th birthday party....Michel's fat suit idea seem reasonable, but only once on a planet sized body like Mars, and as I pointed out, might be problematic for a developing fetus or child.
Graeme wrote: "My quote above is a joke based on what Bilbo says at his 111th birthday party....
Michel's fat suit idea seem reasonable, but only once on a planet sized body like Mars, and as I pointed out, migh..."
I can see a possibility for the case of pregnant women and developing fetus. While my 'fat suits' could be worn by people on or under the surface of a planet or moon, pregnant women could spend their months of pregnancy aboard a large orbital station equipped with contra-rotating carrousels. Those carrousels would provide full Earth gravity to its occupants if large enough and turning at the right speed (a 200 meter diameter carrousel turning at about 3.5 rpm would do the trick). Since that station would turn around the planet/moon, it would be quick and easy to get to from the surface and could be armored against space radiations. A variant solution for truly small moons with little felt gravity would be to build bases within them that are in essence giant carrousels. But I am sure that plenty of ideas will come out to solve all these problems in time.
Michel's fat suit idea seem reasonable, but only once on a planet sized body like Mars, and as I pointed out, migh..."
I can see a possibility for the case of pregnant women and developing fetus. While my 'fat suits' could be worn by people on or under the surface of a planet or moon, pregnant women could spend their months of pregnancy aboard a large orbital station equipped with contra-rotating carrousels. Those carrousels would provide full Earth gravity to its occupants if large enough and turning at the right speed (a 200 meter diameter carrousel turning at about 3.5 rpm would do the trick). Since that station would turn around the planet/moon, it would be quick and easy to get to from the surface and could be armored against space radiations. A variant solution for truly small moons with little felt gravity would be to build bases within them that are in essence giant carrousels. But I am sure that plenty of ideas will come out to solve all these problems in time.
I think that is precisely what you need, and given that any habitat in the system is likely to have a "way station," nearby, as space craft might be built to "never land,"
World, Writing, Wealth
Books mentioned in this topic
Entering Space: Creating a Spacefaring Civilization (other topics)The Case for Mars (other topics)
