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Sintered Regolith

2011-10-10T14:33:45Z

JMajor34: None

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[[image:MLS1_Brick.GIF|thumb|A brick of MLS-1 basalt sintered at 1100 degrees Celsius for 2 hours. Click to Enlarge]]
Sintered [[regolith]] falls into the category of ceramic materials as sintering is the process most common to ceramics. When bricks are made from clay on Earth, first the bricks are heated long enough and hot enough to drive out the water. Then the heating is increased to cause partial melting or vitrification which results in the edges of adjacent grains being bonded together once they have cooled. The unmelted particles provide a stable shape and size during the process which involves some shrinkage and a decrease in porosity.

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==Lunar Considerations==
On Luna water for mixing the various particles would be very expensive and recycling the water would never be 100% effective. It has been demonstrated that the sintering of dry regolith simulant will provide satisfactory bricks, and there is the example of mixing dry powders for [[powder metallurgy]], which is a sintering process performed on Earth and involves putting the material under pressure. Compaction of lunar simulant using vibration has been [http://ares.jsc.nasa.gov/HumanExplore/Exploration/EXLibrary/DOCS/EIC049.HTML demonstrated] by NASA, but this method may not be as effective or may require more time in the reduced gravity of the moon. More will be known about the quality of bricks possible from lunar materials when the research can be done on Luna. A possibility to consider is the [[Sintered Brick Construction|sintering of bricks]] in an oxygen atmosphere as opposed to in a vacuum. Fine particles in an insulating vacuum have the tendency to stick together due to friction which generates a static charge between adjacent, non-conducting particles. Sintering regolith in an oxygen atmosphere has the potential to provide an atmospheric ground but may also result in a loss of oxygen due to oxidation. However, oxygen is plentiful on Luna and experimentation will show if there is benefit to balance the cost. Some low partial pressure of oxygen could conceivably be found best for the process of sintering bricks. Another alternative is the use of a hydrogen atmosphere which results in a net gain of oxygen and will be discussed later.

==Radiant Heating==
Experiments in radiant heating of regolith simulant have been carried out by NASA Johnson Space Center and Lockheed Engineering & Sciences Co. [http://www.nss.org/settlement/spaceresources/1998-InSituResourcesForConstructionOfPlanetaryOutposts.pdf Results] show that radiant heating can reproducibly sinter large, strong bricks in a fused silica mold. Fused silica was chosen for its combination of extremely low thermal conductivity and low density.

Uniform bricks measuring 7.9 x 5.5 x 3.6 cm were produced by heating [[MLS-1]] [[Basalt]] for two hours at 1,100 degrees Celsius. Resulting bricks were crack free except for small expansion cracks near the top surface, with negligible reductions in volume and density.

Larger bricks were produced from the glass-rich simulant [[JSC-1]]. The sample was initially compacted using vibration for 5 minutes until reaching 2.45 grams/cm3, and then sintered for 2.5 hours at 1,100 degrees Celsius. A silica fabric liner was inserted between the simulant and the fused silica mold to prevent the brick from sintering to the mold.

==Microwave Heating==
In experiments, pure microwave heating has been unsuccessful in producing usable bricks. Due to the thermal insulating properties of crushed lunar regolith and it's simulants, the insides of the bricks melt while the outside remains [http://www.thoughtmechanics.com/ web design service in atlanta] unsintered. While not useful for this purpose, microwave heating may be found useful for foundation preparation, permanent grading, road construction, dust remediation, and applications for which molten regolith is required.

[[image:MLS1_Brick_cross_section.GIF|left|thumb|An electron micrograph of a cross section of sintered MLS-1 basalt brick, showing bonding at grain to grain contacts. Click Image to Enlarge.]]

==Hybrid Microwave Sintering==
Research conducted by NASA Johnson Space Center and Lockheed Engineering & Sciences Co. has indicated that the lunar simulant [[MLS-1]] can be successfully sintered using a [http://ares.jsc.nasa.gov/HumanExplore/Exploration/EXLibrary/DOCS/EIC049.HTML combination] of both microwave and radiant heating.

