What we need to go to Mars - short term projects

elderflower · 2016-09-28 03:48:44

Strikes me that none of the big agencies have any intention of sending people to Mars then returning them to Earth. If they had they would have an orbital experiment to check the effects of long term exposure to Mars gravity, and to discover whether low gravity diseases can be reversed by gradually spinning up a vehicle over the six month return period. So either they don't intend to go, or they don't intend to bring the people back if they do go.
Also the issue of fuel and/or oxidiser manufacture in situ has been bypassed, and landers are not going to the probably icy areas, where the best resources may be found for this production.
More power to Musk.

GW Johnson · 2016-09-30 11:00:24

Returning to the thread subject: we need a robot drilling rig that can be deployed from a Red Dragon.

It needs to be able to drill at least 10 m down, preferably 100 m down. If I had my druthers, 1+ km down. The objective is to verify or deny whether a "promising" site actually has massive subsurface ice deposits of 10+ meter dimension.

Only that kind of massive deposit can be "fracked" with steam injection for lots of water obtained with very little equipment.

Dispersed small-dimension lenses and veins require strip mining. The equipment to move the volumes, and the facilities to process such large volumes, are large and massive indeed. And for a much smaller yield of water.

Widely available soil moisture is an even less attractive resource: another order of magnitude more massive equipment, another order of magnitude more massive facilities, and another order of magnitude less yield.

Musk says he will send Red Dragons to multiple places on Mars, every 2 years, starting in 2018. He said in Guadalajara that these are to locate the right place to send his big ship. He said in his presentation he needs both Martian air and Martian water to make return propellant for his big ship.

I know of no such robot drilling rig he could use to look for that water. Anybody else know of such?

GW

RobertDyck · 2016-09-30 16:44:07

European Space Agency estimates depth of the frozen pack ice in Elysium Planitia at 65 metres. One of the reasons they haven't been able to confirm presence of ice is their ground penetrating radar can't provide a clear signal from a deposit that shallow. There is the possibility that all ice there has sublimated away. But ESA analyzed craters from meteorite impacts, they believe the craters indicate ice is still there. If they're right, then an average of 65 metres means a drill rig capable of 100 metre depth is sufficient.

SHARAD on NASA's orbiter found ice in the side walls of mid-latitude canyons. Would that require a rig that can drill sideways?

GW Johnson wrote:

I know of no such robot drilling rig he could use to look for that water. Anybody else know of such?

The robot drilling rig called CanaDrill was developed by NORCAT: Northern Centre for Advanced Technology, located in Sudbury, Canada. When the Canadian rover failed to get funding approval from Parliament, they tried to sell their drill to NASA.

GW Johnson · 2016-10-01 09:43:59

"CanaDrill" sounds intriguing. Maybe NORCAT should be talking to Spacex about how to put one on board a Red Dragon. Do you know if it can slant-well drill? They really need that ability to do ice mining. One well with many side legs radially-out through the buried glacier. Much like the way they do "fracking" today.

One well and a steam generator, and you have gobs of water back up the well, already confined inside a pipe. But only from a massive deposit. If thin veins or buried small lenses, they'll have to strip mine instead.

Musk's big vehicle stands about 3-4 times taller than the illustrated spread of its landing legs, based on his presentation slides. That makes it very intolerant of rough ground. The site they pick must be very flat and not cluttered with dunes and boulders.

So, of the possible sites with buried ice, we are interested in the ones with very flat, clean topography. I suspect he will visit these with his Red Dragon missions, whether NASA chooses to hitch a ride with him or not.

He needs to drill robotically from a Red Dragon to find out what kind of ice reserves are there, because that entirely determines what kind of propellant-making and ice-mining equipment he must send with those first several ships.

I would advise caution switching to all carbon-composite construction. It's very intolerant of heat, and it's very intolerant of localized impact damage (such as from thrown rocks or dropped tools). It's also relatively untried as a cryo-tank material. I think they've already run into new-material problems with the aluminum-lithium alloys. All these materials can be really tricky to employ.

