Where would you put your Mars base?

[anonymous]

I think that Robotbeat kid likes Hellas Basin because of the somewhat higher pressure and benign thermal environment where at certain times of the day liquid water might actually be thermodynamically stable!

I always liked Hellas for the same reasons. Didn't know about the dust storm issues. I guess that makes sense; denser atmosphere can pick up more dust particles.

But is there any water in Hellas Basin? Maybe it's the Death Valley of Mars....

A large part of the reason I like it is that it is the easiest spot on Mars for atmospheric entry. Thus, for the same sized heatshield and same sized parachutes, you can land a lot more cargo.

I realize it might not win on all aspects and whenever a Mars base or something is developed (I'm not sure what century that will be, it'd be nice if it were this one), a different spot may be picked. But it does have several unique aspects to it that make it pretty attractive as a base. I believe it does have buried glaciers, according to radar soundings.

The higher air pressure has many positive aspects... It makes utilizing the Martian atmosphere for ISRU easier, it makes nuclear fission reactors and radioisotope generators more effective because of the more efficient thermal transfer, it adds another little bit to the factor of safety of any pressure vessels, it allows a little more grace in case of leaks, it might make wind power more viable (Mars has generally more predictable weather than Earth... complex weather systems repeat themselves every Martian year or so), it attenuates space radiation, and reduces harmful hard UV rays (thus allowing more flexibility in materials that can be used on the surface).

If someone has quantitative data showing the frequency of dust storms in Hellas Basin versus other areas, I'd be interested. I highly doubt we'll build on Olympus Mons, though (even though dust storms don't affect it so much because of its high altitude).

I found Robotbeat's arguments intriguing and it made me think about where would be a good place for a Mars base, so I've started a thread about it. I found the arguments for low elevation because of being able to land more cargo and for attenuation of radiation the most convincing, but the argument for Hellas Basin itself less convincing.

It seems to me that the problem with Hellas is that apart from its low altitude it's not a very convenient location. It's an impact basin about 45 degrees south, surrounded by the southern highlands. It's a long way from many of the most interesting parts of Mars, which are in the northern hemisphere or near the equator. The Tharsis volcanoes are on almost the opposite side of the planet from Hellas.

I looked at topographic maps of Mars, this being perhaps the most informative:

http://mola.gsfc.nasa.gov/images/topo_labeled.jpg

The northern plains strike me as a better location because they are more interesting in themselves (now believed to be dried-up sea beds) and closer to other sites of interest. Utopia Planitia and Acidalia Planitia (north of Chryse Planitia on the map) are not much less depressed than Hellas and, as befits dried-up sea beds, also probably have subterranean ice deposits.

Dust storms are a consideration, but they emanate from the southern hemisphere and the northern hemisphere is less affected. Maybe it would be better to choose a site with higher elevation, but I would like to see more evidence about the frequency of dust storms in support of that argument.

[A_M_Swallow]

The base does not have to be near the landing site.  A rover could carry cargo for a couple weeks to the base.  However passengers may prefer a shorter trip.

[Dalhousie]

The base does not have to be near the landing site.  A rover could carry cargo for a couple weeks to the base.  However passengers may prefer a shorter trip.

ON Earth remote area locations have an airstrip within a few minutes drive at most an hour.  I don't see why Mars would be that much different.

[A_M_Swallow]

The base does not have to be near the landing site.  A rover could carry cargo for a couple weeks to the base.  However passengers may prefer a shorter trip.

ON Earth remote area locations have an airstrip within a few minutes drive at most an hour.  I don't see why Mars would be that much different.

On Earth high locations can be inaccessible by helicopter.  Problems with vertical landings on Mars are worse.

[Dalhousie]

This is a good question.  I am assuming "base" means and established long term station, not initial missions.

Engineering constraints first. 

It has to be flat over a 10 km radius. Equitorial for launch and landing. Within 25 degrees N and 15 degress S for solar power .  Below 0 datum elevation for air density.  The surface has to be firm, for easy going, and easily excavated. 

Second, resources.

At this stage water is the most important.  The low latitude constraint probably rules out ice (but we might be lucky).  That leaves hydrated minerals, especially sulphates, alternatively clays.

Third, science.

The science objectives for Mars are currently astrobiology, history of the surface environment and atmosphere, and human habitabilty.  We can assume that the last would be met by the station regardless of where it is established.  For the first to we would want a region that has as diverse a range of features (good stratigraphic exposures, areas of active slope processes, both water and non-water related, areas with high habitability indices) and ages (Noachian to Amazonian as possible, probably within a 1000 km radius.

So Meridiani, Gale, parts of Vallis Marineris (assuming they are flat enough), and Nili Planum would fit the bill.

Long range surface mobility, 100s of km certainly 1000s if possible, is very important for scientific exploration.

[Dalhousie]

On Earth high locations can be inaccessible by helicopter.  Problems with vertical landings on Mars are worse.

