Exploring Mars

louis · 2018-06-12 05:02:16

Getting to Mars is one thing. Exploring Mars is another. Exploring Mars will be vital for a number of reasons:

1. Identifying location of water and mineral deposits.

2. Identifying best transport routes for road trails.

3. Scouting potential base or landing areas.

4. Providing a much needed off-base focus of interest for Mars pioneers.

5. Researching the geology, and possible (past or present) biology of Mars.

6. Providing material for TV documentaries, sponsorship deals and so on.

I think exploration will come down the following approaches:

A. Human passenger rocket hoppers. These will be useful in identifying areas of interest but will be limited in how much investigative work can be undertaken.

B. Robot balloons or other aircraft. These could be useful in providing a good understanding of terrain but again will be limited in detailed investigation.

C. Rover expeditions. These will conduct the really important research work.

Focussing on Rover expeditions it's interesting to speculate on how they might be organised.

The rovers would be similar I think to large motor homes, with all those facilities (kitchenette, toilet, shower, beds, entertainment centre etc), plus of course life support and a pressurised environment. There would have to be a number of back up electric battery systems. These would be EV automobiles. They would have their own extendable PV panels (similar to orbital ATK fans) enabling them to offeset discharge of batteries as they move but also larger PV arrays that could be deployed during mid-sol hours to fully recharge batteries. The rovers would be self-drive but have human override as required.

An expedition might comprise say:

3 Rovers - each carrying 2-4 people. A lead rover would be fitted with a deployable cow catcher for boulder/rock removal where possible and appropriate.

Each rover would have a rear integrated double air lock/shower unit to enable EVAs. Crew would wear disposable overalls over their EVA suits so as to minimise dust contamination in the vehicle. EVAs would normally only be undertaken at a target location. EVAs could be undertaken on electric bikes to increase the area of detailed observation. The rovers would also carry mini robot rovers that could be deployed to take samples at any time.

Expeditions would follow established trails leading out of the main base settlement. These would have way stations every 10 kms or so comprising a sizeable PV panel field which would feed large battery stacks (maybe 200 KwHs) that could be used to top up the rover batteries as necessary. The trails would also have water, emergency food and oxygen supplies. The established road trails would be maintained by a team located at the main base settlement.

The rover exploration teams would then leave one of these dedicated trails and head out for their target location. Here progress would be much slower as terrain is likely to be boulder-strewn and the rovers would need to stop mid-sol to fully charge up their batteries (involving automatically unrolling flexible PV panelling located behind the rover. The Rovers would carry robot light aircraft camera drones that could scout the terrain ahead, although the Rovers would be guided by terrain maps based on satellite observations.

Expeditions going deep off road might need to take along a supply rover packed with water, food and other supplies.

A rival to electric rovers might be rovers powered by methane/oxygen but these would be less able to explore independently.

Regarding exploration team selection you would need an expedition leader and deputy, a medic, trained drivers, life support engineer and lead navigator.

Expeditions would lay down markers to help guide later teams and to find their way back easily to the established trails.

Last edited by louis (2018-06-12 07:54:45)

Void · 2018-06-12 11:35:43

Well, I guess that human oriented method would have it's place, but I would really go with drones, as AI will be getting stronger and stronger.

I also see a potential to have a hopper that carries rovers on it.

That is it would hop to a location to investigate, then deploy a significant amount of solar panels, and then send charged up rovers out.

Various sized rovers. Some to investigate rocks on the surface, and some to be so small as to generally drive between stones.

Our "Dear Leader" has this newest thing:
https://www.inquisitr.com/4934964/space … la-to-fly/

So, I am thinking a Tesla Rover with thrusters (Air or combustion) might be quite good on Mars, @ .38 g.

So the "Tesla Rover with thrusters" would be able to jump over obstructions, or push rocks out of the way, or investigate the rocks.

Rocks on the surface should generally follow three categories, if they are on land with significant underlying ice.
1) Meteors. (Least common I would think).
2) From volcano ejections.
3) Impact debris. (I am guessing these being the most common).

So, you would want methods to manipulate and examine the rocks. They after all may be of value in themselves.
#1, could be from ages ago, and might speak about the early solar system in ways that Earth Meteors cannot.
#2, of interest as you could get some idea of what has been going on with volcanism.
#3, of great interest, as you could analyze them for chemical signatures, and if you can guess which impact they came from you may get hints of mineral deposits at those sites.

Of course if you want to prepare a trail by moving rocks aside, that would be part of the action.