GW

SpaceNut · 2016-10-01 19:01:03

Sure drilling rig or even something that can tunnel would be nice but its not just the cost of the ride on the Red Dragon for a mission as there is the developement costs for either option or mining/drilling to which will make the cost go back into a government sponsored mission realm as its not in the interrest of a mission to do science for a private company. All the more power to space x to basically sponsor the first mission to mars with its developing space vehicle in the Red Dragon as then all of the other providers that want contracts will then need to play catch up as they will have already done it in order to show they could do it too.

kbd512 · 2016-10-02 03:48:18

We need an ISRU-only mission to Mars that's purely focused on identifying resource quantities and qualities.

* Atmosphere

How can we filter out the fine particulate matter in the atmosphere to extract CO2 and nitrogen for breathing gases?

* Water

Where are the highest concentration water or brine deposits and what quantities of dissolved minerals and metals are present?

* Metals

What locations have the greatest quantity of ores that can be easily collected from the surface of the planet?

* Concrete

What areas have the highest concentration of sulphur?

Martian concrete will be a bit stronger than Earth concrete, but the process for producing it is highly dependent on sulphur and small aggregate sizes.

GW Johnson · 2016-10-06 14:05:42

Filtering: well established technology, disposable paper filters. Not particularly easy to produce on Mars until there are woody crops, but they are lightweight for relatively low-cost transport there.

Water depends on ice deposits. Are they massive, or are they thin or dispersed? If massive, you can essentially frack them from a well with a steam generator. If not, you must strip mine, process enormous volumes, and accept a low yield. Desalination and de-mineralization we already understand, in multiple forms. Not the least of which is waste heat-powered vacuum flash. Vacuum flash is particularly easy on Mars.

Metals: this needs to be for local production of intermediates and finished products on Mars, for export as higher-dollar items. Ore shipments to Earth is the wrong model for a successful economy in future times. The Spanish made this mistake 500 years ago.

Concrete: I'm not familiar with the sort of sulfur-based material talked about here. Details?

GW

Terraformer · 2016-10-06 14:21:24

I'm been mulling the idea of using a solar sail/mirror for a prospecting mission. Focus sunlight on an area of the planet and see what's in the plume. That could tell us things such as how tightly bound CO2 is in the regolith (for future terraforming) and what form the water is in (if you hit a massive ice deposit, you will know it).

kbd512 · 2016-10-06 15:12:05

GW Johnson wrote:

Concrete: I'm not familiar with the sort of sulfur-based material talked about here. Details?
GW

Materials Scientists Make Martian Concrete

Sulfur concrete as a construction material on Mars

Here are a couple of articles, but Google to your heart's content. There's plenty of information out there.

This is what I want to line the habitat pits on Mars with for a startup Mars colony. SulfaCrete liners, inflatable modules anchored to the bottom of the pits, with some regolith over the top or concrete domes sitting on the concrete liners. Ultimately, we want to construct concrete mining "shacks" that are pressurized to SL using Martian CO2 so workers only need to wear thermal protective clothing and oxygen masks.

elderflower · 2016-10-07 05:47:15

Sulfacrete could be sprayed with suitable chopped fibres and fillers at modest temperature (MP of Sulphur is about 104 C). So an inflatable form can be used and then reused by deflating it and reinflating it on a new ring foundation nearby. Have we found suitable sulphur deposits? I would expect them to occur near fumaroles around volcanic vents.

louis · 2016-10-07 14:03:35

Whilst the original list are are all desirables I think we have to get our prioities sorted. For a 3 person crew the amount of water to be gained from processing faeces could be around 225 kgs on a 100 day flight. How much would the processing equipment weigh? Whatever it weighs is a subtraction from the overall gain. But of course building in processing of faecal matter is bound to carry risks e.g. toxic effects which are v. serious if you are 100 million kms from home.

Personally I wouldn't spend too much time on that. I would pre-land water in the base zone and take on board an extra 200 plus kgs to account for faecal loss.

