New Mars Forums

Official discussion forum of The Mars Society and MarsNews.com

You are not logged in.

Announcement

Announcement: As a reader of NewMars forum, we have opportunities for you to assist with technical discussions in several initiatives underway. NewMars needs volunteers with appropriate education, skills, talent, motivation and generosity of spirit as a highly valued member. Write to newmarsmember * gmail.com to tell us about your ability's to help contribute to NewMars and become a registered member.

#476 2021-09-10 11:38:20

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 8,892

Re: Air. Shelter. Water. Food.

This thread and discussion has been great topic on Mars food, water supplies air and shelter

SpaceNut wrote:

giving the topic a bump as well since I am getting and error for page 10 access....

same as but error for page 20 access

Offline

#477 2021-09-10 11:47:56

Void
Member
Registered: 2011-12-29
Posts: 6,975

Re: Air. Shelter. Water. Food.

There seems to be a bump!

Actually I posted today, something I think is important Post #475.  The bump puts it out of view.  I am not sure why it was needed.

I am working on a special farming/energy/shelter/etc. method for high latitude
icy regions on Mars and maybe even Earth.


Done.

Offline

#478 2021-09-10 13:03:59

Mars_B4_Moon
Member
Registered: 2006-03-23
Posts: 8,892

Re: Air. Shelter. Water. Food.

Void wrote:

There seems to be a bump!

Actually I posted today, something I think is important Post #475.  The bump puts it out of view.  I am not sure why it was needed.

yes thank you it was an interesting post but for some reason I got an old 404 error like what happened to the thread in the past.

Let me quote what you wrote :

Void wrote:

I have revisions for the "Light Scoop". 

First, I think the thing to do is have a flat inflatable balloon that can be layed down
on top of the ice and quickly inflated with clean degassed water, and allowed to freeze.

Then a light scoop would be constructed above it, with no windows.  Rather an open
apature. 

The structure could start with a balloon of the shape for the light scoop, and will
serve as a mold. 

Water vapor would be sprayed on the south facing surfaces, but not the north where
the apature sould be.  Fibers and strengtheners can be addad as it is created.

In addition some kind of tubing embedded in the ice.  This will be to work with a
fluid such as CO2 or Ammonia + (Water ?).  Maybe something else.  This light scoop
may double as a radiator.

Ideally all surfaces when it is done will be covered in a reflective coating, or film.

The inflatable balloon for spraying on vapors will be removed and hopefull reused to
make other ones.

The balloon ice window will remain.

It is possible that a transparent film with U.V. protection may be placed over the
balloon ice window, and this could be replaced periodically as needed.  It would
not be fastened very much, and would simply lie over the balloon ice window.

-------

Concern will be needed for the weight of the structure.  Perhaps floats will have to be
placed in the water below the walls.

This plan reduces the amount of materials other than ice you need for construction, but
there still will be the desire for fibers of some kind, tubing, reflective films, and
of course the Heliostats on top of the ice and machinery to connect to the tubing,
below the ice.

So this is a solar collector and perhaps part of a heat engine which will scoop photons,
and therefore heat, into the lake, and will also, we hope be the condenser part of
a heat engine that rejects heat from the lake to the surface and the sky, and we
hope that electricity could be generated.

This should be quite good for Korolev, and also many cold high latitude locations on
Mars.

It should be well suited to utilize the midnight sun effect to collect energy and also
foster agriculture, and to also use the very low temperatures that may be expected.

-----

I actually think some version of this could be done on large ice bodies on Earth,
provided they are stable.  The northern interior of Greenland comes to mind, and
also Antarctica, in the deep interior.

If these lakes are on top of water ice, particularly on Earth, there can be concern
for the lake water falling into a crack and the lake draining down.

For Mars, the ice is colder and more stable per that risk.  There should be less
Earthquake action on Mars.  However, methods could be implemented to reduce the risk.