The crucible was surrounded by silicon carbide bricks, which converted part of the 2.45GHz microwave energy to heat. This radiant heating kept the outside of the regolith hot while microwaves heated the inside at the same temperature of 980 degrees Celsius for 35 minutes. Microwave power was then slowly reduced over several hours. The result was an evenly heated and cooled sintered block with no fractures capable of withstanding up to approximately 1,100 psi.
===Oxygen Retrieval and Magnetic Handling===
Hybrid microwave sintering in a flowing [[hydrogen]] atmosphere resulted in the reduction of [[iron oxide]] to produce [[iron]] in the sample and [[water]] which escaped as vapor. This additional process provides a means of [[oxygen|oxygen retrieval]] as well as increasing the iron content so that bricks can be lifted using a magnet.

==External Links==
*[http://www.lpi.usra.edu/meetings/LPSC99/pdf/1562.pdf Construction Materials for Planetary Outposts: A Review - LPI] .. PDF
*[http://isru.msfc.nasa.gov/lib/Documents/PDF%20Files/Final_LSRM_Report_12-9-05.pdf Lunar Regolith Simulant Materials: Recommendations for Standardization, Production and Usage - NASA MSFC] .. PDF
*[http://www.permanent.com/i-sinter.htm Sintering of Lunar and Asteroidal Material - PERMANENT]
*[http://coewww.rutgers.edu/~benaroya/publications/Ruess%20et%20al%20ASCE%20JAE.pdf Structural Design of a Lunar Habitat - Journal of Aerospace Engineering, July 2006, pg 137] .. PDF
*[http://www.nss.org/settlement/spaceresources/1998-InSituResourcesForConstructionOfPlanetaryOutposts.pdf Workshop on using In-Situ resources for construction of planetary outposts - LPI] .. PDF
*[http://ares.jsc.nasa.gov/HumanExplore/Exploration/EXLibrary/DOCS/EIC049.HTML Sintering Bricks on the Moon - NASA JSC]
*[http://gsfctechnology.gsfc.nasa.gov/Cardiff.pdf Vacuum Pyrolysis and Related ISRU Techniques - NASA GSFC] .. PDF

Architecture as Tent City

2011-10-10T14:33:12Z

JMajor34: None

[[Image:MLOFacilityAdvanced01.jpg|frame|MLO Facility at Advanced Stage]]

 

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 Architecture as Tent City 

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In 1989 the USA discussed returning to the [[Moon]]. At that time, the idea failed over the high estimated price. However many useful paper studies were done then that can be of value to us now. One of these described a Manned Lunar Outpost (MLO) as a tent city.

==Reference==

A detailed study of a Manned Lunar Outpost can be found on the Web at:

[http://www.spaceref.co.jp/images/manned_lunar_outpost.pdf, The Manned Lunar Outpost (MLO): a NASA/USRA-Sponsored Study]

==Technical Description==

The MLO is made from modules shipped from Earth with an unmanned heavy lift vehicle (HLV). The modules are based on designs of similar modules with a service history in a space station in low Earth orbit.

===Modules===

The individual habitat modules are sized to fit the bulbous shroud of the HLV. They are also limited in mass to that which the HLV can deliver to the surface of the Moon.

Some of the modules are fixed in size and can be connected end to end to make larger structures. These are strong enough that they can be buried in several meters of lunar [[regolith]] to provide thermal and radiation protection.

Some of the modules have an accordion fold center section of fabric that allows them to be deployed into long building sections. These modules provide a lot of floor space for activities like [[agriculture]], but cannot be deeply buried for radiation protection.

===General Tenting===

One of the most striking innovations in this MLO design is the use of tents over [http://thoughtmechanics.com/ web design company atlanta] the modules to provide thermal, micrometeorite, and limited radiation protection. The tent material will be strong synthetic cloth with an aluminized coating. Several layers of tent material will be needed with spaces between them.