Urine is less problematical I feel and the calcium issue must be resolved. I'm surprised you can't just boil off urine. Must look into the subject!

We do need to take substantial PV energy generation equipment, although PV panels should have been pre landed to begin processes like rocket fuel production robotically. Batteries should also have been pre-landed along with water, food, and a range of other supplies.

Most importantly, we should pre-land an inflatable habitat

I am with Musk in not seeing the necessity for artificial gravity - simply adds a layer of risk and complexity that can be avoided.

I think the majority of the Mars base equipment should be road tested on the Moon after a 100 day "figure 8" flight between Earth and the Moon.

Whilst an MCP suit would be nice, I think we can skip that if necessary. Stick with the traditional space suit. What would be really useful is to deploy a pressurised rover with digger and other attachments, which could be brought into the habitat. The hab would thus have a large air lock area into which you would drive the All Purpose Rover. The colonists could then simply get into the pressurised Rover in the same way you get into a car in a garage. The vast majority of outdoor activities would thus be undertaken in the Rover.

There should be a farm hab for indoor farming experiments.

RobertDyck · 2016-10-07 18:56:32

louis: I consider the list of the first post to be the short list. Priorities are sorted. You could add all sorts of unnecessary stuff. Robert Zubrin stated in his book "The Case for Mars" (1996 edition) that NASA demands a life support system with 95% recycling efficiency for water and oxygen. I have read the life support system on ISS today has 93% efficiency. The reason for life support improvements is to achieve that 95%, to eliminate a major excuse to not go now. Life support improves are: recovering moisture from feces, recycling wash water, and recovering oxygen from CO2 currently dumped in space. I proposed recovering moisture from feces using the same system that Russia built for the Mir2 core module. That became ISS module Zvezda, but the toilet was completed before the first ISS module Zarya was launched in 1998. And a modification of the toilet known as "Waste Processing/Resource Recovery" developed by the Ames Research Center and tested in the Advanced Life Support System - Phase III at Johnson Space Center in 1997. These aren't new technologies. Direct CO2 electrolysis is based on MIP (Mars ISPP Precursor) on Mars Surveyor 2001 Lander. Unfortunately that lander was cancelled after failure of Mars Polar Lander. The vehicle was converted into Mars Pheonix, the MIP experiment was removed. NASA documents state the current water processing assembly on the American side of ISS is already able to process wash water. They only need a way to collect it. The sink and shower is simply the ones intended for the ISS Habitation module, which was cancelled. So there's nothing new here; it's simply a matter of demonstrated an integrated system in space. Using ISS to demonstrate that.

SpaceNut · 2016-10-07 21:15:28

So build the living modules and such to get launched into LEO with all of these things with in it with the capability of artificial gravity only thing remaining is to solve the size of the electrical system which is assumed to be high effiecent solar cell and batteries.

RobertDyck · 2016-10-07 23:15:14

No, we don't need to launch any living modules. ISS already has that. And this isn't to prove electrical systems. This is to prove life support. Once we have life support with the required recycling efficiency, the next step is to operate ISS for the full duration of a Mars mission without cargo resupply.

Mars Direct is 6 month transit to Mars, 500 day surface stay, then 6 month transit back. That adds up to 28.5 month round trip. I have argued for 26 month round trip, so the crew from the first mission is on Earth a couple days before the second crew launches. That means mission control only has to monitor one mission at a time. And the second crew will be assured there is high reliability they will get back alive, because the first crew did. And the first crew can pass on lessons learned. You still want the outbound transit to be a free return, so that limits transit time. Return will be about 180 days. That means reducing surface stay to about 425 days. This may require a little extra propellant, but I think it's worth it. So to use ISS as an analog for Mars, that means no cargo resupply for 28.5 or 26 months, depending which mission profile you want to simulate.