-Try to use 0 degC water or not much warmer.  (Remember the farming would more occur
in warm water enclosures floating in that water, or on stilts on the bottom.

Place regolith on the bottom of the lake.  This would beth serve as an insulator, and
alson weight the ice down.  The ice unless "Dirty" will be lighter than the water.

-It may be possible to attach insulating tiles to the bottom of the lake.  You would
just press them to the bottom, and they should freeze to it.  This will help keep
the ice below the tiles from warming up.  Then if a leak does form, the ice being
cold may very likely freeze any intruding liquid water and plug the crack.

*There can be other tricks, many of them.

------

This should rattle some cages:

The idea of colonizing the interior or Greenland or Antarctica may really annoy some,
but if you settled people there, they would create organic waste.  That could be dumped
on the ice, perhaps in caverns so that it does not change the albedo.  That would be
the entoomment of much Carbon, as long as the ice can be kept stable.

Recovery of nutrients may be a desire prior to entoomment.

Putting the light scoops there may actually make more surface area for cooling.  It may
be possible to net Cool the ice masses with this.  This could be important for Greenland.
I believe that Antarctica is expected to accumulate ice in the future.

------
As for both Mars and Earth, I think it could be a better thing that most people
only lived on the ice bodies during the warmer seasons, and had a place elsewhere to winter over on.  But it might be possible to make winters suitable for people.
It remains to be seen.


Done

Last edited by Mars_B4_Moon (2021-09-10 13:04:45)

Offline

#479 2021-09-10 13:28:36

Void
Member
Registered: 2011-12-29
Posts: 6,975

Re: Air. Shelter. Water. Food.

OK,

I will likely return to talk about underwater suits for bodies of water on Mars.

Done


Done.

Offline

#480 2021-09-10 18:18:26

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

Unless mars has an already existing natural underground body of water its going to be a while before man can collect enough water to create one.

The starships metal are not robust enough unless we do lots of interior bracing to make it possible for the ship to bare weight being placed onto it once laying on the ground. Of course we would require a very large ship to be moved when no cranes or other items are present on mars is as well not possible.

post and topic issues could be from the users page to display post setup in the user profile and a very old problem that we once had for when the topic got to 300 posts that it would corrupt the record table for the forum causing them to be locked before they got that large was the admin's only recourse. Which meant that repeat topics with a number was created to allow for continued discussion to occur.

here are 2 topics that are showing an error on the page, can any of you see or find what is causing them
http://newmars.com/forums/viewtopic.php?id=2039&p=6
http://newmars.com/forums/viewtopic.php?id=4918&p=5
I have my display set to 50 posts per page....

Offline

#481 2021-09-10 19:16:35

Void
Member
Registered: 2011-12-29
Posts: 6,975

Re: Air. Shelter. Water. Food.

As is typical your scope does not apply to mine.

Actually water is gathered in massive ice bodies in many places on Mars.

In the case of Korolev crater and some other places, there is a good chance that much could be achieved with more mercy in some of those locations.

https://en.wikipedia.org/wiki/Korolev_(Martian_crater)
Quote:

Korolev is an ice-filled impact crater in the Mare Boreum quadrangle of Mars, located at 73° north latitude and 165° east longitude. It is 81.4 kilometres (50.6 mi) in diameter[1] and contains about 2,200 cubic kilometres (530 cu mi) of water ice, comparable in volume to Great Bear Lake in northern Canada.[2] The crater was named after Sergei Korolev (1907–1966), the head Soviet rocket engineer and designer during the Space Race in the 1950s and 1960s.[2]

Korolev crater is located on the Planum Boreum, the northern polar plain which surrounds the north polar ice cap, near the Olympia Undae dune field. The crater rim rises about 2 kilometres (1.2 mi) above the surrounding plains. The crater floor lies about 2 kilometres (1.2 mi) below the rim, and is covered by a 1.8 kilometres (1.1 mi) deep central mound of permanent water ice, up to 60 kilometres (37 mi) in diameter.[2]

But yes if you light a fire, you do not just throw big logs in a pile and throw a lit match on to expecting a fire.