A small meteorite would hit the top layer of material and explode. Here it is critical to understand that meteorites act like small explosions and not like bullets. The blast debris will then expand out and hit the next layer with less force. Penetration through even a few layers to breach the habitat air bladder would be very unlikely.

The multi layers of the tent will also average out the changes in surface temperature. They will both block direct sun and reduce heat loss at night.

[[Image:MLOHabitationScienceComplex02.jpg|frame|MLO Habitation/Science Complex]]

===Heavy Tents===

A few of the heavy walled modules will be completely surrounded with one layer of heaver tent material and the space between the module wall and the tent filled in with lunar regolith. These modules will provide the crew with full radiation protection during solar storms.

==Design Problems==

This MLO design does have a number of design concerns that we will have to address:

; Limited radiation protection in the tent only modules: Aside from the solar storms, the background radiation on the surface of the Moon is harsh enough to be a concern for long term exposure.

; The thermal environment is not specified: One of the most difficult things to do on the Moon is to keep people and equipment cool at the end of the day. Rejecting excess heat is a major design problem not addressed in this study.

Also the report is dated in some ways such as references to [[Space Station Freedom]] and all the Moon people being men. These can be addressed easily.

==External Links==
*[http://hitf.jsc.nasa.gov/hitfpub/main/index.html NASA Hypervelocity Impact Technology Facility.]

----

[[Category:Architecture]]

Lunar Architecture

2011-10-10T14:32:51Z

JMajor34: None

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== Introduction ==
The architecture used on Luna will be quite different from that used in terrestrial applications. Lower gravity, high vacuum, radiation, meteorites, [[moonquake|moonquakes]], and dust control will all play large parts in the design of lunar structures. Due to this, a large number of architectural designs have been put forward for human rated habitats on Luna.

== Major Design Criteria ==

=== Atmosphere ===
(see also [[Lunar Settlement Artificial Atmosphere]], [[Roof Support]])

Any lunar habitat designed for human use must provide a breathable atmosphere and maintain proper carbon dioxide, temperature, and humidity levels. There are a number of methods proposed for achieving this, as well as number of proposals for suitable gas mixtures and pressures, as well as designs for containing a pressurized environment in the lunar vacuum.

=== Thermal Protection ===
The lack of an atmosphere on the moon, together with the extreme duration of the lunar day/night cycle, leads to large temperature extremes. A lunar habitat would need to provide a reasonably constant temperature inside.

The most commonly proposed solution to this problem is a blanket of lunar regolith piled over the habitat. Lunar regolith has extremely low thermal conductivity, and as little as a few inches would protect the habitat from any temperature swings that would be experienced outside<ref name='Lindsey'>Lindsey, Nancy J. [http://www.rcktmom.com/njlworks/LunarRegolithPprenvi2.html Lunar Station Protection: Lunar Regolith Shielding]. International Lunar Conference 2003</ref>. This solution has an advantage in that lunar regolith is readily available anywhere on the moons surface. The downside is that moving a sufficient amount of regolith to cover a lunar structure would require construction equipment on site, which may not be available for an initial lunar base attempt.

More conventional insulation could be used in this case as well. Due to the vacuum conditions on the moons surface, a reflective coating applied to the surface of the habitat would provide reasonably good thermal protection, functioning in a similar manner to a thermos. This coating would reflect solar radiation during the day, and preventing radiation of internal heat at night. Multiple reflective baffles installed at the surface would increase the effect. To date, this approach has been utilized on all lunar missions, all of which took place during the lunar day and near the equator.

Even if the insulation was sufficient to block out the temperature variations, some additional cooling would be required, as energy would be continuously be generated within the habitat from electrical equipment and the metabolic processes of the inhabitants. Insulation sufficient to block out heat from outside would, on the same token, keep heat inside. A series of external radiators, suitably placed so as to be out of the sun during the day, could provide the necessary cooling.