ISS crew does not have to remain on ISS full duration. A real Mars mission will not be in zero-G the whole time. I will argue for artificial gravity for both transits, but even if transits are zero-G, the surface stay will be in Mars gravity. So ISS crew can be changed. However, no cargo resupply because a Mars mission will only have what it takes along, or cargo pre-positioned.

GW Johnson · 2016-10-08 12:02:22

Whether we talk about Musk's gigantic dream, or that big-ship-with-landers orbit-based mission I posted over at "exrocketman", if you have a big vehicle that lands, what do you need a separate hab for? Live in your lander. If you are there to build something permanent, then get on with that.

All you need is a battery-powered front end loader to start construction with regolith, especially if you brought some sulfur to make the Martian equivalent of concrete. You cannot bring stuff like that if you land in small vehicles. That front end loader and the solar or nuclear power to keep it charged is a whale of a lot bigger than the Curiosity rover. Line the thing with a rubber balloon, so the atmosphere doesn't leak out through your porous construction, and, so you don't have to smell that damn stinky sulfur-matrix concrete.

It's actually time to start thinking outside the "min thrown mass" boxes we've all been living in since about 1960. What Musk proposes for Mars actually resembles the big-ship concepts of the 1950's, more than anything I've seen since Gagarin and Shephard. You simply cannot actually build anything substantive on Mars until you start bringing large vehicles. The New World was not explored or colonized from Europe with rowboats. They used what were the full-size ships of that time. There's a real lesson there.

And I do remember stuff like that, before Sputnik. D-558-II, the X-1A/B/etc, and so forth. Up through the X-15. The rocket plane pilots were my heroes when I was single-digit ages. I also remember them cancelling X-20 just as the first 3 were coming off the assembly line.

GW

Last edited by GW Johnson (2016-10-08 12:09:34)

RobertDyck · 2016-10-08 14:03:07

The mission architecture I argued for is a modification of Mars Direct. I would include a lander that's pretty much the same as the Mars Direct habitat. However, include an Interplanetary Transit Vehicle (ITV) aka deep space habitat, which would use aerocapture to go from ISS in Low Earth Orbit to high Mars orbit, and back. It would use an expendable TMI stage, which would be used as a counterweight for artificial gravity, the same as Mars Direct. Instead of an Earth Return Vehicle, I would include a Mars Ascent Vehicle (MAV). The MAV would have a minimum cabin to carry astronauts from Mars surface to the ITV in Mars orbit. The MAV would then act as the TEI stage. Once spent it would be the counterweight for artificial gravity during transit back to Earth. The MAV cabin would have no life support, astronauts would live in their suits until docked to the ITV. In fact, the MAV cabin doesn't even have to be pressurized. The MAV would be pre-positioned on Mars and produce propellant via ISPP just like Mars Direct. This means all propellant for return is produced via ISPP.

When I first came up with this idea in 1999-2000, Russia still had good relations with the West. Robert Zubin suggested using Russia's big rocket called Energia. I learned about Energia in "The Case for Mars". Many Mars Society members gushed about Energia. So my plan shrunk the surface hab to fit on Energia. To compensate, I suggested pre-positioning a laboratory. The lab would be an inflatable, but would not require a micrometeoroid shield like TransHAB or a Bigelow hab. The lab would be folded until on the surface of Mars. Micrometeoroids burn up in Mars atmosphere, they cannot penetrate any deeper than 30km above the Mars surface. They burn up in Earth's atmosphere about 100km up, so they penetrate deeper into Mars atmosphere, but that's still kilometres above the surface. The lab would have an aeroshell that acts as micrometeoroid shield during transit. The inflatable would have the same pressure layers as TransHAB or Bigelow hab, but instead of micrometeoroid layers it would have a scuff layer to protect against astronauts rubbing against it, and more importantly protect from Mars dust/sand storms. For that I recommend a single layer of Tanara fabric. The lab would include a pressurized rover with recycling life support. If the hab fails, the lab would be connected to the rover for life support to act as a backup hab. If everything works correctly, the lab would be moved to the hab so it could be connected. One reason for the lab to be inflatable is to reduce launch mass. Another reason is so it can be moved on the Mars surface. If everything works correctly, lab equipment will be installed in the lab, and air ducts connected to the hab for life support. In the scenario, the hab would have an open rover that astronauts ride in spacesuits. The open rover would look much like the Apollo lunar rover, but sized for all 4 crew.