The rovers themselves, might have on-board solar panels, but that would just allow them to limp back to the hopper. Ideally the hopper would allow them to do full and quick charges, and perhaps to load up their thrusters.

Radar and solar would be features for examining the sub-surface, particularly if a significant ice layer were present.

The rovers could serve as ears for the sonar. The hopper would be the sounder.

Things you would want to find/build other than trails would be mineral deposits, or evidence of minerals from ejecta rocks. Also you would be looking for new hopper refueling base locations.

Once a drone setup had examined an area, and found it to be of value, then a crewed mission could be mounted to that spot, of the manner you have suggested.

I would think that hopper refueling bases would be crewed at least some of the time.

Done.

Last edited by Void (2018-06-12 11:53:00)

louis · 2018-06-12 16:20:00

Sounds like the Tesla Roadster would need a bit of run up for take-off...that probably precludes it from exploring rocky Mars!

That's said, there is no reason why Rocket Hoppers couldn't operate and carry rovers. However, I feel the more detailed scouting operations would still be better handled by humans.

I think humans either operating in EVA or operating automated smaller rovers from inside the "motor home" could perform the tasks at much greater speed than robots operating by themselves and would better be able to absorb and interpret the billion data points of a rock field. I know that these days that's making a large claim for humans against robots, but that's my judgement, formed in part by seeing just how slowly the existing rovers on Mars operate.

Void wrote:

Well, I guess that human oriented method would have it's place, but I would really go with drones, as AI will be getting stronger and stronger.
I also see a potential to have a hopper that carries rovers on it.
That is it would hop to a location to investigate, then deploy a significant amount of solar panels, and then send charged up rovers out.
Various sized rovers. Some to investigate rocks on the surface, and some to be so small as to generally drive between stones.
Our "Dear Leader" has this newest thing:
https://www.inquisitr.com/4934964/space … la-to-fly/
So, I am thinking a Tesla Rover with thrusters (Air or combustion) might be quite good on Mars, @ .38 g.
So the "Tesla Rover with thrusters" would be able to jump over obstructions, or push rocks out of the way, or investigate the rocks.
Rocks on the surface should generally follow three categories, if they are on land with significant underlying ice.
1) Meteors. (Least common I would think).
2) From volcano ejections.
3) Impact debris. (I am guessing these being the most common).
So, you would want methods to manipulate and examine the rocks. They after all may be of value in themselves.
#1, could be from ages ago, and might speak about the early solar system in ways that Earth Meteors cannot.
#2, of interest as you could get some idea of what has been going on with volcanism.
#3, of great interest, as you could analyze them for chemical signatures, and if you can guess which impact they came from you may get hints of mineral deposits at those sites.
Of course if you want to prepare a trail by moving rocks aside, that would be part of the action.
The rovers themselves, might have on-board solar panels, but that would just allow them to limp back to the hopper. Ideally the hopper would allow them to do full and quick charges, and perhaps to load up their thrusters.
Radar and solar would be features for examining the sub-surface, particularly if a significant ice layer were present.
The rovers could serve as ears for the sonar. The hopper would be the sounder.
Things you would want to find/build other than trails would be mineral deposits, or evidence of minerals from ejecta rocks. Also you would be looking for new hopper refueling base locations.
Once a drone setup had examined an area, and found it to be of value, then a crewed mission could be mounted to that spot, of the manner you have suggested.
I would think that hopper refueling bases would be crewed at least some of the time.
Done.

SpaceNut · 2018-06-12 17:44:47

We only have so many ways that are possible and none exist to day for man only robotic.

Man could orbit and gaze down at the surface from orbit but he is not.
Man could land someday soon and ATV or RV there way across the planet.
Man could land someday and place down roots to be able to slow drive plus smell the roses.
Man may someday be able to fly around mars but for now thats not happening either.

louis · 2018-06-12 18:07:34

Options are limited. But if Space X can land about 700 tonnes with each cycle, landing some heavy duty rovers (maybe weighing a couple of tonnes each) becomes a definite possibility. By 4 years after first landing you could have maybe 10-15 exploration Rovers in place on Mars. The first task would be to clear some road trails out of the base into promising territory, and establish way stations along the trails.

If you were running several exploration teams out of the base, you'd probably need a dedicated comms team at the base to maintain contact and monitor progress.