=== Meteorites ===
A lunar habitat would need to be protected from meteorite impacts. This requirement is similar to the requirements already in place on orbital structures such as the ISS. One significant difference is that orbital structures have a certain amount of maneuvering capability to dodge incoming debris, while a lunar habitat does not. As such lunar structures have more stringent requirements than orbital structures for impact protection.

The solution to this problem most commonly suggested is the same as for thermal protection, namely, a blanket of lunar regolith. This blanket would need to be thicker than what is required for thermal protection, though a thickness of less than half a meter is considered to be sufficient<ref name='Lindsey'> </ref>. This again carries the requirement of having construction equipment on site.

Other shielding technologies could be utilized to provide sufficient meteorite protection. Inflatable spacecraft designs in particular show promise in this regard. Bigelow aerospace is developing a line of these structures, a derivative of the cancelled NASA TransHab project. Bigelow has already flown two prototypes of this technology, and intends to construct a privatelly owned space station with them, as well as an eventual moonbase. The company claims that the meteorite shielding material built into its modules is sufficient for this purpose.

=== Radiation ===
One of the more difficult problems facing design of a lunar habitat is protection from solar and cosmic radiation. The moon, being outside the earths magnetic field, receives this radiation directly. Of particular importance is the effect of solar storms, a single one of which would provide sufficient radiation to kill an unprotected person.

The regolith blanket proposed as protection from thermal and meteorite hazards could also serve the third function of radiation protection, given sufficient thickness. How thick this shield would need to be is a matter of some debate, as the exact level of safe radiation is not entirely agreed upon. To reduce the radiation levels received to current NASA standards for its astronauts, a thickness of 1-2 meters appears to be sufficient<ref name="Lindsey"> </ref>. If earth-like levels are desired, then 3-5 meters would likely be needed. The exact thickness is not precisely known, due to the differences between cosmic radiation and the nuclear radiation most shielding science is designed to protect against, and most likely will remain an educated guess until a more in-depth field study is made.

If equipment for moving a sufficient amount of lunar regolith is not available on site (an early base construction attempt for example), providing sufficient shielding is difficult matter. One option is to site the base in of the the permanently shaded polar [http://www.thoughtmechanics.com/ web design atlanta ga] craters, where solar storms would not reach. Another is to provide a "storm cellar" of sorts, a small room in the habitat which is heavily shielded against radiation, which the crew could retreat into in case of a solar storm. As this room would only need to be big enough to hold the crew until the radiation levels dropped back to normal, its construction and shipping to the base site would be much simpler than shielding the entire habitat, which could make it a viable solution for an early base attempt.

=== Moonquakes ===
(see main article: [[Moonquake]])

Moonquakes are moderately powerful (by earth standards) seismic events which can last for over ten minutes. Habitats placed in areas where moonquakes occur will need to be sufficiently strong/flexible to withstand the shaking without buckling or leaking atmosphere.

== Proposed Designs ==
;[[Architecture as Mole Hills]]: The living space could be inflated structures buried in trenches.

;[[Architecture as Tent City]]: We could use tents to protect inflated living space.

;[[Architecture in Field Stone]]: The loose rocks of the Moon could provide the needed thermal and radiation protection.

==See Also==
*[[Meteor Hazards]]
*[[Radiation Problem]]
*[[Roof Support]]
*[[Power for Settlements]]
*[[Site Selection]]
*[[Slopes]]

==References==
<references/>

[[Category:Architecture]]

List of Lists

2011-10-10T14:32:34Z

JMajor34: None

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The primary purpose of this list is to generate lists of articles that are needed [http://www.thoughtmechanics.com/ web design atlanta georgia] by Lunarpedia. You can start a missing list or investigate or work on an existing list of needed articles. Please to not hesitate to add list ideas to this list or article ideas to the appropriate lists linked to from here.

...or start the article or work on improving an existing article...

Existing but empty list articles should be found [[:Category:Unimplemented Lists|here]]. Please avoid creating more empty lists.