I will concede that the Korolev ice mass is actually larger than what we might want to start with.  However the crater has a "Cold Trap" that very likely would tend to hold any water in that we caused to evaporate.  It would likely tolerate a degree
of human manipulation of some parts of it.  However to melt the whole thing would be insane.

However you should remember that I did see Robert Zubrin, suggest colonization of it with Nuclear power.  I feel that I may have "invented?" some methods to use solar energy as well, and also to conduct sunlight filtered of much of the toxic parts, to grow crops.

You yourself suggested putting an aquarium with a glass bottom over a habitat.
Robert Zubrin suggested the same thing.

Now I understand that the first habitation of Mars will not be there or by those methods, but ASAP, then these new things could be tried.

I am very sad that on this site, innovation is stifled all the time and circling back to old things are promoted all the time.

I would like you to discuss the innovations I suggested, not just dump a stifle on things I present. 

Your blanket response to end all discussion is not appropriate.

I really needed to tell you that I think your methods are wrong.

Done.

Last edited by Void (2021-09-10 19:25:35)


Done.

Offline

#482 2021-09-10 20:31:25

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

Think about the duel purpose of an aquarium to allow natural light into a habitat space that is filtered for the potential radiation that men are sensitive too. Its by and far less water to gather for a multi use purpose for fish to thrive in for food and for algae to grow in plus many more things that we use water for. The system is a sealed to mars atmospheric conditions and is used to hold excess oxygen, filter co2 if salt water ect...the only issue is the manufacturing of the fish tank its self, until we have the source of insitu materials and energy and sufficient water to fill it with.

As far as the crater we have not any boots on the ground testing of the water content that is believed to be there. Not to mention that nuclear is the only way a man can survive as its so close to the pole cap.
720px-Mars_G%C3%A9olocalisation.jpg

dot for marking location does not show
https://geohack.toolforge.org/geohack.p … e:landmark

instrument used is in orbit
https://en.wikipedia.org/wiki/SHARAD

https://mars.nasa.gov/mro/mission/instruments/sharad/

looks at the amount of reflected signal to make a calculated number

SHARAD (Shallow Radar) looks for liquid or frozen water in the first few hundreds of feet (up to 1 kilometer) of Mars' crust
current Nasa rovers have measured very little water content so the need to do more is a requirement to go to mars.

Offline

#483 2021-09-10 20:40:00

Void
Member
Registered: 2011-12-29
Posts: 6,975

Re: Air. Shelter. Water. Food.

The nature of the water content anywhere on Mars, is subject to the unknown at this point.  I feel that there will be lots of not good things in the ice.  Still that can be handled.

What if humans never left Africa for Eurasia, because it was "Too Cold"?

We are called to adapt, and also to adapt the environment around us.  That is how humans inhabited Eurasia.

Now, the polar areas on average get not that much less sunlight than the equator of Mars.  But the lighted season has a very dense reception of photons, compared to the darker season.

The Inuit adapted to our north polar area, but they likely could not survive in Antarctica without modern technology. Same as the rest of us.

Yes Nuclear for Korolev.  And eventually, on to the poles themselves.  That is where the biggest jewels of water are.

But you have only allowed for an aquarium covered habitat, and I am grateful for that much progress.

However, I have suggested a whole set of innovations which involve solar as well as nuclear, and you seem totally not willing to even admit that that exists.  If I post, my expectations are that someone replying will address what I posted.

As for Korolev being near the North Pole of Mars. I have already indicated that much heat and food, can be stored in ice covered bodies of water created by nuclear and solar.

I also note your resistance to Heliostat methods, but still I am sure you would that the SpaceX robot will be OK when it is provided as real.

Yet Heliostats are much more simple examples of Robots.  They redirect Photons for a purpose.

And if you were responding to the materials I provided, you would note that my preference is that most humans do not stay the winters in the high northern latitudes, but to migrate so as to be in the sunny seasons almost all of the time.

