New luna images raining on the water parade

[barrykirk]

Instead of LOX Aluminum...<br /><br />Are there any solid propellants that can be manufactured from lunar materials?<br /><br />Aluminum and Oxygen are common.<br /><br />What are the materials that the moon is lacking.<br /><br />1) Hydrogen<br />2) Nitrogen ( Not Sure )<br />3) Carbon ( Not Sure )<br /><br />If nitrogen is available, again I'm too lazy this morning to check that out, then ammonium perchlorate is a possibility and solid rockets become a possibility.<br /><br />A solid rocket would easily be able to do SSTO from the lunar surface.

 

[barrykirk]

Wow, just read the article on the LOX monopropellant. That sounds interesting. Although, a solid rocket does sound easier if the raw materials to make it are present.

 

[halman]

BarryKirk,<br /><br />So far, we can only say that hydrogen has not been found on the lunar surface. We have no idea what lies a few meters below the surface, because no cores have been taken at that depth. Considering the conditions on the lunar surface; intense temperature changes, vacumn, bombardment by radiation and rocks, it is unlikely that regolith is going to be completely representative of the lunar composition.<br /><br />If we were to judge the Earth's resources only by what is found on the surface, we would have a very imcomplete picture of what is available here.<br /><br />And a magnetic launcher will always be competitive with any fuels manufactured on the Moon for lowest cost to orbit, especially in the long term. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[mrmorris]

<font color="yellow">"So far, we can only say that hydrogen has not been found on the lunar surface."</font><br /><br />Not really true. Lunar Prospector found neutron ratios that indicate hydrogen-rich minerals. That might not be hydrogen in <b>water</b> -- but there is apparently something at the surface with hydrogen in it. LRO has (IIRC) three different instruments on it designed to tell us more about what that might be.

 

[willpittenger]

<blockquote><font class="small">In reply to:</font><hr /><p>a magnetic launcher will always be competitive with any fuels manufactured on the Moon for lowest cost to orbit<p><hr /></p></p></blockquote><br />If we have a decent source of lunar power. Solar cells take time to set up in any large quanities and they would only work half the time. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[halman]

mrmorris,<br /><br />Thank you for that link. The maps indicate that hydrogen exists in some form over considerable parts of the areas mapped, which surprised me. I was under the impression (derived from a Wikipedia article apparently written by a Mars First advocate about lunar colonization) that hydrogen was very scarce, if found at all, on the lunar surface.<br /><br />This discussion points up how difficult it is to accurately interpret data about anything based entirely upon remote sensing. There always seems to be contradicting data sets, which can be interpreted in the most negative ways. Until there are people on the spot, able to walk around and look, pick things up, and pry into the cracks, we will be dealing with uncertainty. The only thing that we know for sure is that we will find things that will be useful, somehow. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[halman]

willpittenger,<br /><br />I was basing my premise on the belief that any chemical processing will take energy, which would most likely come from solar power. Therefore, we would be a step further away from directly harnassing the solar energy if we use it to make chemical fuels to launch payloads off of the Moon, rather than using the solar energy to launch the payloads.<br /><br />Although collecting solar energy will initially require substantial investment in time and materials, the intensity of that energy when undiluted by an atmosphere offsets the costs. I have read that, at one AU, a square yard exposed to the Sun recieves 3 1/2 kilowatts of energy. Even though solar panels do not come any where near total conversion, and the lunar night will limit collection to half of the time, we will be able to collect huge amounts of energy compared to what we can do on Earth with the same collectors. One of our greatest challenges will be learning to store this abundance for use either during the lunar night or for portable equipment, such as tractors and excavators. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[willpittenger]

You have valid points. However, some fuels may be made from lunar regolith. Such fuels may not require as much energy to make. The energy might already be in the soil. Let the compounds react on their own and you might have fuel. The only energy spent might be simply collecting the required materials and filling the tank. That is pure speculation, but you can't rule it out. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[barrykirk]

A magnetic launcher may indeed be cheaper and easier for cargo, but building one that can launch people is going to take a lot of resources.<br /><br />A rocket does have the advantage that it can spread it's thrust out for a long enough period of time that it doesn't pulp the astronauts.

 

[halman]

BarryKirk,<br /><br />So far, I have read numerous reasons why the Moon is going to be a poor location for a colony. Personally, I don't see large amounts of human traffic to or from the Moon for at least 100 years. But I do believe that there will a lot of material launched from the Moon, to support zero-gravity manufacturing. Now, if a low cost propellant were discovered that could be manufactured from Lunar regolith, that would change a lot of things, but probably still not the number of people going to the Moon. If water ice is found at the lunar poles, launching it from there might prove to be more expensive than transporting it to a lunatron set up on one of the maria.<br /><br />Eventually, the Moon will probably be a popular tourist destination, but, considering the rate that the private sector launch companies are advancing, I don't forsee any large scale tourism beyond sub-orbital for quite some time. I had sincerely expected a successful launch by one of those companies, especially Falcon, by now. I guess that we need to remember the early days of the Arianne, which were not very encouraging. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>

 

[PistolPete]

There may not be many large colonies on the moon but there will probobly be at least one or two small permanently manned colonies (one on each pole perhaps) for operating and maintaining the He3 extraction equipment. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[PistolPete]

Oh, I just thought of another reason for having polar lunar colonies. If He3 extraction becomes a reality, then it will have to be stored somewhere. Why waste energy trying to keep He3 cryogenic, when you could just put them at the bottom of Shackleton crater. It would be easier than burying them, anyway. <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[thinice]

<i>It would be easier than burying them, anyway.</i><br /><br />I wonder who are "them"? <img src="/images/icons/rolleyes.gif" />

 

[halman]

thinice,<br /><br />All them He3 critters that they want to harvest at the goalposts of the Moon. <div class="Discussion_UserSignature"> The secret to peace of mind is a short attention span. </div>