=='''A'''==
[[List of Academia]] 
[[List of Advanced Composites]] 
[[List of Agricultural Pollinators]] 
[[List of Agricultural Products]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Agricultural_Products|here]] 
[[List of Agricultural Technologies]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Agricultural_technologies|here]] and [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Horticulture_-_homestead_gardening|here]] 
[[List of Analog Station Efforts]] 
[[List of Analog Station Designs]] 
[[List of Apollo Astronaut Crews]] 
[[List of Apollo Sites]] 
[[List of Apollo Spacecraft]] 
[[List of Architectural Concepts]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Lunar_Architecture|here]] 
[[List of Areas of Research]] -- see [[Lunarpedia:Outline draft/UNIVERSITY OF LUNA|here]] 
[[List of Arts and Crafts]] -- see [[Lunarpedia:Outline_draft/HEALTHY_CITIZENS#Lunar_Appropriate_Arts_.26_Crafts|here]] and [[Lunarpedia:Outline_draft/UNIVERSITY_OF_LUNA#Lunar_Appropriate_Arts_.26_Crafts_research|here]] 

=='''B'''==
[[List of Base Concepts]] 
[[List of Biosphere Technologies]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Biosphere_technologies|here]] 
[[List of Books]] 
[[List of Boosters]] 
[[List of Business Models]] 

=='''C'''==
[[List of Component Vendors]] 
[[List of Conferences and Conventions]] 
[[List of Construction Materials]] 
[[List of Commissions, Reports, Studies]] 


=='''D'''==
[[List of Discontinued and Cancelled Boosters]] 

=='''E'''==
[[List of Elements]] 
[[List of Equations]] 
[[List of Export Markets]] -- see [[Lunarpedia:Outline_draft/TRADE_AND_THE_BOTTOM_LINE|here]] 
[[List of Exports]] -- see [[Lunarpedia:Outline_draft/TRADE_AND_THE_BOTTOM_LINE|here]] 
[[List of Electrical Considerations]] 

=='''G'''==

[[List of Gemini Astronauts]] 
[[List of Gemini Spacecraft]] 
[[List of Google Lunar X PRIZE Teams]] 

=='''H'''==
[[List of Habitat Concepts]] 
[[List of Health and Fitness]] -- see [[Lunarpedia:Outline_draft/HEALTHY_CITIZENS#Health_and_Fitness_in_a_1.2F6th_G_environment|here]] 
[[List of Historical Articles]] 
[[List of Human Resources]] -- see [[Lunarpedia:Outline_draft/UNIVERSITY_OF_LUNA#Human_Resources_research|here]] 

=='''I'''==
[[List of Import Markets]] -- see [[Lunarpedia:Outline_draft/TRADE_AND_THE_BOTTOM_LINE|here]] 
[[List of Imports]] -- see [[Lunarpedia:Outline_draft/TRADE_AND_THE_BOTTOM_LINE|here]] 
[[List of Industrialization Articles]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Lunar_Industry|here]], [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Industrial_Diversification_Strategies|here]], and [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Cottage_Industries|here]] 
[[List of Infrastructure Considerations]] 
[[List of ISRU|List of In-situ Resource Utilization Methods]] 

=='''L'''==
[[List of Launch Sites]] 
[[List of Launch Systems and Vendors]] 
[[List of Launch System Vendors]] 
[[List of Lighting Technologies]] 
[[List of Logistical Considerations]] 
[[List of Lunar Based Sciences]] -- see [[Lunarpedia:Outline_draft/HEALTHY_CITIZENS#Astronomy_from_the_Moon|here]] and [[Lunarpedia:Outline_draft/UNIVERSITY_OF_LUNA#Astronomy_and_S.E.T.I.|here]] 
[[List of Lunar Tourism]] -- see [[Lunarpedia:Outline_draft/PRELUDE#Lunar_Tourism|here]] 

=='''M'''==
[[List of Major Settlement Challenges]] -- see [[Lunarpedia:Outline_draft/WHERE_TO#Major_Challenges_to_Settling_the_Moon|here]] 
[[List of Maps]] 
[[GFDL:List of maria on the Moon|List of Maria]] 
[[List of Mercury Astronauts]] 
[[List of Mercury Spacecraft]] 
[[List of Mining Engineering Concepts]] 
[[List of Mission Designs and Options]] -- not presently existing reference missions to design 
[[List of Modules]] 
[[List of Movies]] 
[[List of Museums]] 