I am thinking 4 dimensionally.  I do not just focus on the start.

I want to project a rational estimation of what the future may possibly hold, so that the start and continuation can become less wasteful, as to have taken the wrong path and been blocked in the wrong branch of a network of possibilities.

Still will you consider looking at the solar technology I am suggesting?

The thing is that is the bulk of what I was aiming for.

Why are you so adverse to robotic Heliostats?

I am going traveling tomorrow and for a few days.  I may not respond in a timely fashion.


Done.

Last edited by Void (2021-09-10 20:53:25)


Done.

Offline

#484 2021-09-11 12:39:19

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

6 months out of the year no light means you are using lanterns which in that period of developing community happened to be whale and other oils. Furs were collected and made use of ect.. this will change for mars as the night is 1 year plus long and there is no backup fuel or furs to make use of.

A  Heliostat can work for just half a mars year but even that needs a means to drain all of the molten salt from the tower as its going to freeze solid and distroy the tubing that would be made use of. The size of the reflecting surface will be larger not only to compensate for the northern lower level of isolation from the angle of the light getting to mars but as well as to provide the energy that we need due to efficencies of such a system.

That means we need KRUSTY nuclear units to even allow man to survive for heat and power as thats as heavy as we can lift currently until a landing has been made with the starship on the mars surface.

Next under the same mass issue is just landing enough to support manned missions at such a location and until we can land greater mass than a rover we are stuck dreaming.

Offline

#485 2021-09-11 20:18:08

Void
Member
Registered: 2011-12-29
Posts: 6,975

Re: Air. Shelter. Water. Food.

Well, you are a glass half empty sort it seems.

So what then.

It amazes me to what extent I go to explain something new, and then to discover, that others have no idea of what I intend.

See my posts #474 & #475, if you wish, maybe that will help.

See about "Sydney Receivers".  Basically a 90 degree elbow with a mirrored surface
inside.  My intention is to send light directly into a growth chamber from Heliostats.

No tower, no molten salts.  Sort of a "Light Pipe".

I have also been trying to mitigate harsh radiation and GCR problems.  I am pretty confident that that will work out.

In the "Sydney Receiver", the light would be bent from ~+/-? degrees to more or less down, down through ice and into water.  If you need to understand that better then ask for more info.

Now in my traveling today, I realized something.  That often happens when I travel.   Stimulation and sunlight perhaps.  I realized that the ~90 degree light pipe, could go sideways.  The light coming from Heliostats in the north, entering
the 90 degree pipe, and then going either East or West, into a growth chamber.
In this case however, there could be issues of heat.  You would need glaze wall, probably on the East or West portion of the pipe.  It would have to be able to put
up with some heat.

If you like, imagine a spiraled snail shell set on its side.  Have a mirrored surface on the interior walls.

Now, I bet you are going to say "Not Efficient".  Well, yes each reflection will be only a certain part efficient to the next one.  However, if you pump enough light into the mouth of this device, then it is possible that enough will reach the growth
chamber, to suit your needs.  The mirrored surfaces very likely will heat up.  But so what, put heat exchanger pipes into the walls, and then you not only have a spiral light pipe but a boiler/heater.

So then, in this case, you can heap regolith over the snail spiral, except for the entrance of the shell.  That entrance will point north, if you are in the northern hemisphere.

Now you have separated toxic radiations from visible light to project into your growth chamber.  Next then by various means you might reduce the amount of U.V. light.  This could be heliostats that do not reflect U.V. very well, or reflective coating in the spiral light pipe, or some protection for the transparent wall needed to maintain pressure inside above Martian ambient.

-------

It is amusing that although Robert Zubrin, has speculated on habitation of Korolev
Crater, using nuclear fission, melting a lake and having artificial lights, when I add
solar energy, the glass half empty types, decide that it is just not workable, as you won't get nearly as much light in the wintertime as summer.  I am afraid that's funny smile

It was OK, when there was no solar but now since you don't get much solar in the
winter, it is not OK.  That is like someone hating a meal, because suddenly there is a side of peas.