If we use SLS block 2B instead of Energia, do we need a separate lab? The reason for splitting the hab into hab/lander and laboratory was to fit on Energia, which has a throw capacity about 2/3 that of Ares. And putting the pressurized rover on the lab with only an open rover on the hab was also to fit on Energia. But SLS block 2B will have a throw capacity just a hair greater than Ares. With SLS block 2B we could use a single Mars hab aka lander. Or do we want the separate lab anyway just as a backup? If so we would still want it to be inflatable so it could be moved. Move the tent/inflatable first, set it up, then move equipment to be installed inside.

RobertDyck · 2016-10-08 14:10:53

Concrete: Some members are currently obsessing over sulphur. Portland cement has a little sulphur, but not all concrete blends do. And Mars has sulphur minerals on its surface, so that really isn't an issue.

Wikipedia: Concrete - Mineral admixtures and blended cements

RobertDyck · 2016-10-08 14:17:03

But this thread is about short term projects. The opening post lists stuff we can do right now, most of it on ISS.

louis · 2016-10-08 17:12:35

Sorry I don't agree with your list. I'm not a tetherist for one thing. I think people will be able to cope with a 2 plus years tour to Mars with 80-100 days in zero G. But more to the point - that could be tested by putting people on the moon for a couple of years wearing weighted suits to supplement lunar gravity.

I think when Zubrin wrote his book we weren't clear about how readily available water is on Mars. For me mass preservation on the transit flights is of second order importance really. Musk has already shown that huge amounts of tonnage can be shipped to Mars if we wish.

RobertDyck wrote:

louis: I consider the list of the first post to be the short list. Priorities are sorted. You could add all sorts of unnecessary stuff. Robert Zubrin stated in his book "The Case for Mars" (1996 edition) that NASA demands a life support system with 95% recycling efficiency for water and oxygen. I have read the life support system on ISS today has 93% efficiency. The reason for life support improvements is to achieve that 95%, to eliminate a major excuse to not go now. Life support improves are: recovering moisture from feces, recycling wash water, and recovering oxygen from CO2 currently dumped in space. I proposed recovering moisture from feces using the same system that Russia built for the Mir2 core module. That became ISS module Zvezda, but the toilet was completed before the first ISS module Zarya was launched in 1998. And a modification of the toilet known as "Waste Processing/Resource Recovery" developed by the Ames Research Center and tested in the Advanced Life Support System - Phase III at Johnson Space Center in 1997. These aren't new technologies. Direct CO2 electrolysis is based on MIP (Mars ISPP Precursor) on Mars Surveyor 2001 Lander. Unfortunately that lander was cancelled after failure of Mars Polar Lander. The vehicle was converted into Mars Pheonix, the MIP experiment was removed. NASA documents state the current water processing assembly on the American side of ISS is already able to process wash water. They only need a way to collect it. The sink and shower is simply the ones intended for the ISS Habitation module, which was cancelled. So there's nothing new here; it's simply a matter of demonstrated an integrated system in space. Using ISS to demonstrate that.

SpaceNut · 2016-10-08 19:04:44

As I indicated the ISS can not do the things that we want the living module to do on its way to mars as it can not do artificial gravity, the large solar panels would not supply the power we would require as they would break for sure, the systems keep breaking down long before we make a single round trip time for mars and finally whom is going to pay for the upgrades to get the higher percentage....
If we are going to pay for upgrades let pay for them to be down to what we will fly to mars and not something which could never go.....

