Space flight and interplanetary travel

[holmec]

With the future advent of a human Mars mission, we will be embarking on a new skill (if not many). Specifically speaking the skill of interplanetary but intra solar system travel.<br /><br />There are problems with such travel that we avoid in our LEO missions. Such as:<br />Prolonged exposure to radiaton<br />Limits on acceleration due to human factors<br />Conservation of resources - mainly oxygen/carbon dyoxide , food, water, and yes even feces managent.<br />Propulsion - rockets, sails, ion drives, nuclear drives, microwave drives,... etc.<br />Navigation - how to get there, what are your options when (not if) things go wrong (like overshooting a planet).<br />Internal Environment - how much space to you give, how much mass is the ship and its cargo, what kind of design is appropiate.<br /><br />I would like to discuss thise on this thread, since there seems to be a belief that we could just build a space ship that will launch from earth and magically land on another planet. Hopefully this will be a learning dicussion for all.<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[grooble]

I'd say build an interplanetary Ferry, a huge ship for the earth / mars runs. It wouldn't need heat sheilding as it won't land on planets. You could put a dozen nuclear reactors in it for enourmous power.

 

[holmec]

So let me start off with the idea of acceleration through space.<br /><br />As I understand it, a propulsion system in space is mainly used for applying acceleration in a certain direction. <br /><br />On earth we are used to 1g. I saw a documentry on Science channel where a NASA researcher conducted experitments with rats in a certrafuge. The rats adapted to 2gs and I think they got up to 3gs. <br /><br />In Space flight (though we do not have the techknowlogy yet) the fastest way to go from point A to B from full stop to full stop is accelerating until the mid point and then deccelerating until stop. The question is how much acceleration can the human body live in in any given direction?<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[holmec]

true true.<br />But can you be more specific on a certain system?<br />like how do you deal with space radiation? <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[spayss]

"With the advent of a human Mars mission...'<br /><br /> What mission?<br /><br />

 

[holmec]

Well its really an intention at this point, but evetually will become a mission. The mandate to put men on Mars. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[holmec]

Ok , well I should have said "With the future advent...." <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[grooble]

I think you could have some kind of energy sheild around the ship, the hull could have some kind of devices which reflect the radiation somehow, don't know. <br /><br />Are there things which absorb radiation? <br />

 

[nacnud]

<font color="yellow">Are there things which absorb radiation? </font><br /><br />It depends on the radiation but pretty much everything absorbs radiation. For a spaceship the material has to be lightweight but still be able to stop a significant amount of radiation. The current front runners are water and polythene.<br /><br />Line an area of your ship with water filled polythene bags and you have a cost effective comparatively light weight radiation shelter.<br /><br />I wouldn’t bother with any kind of magnetic shield until a sufficiently small and powerful power source is available<br />

 

[whoa182]

I think Nanotechnology will help in this area... <br /><br />In fact, Nanotech nearly solves all of our problems <img src="/images/icons/smile.gif" />

 

[nacnud]

not with stoping ratiation is dosen't.

 

[phelan]

Hi I am new to the boards, so I hope you don't mind me just kind of jumping in with an opinion.<br /><br />Water is pretty heavy, it weighs 8lbs per gallon roughly. What about using some sort of magnetic field, would that possibly deflect the radiation?

 

[scottb50]

No. A magnetic field would have to be pretty powerful. <br /><br />No matter what, you have to take water if you take people. Why invest in other propellants when you have the most efficient at hand? Water, or specifically Hydrogen and Oxygen will do perfectly well for all of the propulsion and maneuvering needs, as well as life-support.<br /><br /><br /><br /> <div class="Discussion_UserSignature"> </div>

 

[whoa182]

well materials such as carbon nanotubes are a MUST have for future space flight. Since carbon nanotubes are now the strongeset material we have.. and might ever have. 100x stronger than pure steel, 1/6th the weight. It is required. The only problem is cost, right now they are just too expensive, but price will go down soon!<br /><br />It is also possible that we will have nanoparticles/robots or whatever they are in the future to repair damage done by radiation to people travelling. This be a good application to have onboard just incase the materials cannot withstand enormous amounts of radiation they possibly could be exposed to.<br /><br /><br />Molecule-size sensors inside astronauts' cells could warn of health impacts from space radiation. <br /><br />http://www.firstscience.com/SITE/ARTICLES/bloodstream.asp<br /><br /><br />here is an article you should take a look at:<br /><br />http://www.brightsurf.com/NASA_news_091602.html<br /><br />" A lattice of carbon nanotubes can store hydrogen at high densities, and without the need for extreme cold. So if our spacecraft of the future already uses nanotubes as an ultra-lightweight structural material, could those tubes also be loaded up with hydrogen to serve as radiation shielding? Scientists are looking into the possibility"<br /><br /><br /><br /><br /><br />

 

[grooble]

Nacnud, lets say, 20 years from now that weight is not the critical issue that it is today, that for whatever reason, launch costs have reduced dramatically.<br /><br />So what if you built a large spacecraft with something like a 10ft hull of water and polythene like you suggest, would that be sufficient?<br /><br />What would it take (which we are capable of) to make ships safe?

 

[holmec]

<I wouldn’t bother with any kind of magnetic shield until a sufficiently small and powerful power source is available><br /><br />Your right. I can only imagine the amount of energy required to produce a magnetic field to the strength of the earth's field. Which is probably the only standard we currently have that acts as a sheild. <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[grooble]

It'd be useful research though, maybe in a century you could create one around mars or the moon.

 

[holmec]

Are there other materials that can be improved upon for a shield?<br /><br />One I have a question about is plasma. We can somewhat contain plasma in a magnetic field, but can any type of plasma deflect or absorb radiation?<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[holmec]

OK. How could nano tech help in protecting a space ship from radiation? <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[grooble]

Maybe absorb it with animal fat

 

[holmec]

lol<br />you can't be serious<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[grooble]

No, i'm just curious how well organic material absorbs radiation.

 

[holmec]

one problem with using water as a propellent is that we use water to live and water weighs a lot, not to mention that we still have most of the water in the solar system here on earth and it is sparce at least elsewhere - unless the moons of Saturn and Jupiter prove to have some.<br /><br />It becomes a logistical probem.<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[holmec]

Absolutey.<br />I guess the main shiel will be for crew and any organics the crew brings along.<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>

 

[holmec]

What about lead?<br /><br />Have an outer shield of lead. Its dense and malable, so you could have different thickness for different areas on the ship.<br /><br />One sheild I overlooked is if the ship has a nuclear reactor, it would need a sheild between the reactor and the crew. The reactor has the potential of being many times deadlier than Space radiation.l<br /> <div class="Discussion_UserSignature"> <p> </p><p><font color="#0000ff"><em>"SCE to AUX" - John Aaron, curiosity pays off</em></font></p> </div>