------
And hear is another thing, we can contemplate working with Ceres or Callisto, but the Martian polar caps are too cold smile  Again.

Last edited by Void (2021-09-11 20:43:02)


Done.

Offline

#486 2021-09-11 20:41:49

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

I had to google to figure out what you had been talking about and its just multiple mirrors used to reflect light to a place that its not.

Central Park Sydney

Screen-Shot-2016-03-16-at-4.24.36-PM-1024x676.png

no heliostat in this case its mirrors used on a lower roof top used to redirect sun to an in between building structure for a roof top garden thats at a lower level.
It does look like some sun tunnels or light pipes are being used as well

I have sun tunnels or light pipes on my northern roof to get light into my rooms on that side of the building to reduce energy levels

We are now building underground which is what the hillside project pictures from Robertdyck posts show

Offline

#487 2021-09-11 20:47:51

Void
Member
Registered: 2011-12-29
Posts: 6,975

Re: Air. Shelter. Water. Food.

Thank you sir. (I think).  I appreciate your reply.  I am desperately in need of some sleep so I will end my ranting for now.

I am going to be out of touch at least until Monday.

In the mean time.  The ice slab.  Notice the Crater.

This is approximately at the latitude of Kansas here on Earth.

https://www.space.com/30502-mars-giant- … y-mro.html

I am not sure what the size of this crater is, but it looks interesting.  Perhaps we could "Cut our teeth" on something like that before we progress to more challenging craters or the polar caps.

Nite Nite, not mad.

Done.


Done.

Offline

#488 2021-09-12 11:30:55

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

Natural solar lighting suffers from the source levels of just 430 w ^m2, yearly dust storms of varying intensity to near total opacity, seasonal duration for mars which like on earth year you would need to compensate twice as long for.

https://aip.scitation.org/doi/pdf/10.1063/1.5117574
In-situ reflectivity monitoring of heliostats using calibration cameras

https://core.ac.uk/download/pdf/188220743.pdf
Optical performance of the reflective surface profile of a heliostat

https://www.sciencedirect.com/topics/ea … heliostats
Solar Thermal Systems: Components and Applications

http://www.redrok.com/concept.htm
contains Absorptivity & Emissivity table and reflectivity as well

So the fact that we want natural light means that we are reflecting unfocused beams into a room glass window or other light pipe media for bringing in the light to a room with a diffuser lens used to spread the light out.
Of course since the reflective surface is outside its going to need to be cleaned often.

Offline

#489 2021-09-12 11:43:46

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Air. Shelter. Water. Food.

For SpaceNut re #488

Thanks for all the links about heliostats ...

SearchTerm:heliostat see post #488 for links

I was intrigued by your closing paragraph:

So the fact that we want natural light means that we are reflecting unfocused beams into a room glass window or other light pipe media for bringing in the light to a room with a diffuser lens used to spread the light out.
Of course since the reflective surface is outside its going to need to be cleaned often.

The reflective surfaces don't need to be outside.  They can be ** inside ** purpose-build dust shelters with transparent film that can be rotated slowly throughout the Sol, so that the dirty surface goes under the structure for cleaning, and the newly cleaned surface comes out the top.

A positive air pressure inside the shelter would keep dust from seeping inside.

Something like that could be used to protect solar panels as well.

Something like that could be used to protect actual glass windows in habitats.  No need to go outside with a squeegee.

(th)

Offline

#490 2021-09-12 12:35:47

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

Then why bother to make a seperate building just for a reflective surface...just build it over the habitat thats under ground since you are needing to have multiple reflecting surfaces to send th light under ground where we are living. Reflection is equal and oposite perpendicular angles to make it go downward.
mirror55.png

using a parabolic dish and center appex reflection into a light tunnel with difusers at the end before fanning out works for under ground.
9fb6b225c7055498583757f5fa3d8587.gif

Offline

#491 2021-09-12 13:04:17

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Air. Shelter. Water. Food.