These same subsystems would all be used on the surface of mars and more. Insiut elemental use of mars is a must as well. So here is another link to short term efforts https://ninesights.ninesigma.com/web/na … -materials

RobertDyck · 2016-10-08 21:13:40

SpaceNut, louis: I see you two arguing on a fundamental. Artificial Gravity is absolutely critical, because transit won't be 80 days. It'll be a long time before the colonial transport is ready to fly. And it won't be built at all without money. SpaceX has received a lot of support from NASA. They have a paid contract to deliver cargo to ISS. And they have paying customers to launch satellites. That's how they built their rocket. They won't build the colonial transport without money. Who's going to pay for it? NASA won't pay for something that big. And NASA has said they won't pay for any human mission to Mars until life support achieves 95% efficiency. That's what I documented how to do it.

Colonial transport will deliver 100 people at a time. There must be something on Mars to receive them. I've described elsewhere the process I proposed. First robotic demonstration of technology. Robotic analysis of the base site. Then human explorers with a mission based on Mars Direct. Then use Mars Direct to build a larger base using In-Situ resources. Then expand that base. Then use that base to build a larger base able to receive the first 100. Everything before the colonial transport will use 8.5 month transit for robotic missions, cargo, and unmanned landers. Manned missions will be 6 month. That is 180 day transit.

GW Johnson · 2016-10-09 16:27:08

Transit time one-way depends upon how much propellant you expend. I did most of my stuff at Hohmann min energy, which is pretty much 8.5 months one way. It would seem from Zubrin's ideas that 6 months one way does not cost that much more.

6 months, 8.5 months, both seem feasible from a microgravity exposure viewpoint, if one assumes (1) that's the end of the debilitating exposure, and (2) that vigorous exercise of the sort used on ISS is employed while in zero-gee. This is at least adequate for 4 gee exposures measured in a few minutes at the end of that period of time, which seems "realistic" for Mars entry, as well as Earth from LEO.

The problem arises for crew returning to Earth, not crew going to Mars. The worst-case "bail-out" scenario is a free return at around 16 -17 km/s into Earth's atmosphere at a very shallow but very well-controlled path angle. That would seem to fall in the 12-15 entry gee range. Unless you are fully 1-gee "fit", you will not survive this.

It was unclear from Musk's presentation whether his second stage/interplanetary spaceship vehicles were recovered by direct entry landing on Earth, or by entry into LEO for refuelling and reuse there. Direct entry is high-gee, but recovery into LEO can be at or below 4 gee.

It is not clear at all that a year or so on Mars is therapeutic enough to qualify as "1-gee fit", to be followed by a few months home in microgravity. But I'd hazard the guess that with vigorous exercise on the way home, these crew would be no worse off that those returning from ISS after 6 months. 4 gees seems survivable.

That leaves the 12-15 gee bailout as something still likely not survivable, whether Musk's passengers, or ISS crew.

GW

Last edited by GW Johnson (2016-10-09 16:29:18)

Mark Friedenbach · 2016-10-10 03:50:29

There's also the possibility of a cocktail of steroids to be used leading up to and just before Earth re-entry.

GW Johnson · 2016-10-10 16:30:34

Steroids? Are you sure?

I have never heard anything like that proposed.

Actually, if it weren't for the presumably-fragile solar panels, Musk's transport ship is big enough to spin end-over-end for artificial gravity. A 56 m radius at 4 rpm is 1 gee. It's just that out-the-nose is "down", which is inconvenient for most of what else they want to do.

GW

Last edited by GW Johnson (2016-10-10 16:31:46)

Tom Kalbfus · 2016-10-11 22:01:55

direct CO2 electrolysis to recover O2 from CO2 currently dumped in space
This won't replace the current life support system, it will augment it. Currently 50% of CO2 recovered from cabin air is dumped in space. The other 50% goes to the Sabatier reactor. Direct CO2 electrolysis only recovers 40% of O2 contained in the CO2, but 40% is better than 0%. This could replenish recycling losses.

Why can't you recover all of the oxygen? If you heat it to a high enough temperature, you can break any chemical bond and recover all of the oxygen!

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