You would not want to put your station in a place that was inaccessible.  With a few exceptions, first remote facilities on Earth are sited where they are accessible.

On Mars the distance from your launch and landing site would, I suspect be as close as safety issues allow.

[go4mars]

Depends entirely on what sort of geological feature iwas studying.

[Dalhousie]

Depends entirely on what sort of geological feature iwas studying.

A Mars station would not just study one feature.  Take polar stations as an example, they provide central hubs for multi-discplinary research across large areas.

[go4mars]

Hellas.  Easier to store water and fluids.  Could drop a deep mine-shaft at the bottom of Hellas until you are down in warm rocks.  At that depth the pressure would be much greater yet.

The big downside is that an infrastructure build-up in Hellas would make really long term plans for terraforming more controversial. Lake Hellas would displace everyone. 

[jimvela]

Me, I'd find one of those lava-tube sink holes that HiRise has found, and put my first base inside there.

Ultimate goal being to seal it up, pressurize and create a shirtsleeve environment inside.

Note:  Precursor robotic surveyor sent first, to pre-position supplies and check out the tube for anything unfavorable before sending the first robotic construction mission.

Why not take advantage of billions of dollars of excavation that nature itself has seen fit to provide for us?

[the_roche_lobe]

Most of those sink holes are high up on the Tharsis volcanoes - kms above datum. So you have a real EDL problem there.

P

[anonymous]

I was thinking about it some more and I realised that planetary protection means you would want to put your base in an area that doesn't have any subterranean ice until you were certain that there isn't still any Martian life. Actually, I don't think humans should land anywhere on Mars until it's almost certain there isn't any Martian life, although I know that a species as short-sighted as this one won't be that prudent.

This is a good question.  I am assuming "base" means and established long term station, not initial missions.

Engineering constraints first. 

It has to be flat over a 10 km radius. Equitorial for launch and landing. Within 25 degrees N and 15 degress S for solar power .  Below 0 datum elevation for air density.  The surface has to be firm, for easy going, and easily excavated. 

Your point about a equatorial location for launch and landing is a very good one that I had overlooked. It's probably more important than getting the lowest altitude.

Second, resources.

At this stage water is the most important.  The low latitude constraint probably rules out ice (but we might be lucky).  That leaves hydrated minerals, especially sulphates, alternatively clays.

There may be quite a lot of ice even at low latitudes:

http://www.universetoday.com/93059/large-amounts-of-water-ice-found-underground-on-mars/

...which is a problem for planetary protection because there is bound to be contamination from a base.

Third, science.

The science objectives for Mars are currently astrobiology, history of the surface environment and atmosphere, and human habitabilty.  We can assume that the last would be met by the station regardless of where it is established.  For the first to we would want a region that has as diverse a range of features (good stratigraphic exposures, areas of active slope processes, both water and non-water related, areas with high habitability indices) and ages (Noachian to Amazonian as possible, probably within a 1000 km radius.

So Meridiani, Gale, parts of Vallis Marineris (assuming they are flat enough), and Nili Planum would fit the bill.

Long range surface mobility, 100s of km certainly 1000s if possible, is very important for scientific exploration.

Meridiani would meet your criteria. Vallis Marineris would be great if there are parts that are flat enough, but I doubt it. I don't think it would be easy to drive out of Gale. Nili Fossae is too high and rather rough; Isidis Planitia, just to the east, seems better.

The eastern part of Meridiani also seems to have little sub-surface ice, but we know it's full of hydrated minerals.

Further west, Chryse Planitia is lower-lying than Meridiani and also seems to have little sub-surface ice. To the east, Isidis Planitia is also low-lying and seems to have little ice. I don't know how they are for hydrated minerals. Both these areas are part of the former Martian ocean.

Chryse has river beds and Valles Marineris to the south and Tharsis to the west. Isidis is next to Syrtis Major and Nili Fossae, with Elysium to the east.

[anonymous]

I think that landing humans on Mars would be folly before robotic exploration had shown pretty conclusively that no life was present. I tend to assume that there isn't any life on Mars, that it's just a case of hope springing eternal in the human breast, but of course I don't know that. It would be awful if astronauts going to look for them caused the extinction of Martian life forms. If recent results indicating ice underground everywhere are correct then contamination would be practically inevitable. If there are areas shown to be completely ice-free then the risk of contamination would be less, but I doubt it would be worth taking even that risk because the consequences would be irrevocable and render the entire exercise totally counter-productive. Our history of wiping out the native fauna and flora on this planet should not be repeated on another one.

[go4mars]

Name one endolithic organism that humans have made extinct.  Not sure it would even be possible if we tried to.

[anonymous]

I don't think we have known about endolithic organisms for long enough to know if we have introduced ones from one part of the world to another. We do know we have (sometimes deliberately, sometimes inadvertently) introduced animals and plants from one continent to another continent or to islands, where the introduced species has out-competed the native species or played havoc other ways. In this case it would probably be about inadvertently introducing terrestrial endoliths that out-compete or poison Martian endoliths.