For SpaceNut re #490

I admire your enthusiasm!

In Post #488, you observed that if the reflective surface is outside, it will need to be cleaned.

I offered a way to keep such surfaces free of dust, and you appear to have come back with something far more ambitious.

By any chance, is the example you cited from Earth?

Can you adjust the image for Mars? 

My proposal (to protect the surface of the mirror) would not require a full pressure envelope.  All it would require is enough pressure to insure a slight positive pressure inside the volume so dust does not creep inside.  A human habitat dome would require far more strength to withstand the much greater pressure recommended by RobertDyck for habitats on Mars.

On Mars, if you wanted to put your mirrors under a pressure dome, that dome would need to withstand the pressure recommended by RobertDyck for human habitats, while at the same time being transparent to the arriving photons from the Sun, and you would ** still ** have to keep the surface of the dome free of dust.

Your next image will (hopefully) explain how your idea would work!

I'm NOT suggesting your idea wouldn't work! All I'm saying is that ** I ** don't understand it, so (hopefully) another image will make it clear enough so even I can understand it.

(th)

Offline

#492 2021-09-12 15:10:05

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

The first image is the standard how a mirror reflection works for how light bounces off from its surface which then requires more mirrors to correct the beam direction enough to get it down a light pipe tunnel.

The second parabolic dish reflects the beam to the center focal point as does a satelite reciever of which depending on where you set the reflector or thermal reciever you have unfocussed light or concentrated focused thermal energy.

sun-tube-tunnel-explained.jpg

For the light it enters the flexible light pipe tunnel to exit inside of the habitat chamber through a lens to spread the beam out and to allow for a reverse parabolic to further spread the concentrated beam even more so that the light levels being defused is more like what we would desire.

For thermal the light pipe is omitted and you use the focused point to collect the energy with a heat exchanger fluid that is pumped to the under ground for use in a storage tank. The storage can also be a heat exchanger to other working fluids or water depending on need.

Control for the dish is a 2 axis tracking system as it done on earth for satelite reception and how we do it for solar arrays.

The dome chamber can be build to size and made however you would want.

Offline

#493 2021-09-12 16:53:26

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Air. Shelter. Water. Food.

For SpaceNut re collecting solar energy and directing it inside the shelter for human use ...

The topic we ** were ** discussing was (is?) how to keep dust off of a mirror that is ** outside ** the habitat.

Changing the topic to something completely different is like changing a football to a basket ball in the middle of the game.

You started out describing a mirror outside a habitat, and made the reasonable observation that such a mirror would pick up a coating of dust on Mars.

All these other options are distractions from the issue .... if you have a mirror ** outside ** the habitat, how do you want to keep the dust of Mars from obscuring the surface.

Let's try to stay focused.   All these other interesting variations are about something else entirely.

(th)

Offline

#494 2021-09-12 17:18:35

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

With the dish which is a fancy reflective surface, One can place a glass lid over it and no matter if we put it into a glass chamber or a simple cover we are going to need to replace the sand blasted clear glass after a period of time. So less energy for a lid version or a large energy expense for a glass house...of course the point is that if you live inside a glass house you might as well see how to stay above ground. Another thing to do for sand blasting of the glass is to give a door cover that can close if its to much such as the cupola onboard the ISS.

Offline

#495 2021-09-12 17:52:05

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Air. Shelter. Water. Food.

For SpaceNut re #494

Thanks for getting  back into the groove where I am ....

OK ... you suggested glass covering for the mirror.  I suggested (may not have said so explicitly) a clear plastic sheet that can roll over rollers so it can be moved over the face of the mirror during the day, so that any dust that collects is removed as the sheet moves below the bottom roller.

A glass covering is definitely a possibility for Mars, but sheets of glass would need to be held in frames.  Glass makers on Mars are going to be limited in the size of the panes they can make for some time.