=='''N'''==
[[List of Nonterrestrial Sources]] -- see [[Lunarpedia:Outline_draft/TRADE_AND_THE_BOTTOM_LINE|here]] 

=='''O'''==
[[List of Observation guides]] -- see [[Lunarpedia:Outline_draft/PRELUDE#Understanding_what_you_see|here]] and [[Lunarpedia:Outline_draft/PRELUDE#Observing_the_Moon|here]] 
[[List of Online Resources]] 
[[List of Organic Product Substitutes]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Substitutions_for_organics.2C_synthetics|here]] 
[[List of Organizations]] 
[[List of Outpost Activities]] -- see [[Lunarpedia:Outline_draft/BREAKOUT_AGENDA|here]] 
[[List of Outpost Concepts]] 

=='''P'''==
[[List of People]] 
[[List of Performing Arts]] -- see [[Lunarpedia:Outline_draft/HEALTHY_CITIZENS#Lunar_Appropriate_Performing_Arts|here]] 
[[List of Planned Missions]] 
[[List of Political Requirements for Colonies]] -- see [[Lunarpedia:Outline_draft/UNIVERSITY_OF_LUNA#Lunar_Frontier_Political_Science|here]] 
[[List of Proposed Metal Production Methods]] 
[[List of Propulsion Systems]] 
[[List of Offworld Medical Risks]] 
[[List of Publications]] 

=='''R'''==
[[List of Recreation]] 
[[List of Resource Development Articles]] -- see [[Lunarpedia:Outline_draft/BREAKOUT_AGENDA#ISRU_-_development_of_local_resources|here]] 
[[List of Resources]] 
[[List of Reusable Spacecraft]] 
[[List of Robotic Missions]] -- see [[Lunarpedia:Outline_draft/PRELUDE#Economic_Geography:_chemical.2C_mineralogical.2C_and_topographic_resources|here]] 
[[List of Robots]] 

=='''S'''==
[[List of Satellite Articles]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Lunar_Service_Satellite_systems|here]] 
[[List of Selenological Articles]] -- see [[Lunarpedia:Outline_draft/UNIVERSITY_OF_LUNA#Selenology_.28Lunar_geology.29|here]] 
[[List of Settlement Business Ideas]] -- see [[Lunarpedia:Outline_draft/THE_RETURN#Making_Money_at_the_Outpost|here]] 
[[List of Settlement Locations]] -- see [[Lunarpedia:Outline_draft/HEALTHY_CITIZENS#Scattered.2Fmultiple_sites_for_new_settlements|here]] 
[[List of Shielding Options]] -- see [[Lunarpedia:Outline_draft/THE_RETURN#Shielding_Options|here]] 
[[List of Site Management Issues]] -- see [[Lunarpedia:Outline_draft/THE_RETURN#Site_management_issues|here]] 
[[List of Soviet Cosmonaut Crews]] 
[[List of Space Facilities]] 
[[List of Space Station and Module Companies]] 
[[List of Standards]] 

=='''T'''==
[[List of Technical Terms]] 
[[List of Time Issues]] -- see [[Lunarpedia:Outline_draft/HEALTHY_CITIZENS#Lunar_Calendar_-_Moon_Rhythm_Scheduling|here]] 
[[List of Transportation Systems]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Surface_transport|here]] and [[Lunarpedia:Outline_draft/UNIVERSITY_OF_LUNA#Transportation_technology|here]] 

=='''U'''==
[[List of Unmanned Sites]] 
[[List of Urban Planning]] -- see [[Lunarpedia:Outline_draft/SETTLEMENT_GROWTH#Urban_Systems|here]] 

=='''V'''==
[[List of Vendors]] 

[[Category:Bootstrap lists]]