[Warren Platts]

Robots simply may not be up to the task of finding life on Mars; probably if it exists it won't be endolithic life on the surface; the UV radiation and perchlorates could prove to be too much. However, if there are liquid water aquifers these could contain microbial, and perhaps even multicellular life. To get at that would require drilling down perhaps thousands of feet. Contamination is certainly a concern; on Earth natural gas wells get contaminated by bacteria that will cause the gas to turn "sour", which is a problem since the H2S has to be removed, but sterilizing the drilling equipment shouldn't prove to be too much of a problem.

[Robotbeat]

This is a good question.  I am assuming "base" means and established long term station, not initial missions.

Engineering constraints first. 

It has to be flat over a 10 km radius. Equitorial for launch and landing. Within 25 degrees N and 15 degress S for solar power .  Below 0 datum elevation for air density. ...

We can get a lot better landing accuracy than just 10km (not just initial missions, remember?). Doesn't have to be equatorial (the advantage isn't THAT great), and the higher air density can literally double or quadruple your payload (for the same sized heatshield and same kind of parachutes, etc), so I think you are underestimating how important it is to have a high air density.

Your low-latitude constraint is being way over-emphasized, IMHO. For a long-term, permanent base, ISRU production may be partly seasonal and there's definitely the option of nuclear surface power (which doesn't care about your latitude BUT heat rejection will work a lot better at higher air density).

[Dalhousie]

I was thinking about it some more and I realised that planetary protection means you would want to put your base in an area that doesn't have any subterranean ice until you were certain that there isn't still any Martian life. Actually, I don't think humans should land anywhere on Mars until it's almost certain there isn't any Martian life, although I know that a species as short-sighted as this one won't be that prudent.

The primary science objective of the Red Dragon mission concept is to test whether or not there is extant life.

There may be quite a lot of ice even at low latitudes:

http://www.universetoday.com/93059/large-amounts-of-water-ice-found-underground-on-mars/

Like I said, we could get lucky.

...which is a problem for planetary protection because there is bound to be contamination from a base.

Only if it has extant life. 

Nili Fossae is too high and rather rough; Isidis Planitia, just to the east, seems better.

Indeed, but the lower slopes of Nili Paterea are much smoother, I was mentally including Isidis in the area, however the surface of Isidis seems to be young lava flows, there may not be a source of hydrated minerals there.

[Dalhousie]

We can get a lot better landing accuracy than just 10km (not just initial missions, remember?). Doesn't have to be equatorial (the advantage isn't THAT great), and the higher air density can literally double or quadruple your payload (for the same sized heatshield and same kind of parachutes, etc), so I think you are underestimating how important it is to have a high air density.

For launch and landing, an equatorial location gives about 10% advantage which is more than on Earth.  Not essential, but useful, I think.

The problem with seeking the areas with the greatest atmospheric density on Mars is that you soon start running out of interesting areas.  If you look at the hyposometric curve, the area below -5 km drops away very rapidly, you want to have options other than Hellas (not that some here would mind)!

I am sure we can get better than 10 km accuracy, we will have to (Apollo did much better than this).  But I wanted there to be a large hinterland.  Interestingly, when discussing this with my pilot friends, they say that much prefer landing in a place that is not completely flat, as it gives them visual references.  This might not be relevant to landing on Mars of course, which may well be fully automated.

Your low-latitude constraint is being way over-emphasized, IMHO. For a long-term, permanent base, ISRU production may be partly seasonal and there's definitely the option of nuclear surface power (which doesn't care about your latitude BUT heat rejection will work a lot better at higher air density).

Why would ISRU production be seasonal?

Nuclear power would certainly increase the latitude range (obviously I was assuming solar power).  With a large enough array you could use solar power outside the 15S to 25N zone as well.

The BIS did a big study of a polar station some years back, which interested people should look up.

[clongton]

My thoughts have always centered around Valles Marineris.
It has several very real advantages:

  1. It's equatorial, offering an advantage to spacecraft leaving the base for orbit.

  2. Low altitude, offering higher air density. The valley is as much as 7 kilometers deep in some places.

  3. Being so deep below the Martian surface, it offers enhanced protection from both meteorites and BCR. Both would need to come in nearly vertically to have an effect on the base.

  4. Being so deep below the surface increases the chances for liquid water to be available.

  5. It's as much as 200 kilometers wide in places, offering lots and lots of low altitude, high air density real estate.

  6. It stretches nearly 1/4 the way around the planet, offering many, many years of exploration and settlement opportunities.

  7. Sheer walls offer the opportunity to expand habitation by drilling, blasting or mining our way into the Martian soil - horizontally (man-made lava tubes).

  8. It would take hundreds of years to properly explore and exploit the location.

  9. Over the years domed facilities could be constructed offering some degree of human normality within facilities naturally protected from the harsher condition above on the surface.

10. It's the ideal location to begin to establish an off-world new home-location for humanity.