On the other hand, polyethylene should be achievable on Mars, and rolls can be as wide and as long as needed.

As a reminder, the mirror for a habitat would (probably) be large and flat, and the beam would be projected to flow into the windows of a habitat carved out from under a bluff.  In a recent post, quite possibly one of yours, it was reported that radiation near a bluff is less than in open plain.

Radiation ** inside ** a bluff would be even less.

A flat mirror on the canyon wall opposite a habitat window can beam energy into the habitat by adjusting position all day long, to capture as many photons as possible.

(th)

Offline

#496 2021-09-12 18:45:06

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

clear poly sheets will under mars cold temperatures, will not be rollable and will be brittle after just a few unrollings.

The reflective surface for a mirror here on earth is glass so a frame is required for that type of reflective surface.

2410_12_19-solar-position-with-the-seasons.jpg

A bluff entry means is not going to be easy as that requires an east west alignment and depending on the hemisphere if northern you need to be on the north side to reflect into the glass window on the bluff. As the seasons change the mirrors would need to move back and forth closer and farther away to keep the light going into the window with just a mirror line up still pivoting as the sun rises and sets.

https://www.appropedia.org/Optimizing_r … _latitudes

https://www.freeenergyplanet.biz/free-s … vices.html

Offline

#497 2021-09-12 19:48:53

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Air. Shelter. Water. Food.

OK SpaceNut .... your point about plastic becoming brittle on Mars is a good one and I should have thought of it, but appreciate your reminder.

I ** think ** it was RobertDyck who reported on a transparent form of aluminum.

Aluminum has properties that might allow it to flex at low temperatures, but if it does, it would take research by materials scientists to discover them.

The concern of yours about dust on mirrors mounted outside the habitat is valid and worth pursuing.  However, it is not going to yield to the immediate ideas that have come to mind so far.

You've already pointed out that the mirrors need to be mobile to accommodate the movement of the Sun in the sky, whether by Sol or by Season.

We can extend that idea, just as we've been doing for the lander solar panels.  The mirrors can be designed to rotate so they are face down at night.  While face down, a cleaning robot can blow dust off the mirror (if a supply of clean gas can be obtained).  A mechanical brush would work but (a) it would wear out and (b) I assume the bristles would scratch the face of the mirror.

I'm going to create a search term for this entire sequence .... it is worth being able to find again:

SearchTerm:Mirror how to clean of dust on Mars - note mirror is outside the habitat and subject to coating with dust.

(th)

Offline

#498 2021-09-12 19:52:19

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

transparent aluminum is a ceramic product....
good idea for the double mirror for the panel correction alignment issue...

Offline

#499 2021-09-12 21:20:51

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,749

Re: Air. Shelter. Water. Food.

For SpaceNut re #498

SearchTerm:Ceramic ALON(r) Optical Ceramic Aluminum Ozynitride

Flexible ** and ** transparent are NOT likely to both be present in this material.

RobertDyck has mentioned this material (if memory serves) for spacecraft viewing ports.

Something to think about (in the context of photon routing at Mars) is that mirrors do NOT need to be large single piece devices.

Modern optical telescopes are comprised of many small mirrors that are positioned with great accuracy by individual motion control equipment.  Thus, it can be imagined that an array of mirrors to feed photons into an under-bluff human habitat might be able to steer themselves so that every photon that comes their way during daylight are directed into the habitat, and at night they might all rotate down to undergo cleaning and then stay-clean mode until the next morning.

(th)

Offline

#500 2021-09-13 17:43:50

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,747

Re: Air. Shelter. Water. Food.

The dish units do the same thing in one piece that moves together where as the seperate units need more support to make it work. Working on the glass protector for a dish the cover would rotate and have a wiper combination fox tail, wind fluid dispenser or pressurized co2 misters and a rubber blade to wipe it clean as the cover opens and closes.

Offline

Board footer

Powered by FluxBB