SpaceNut wrote:

We only have so many ways that are possible and none exist to day for man only robotic.
Man could orbit and gaze down at the surface from orbit but he is not.
Man could land someday soon and ATV or RV there way across the planet.
Man could land someday and place down roots to be able to slow drive plus smell the roses.
Man may someday be able to fly around mars but for now thats not happening either.

kbd512 · 2018-06-12 19:26:27

Louis,

If SpaceX can send 5 BFS to Mars, 25 tanker flights and 5 cargo ships, I'll dance a jig. Right now, they fly that often in a year. If they can fly that often in a month, then their capabilities are so far beyond anything possible today that there's no functional limit to how much exploration we can do. Every astronaut / cosmonaut / taikonaut on the roster at NASA, ESA, ROSCOSMOS, and any other space agency you care to name off will be on a mission at all times.

If we had ITV's, then SpaceX might only have to fly 5 to 10 times in a month. At 2 flights per week, that's a more realistic launch rate. Can LOX production even keep up with that kind of demand? I know that we have enough LCH4 available that fuel won't limit flight rates, but not so sure about the oxidizer.

SpaceNut · 2018-06-12 20:06:01

If the source of methane is natural as I suppect that we might be able to do, we will be able to power other processes to get oxygen from other sources not the atmosphere as well from that conversion and gathering.

louis · 2018-06-13 09:37:55

I guess we are back to the EROI (energy return on investment). How much of your methane/oxygen generation energy would you have to use to extract, capture and retain methane and oxygen? Obviously the EROI on Mars is going to be less than on Earth, because we don't need to create specific oxygen reserves on Earth when burning methane.

SpaceNut wrote:

If the source of methane is natural as I suppect that we might be able to do, we will be able to power other processes to get oxygen from other sources not the atmosphere as well from that conversion and gathering.

kbd512 · 2018-06-14 04:16:15

SpaceNut and Louis,

Forget about the EROI of LOX/LCH4 production on Mars. The astonishingly low cost and mass of these new long duration space flight proven thin film arrays and robotically fabricated truss structures makes that irrelevant. I'm talking about the facilities required here on Earth just to send a small fleet of BFS to Mars every two years.

Launching spacecraft requires Grade A LOX. To send 5 BFS to Mars per opportunity, the upper stages alone will require 25,800t of LOX. The boosters probably require ~92,000t of LOX. That's about ~117,600t of LOX. That's 3,900t/day. The ASU in Secunda, South Africa, produces 5,000t/day. That kind of LOX plant is a mega scale engineering project.

The Boca Chica site will require its own LOX plant and that plant will have to have unprecedented capacity for space launch. A CH4 pumping station is also required, but obtaining the tonnage of LCH4 required is not a significant problem. This is one of many reasons why the ITV is required. SpaceX needs to send people and cargo to Mars, rather than propellant to LEO.

Even if SpaceX insists on using LOX/LCH4 in their upper stages, the quantities of propellants required for that type of surge capacity is substantial, to say the least.

At this point in time, O2/H2 PEM fuel cells and water electrolysis are far and away more thoroughly proven technology than SOXE/LOX and Sabatier/CH4. It's not an impossible task, but SpaceX can purchase the LOX/LH2 technology today and it's exceptionally well proven.

For reference purposes, some of the liquids required by the STS Program:

A Review of the Supply of Liquid Propellants and Other Fluids in Support of the Space Shuttle Program

GW Johnson · 2018-06-14 09:51:34

From what I read, Musk dreams of sending 2 unmanned BFS's to Mars on the first opposition that they fly there, and 4 the second. One or two of those four are manned. I haven't heard a thing substantive about anything subsequent. That's 6 BFS's to Mars, and 2 to return from Mars. My guess is that he's hoping that effort will bootstrap the desires of the likes of Bezos and Branson to get involved with building a city there.

6 BFS's to LEO total 6600 tons of propellant, 80% of which is LOX. Each of the 6 has to be refilled in LEO, and my reverse-engineering estimates say 6 tankers per BFS to leave LEO. That's some 36 tankers across the two oppositions. That's 39,600 tons of propellant to fly the tankers to LEO, plus another 6600 tons refilled into the 6 BFS's there in LEO.

Total to get that fleet to Mars: 52,800 tons of propellant, 80% of which is LOX. Has to be done over about 2-2.5 years, with the bulk of it the last year, if you are interested in production rates. That's the cost.

The benefit: 6 BFS's on Mars at 150 tons each delivered. That includes "small" crews in two of them. 900 tons less maybe 1-2 dozen folks, call it 700-800 tons of "stuff" delivered to Mars. A lot of that has to be living supplies. A lot more is construction equipment and supplies.

That is NOT a colony, guys! It's not even a respectable base to be permanently occupied. It's a mere start, a temporary tiny outpost. Talking about costs of using this system to start building a colony is still utter nonsense! Angels on the head of a pin.

As I said, Musk's hoping to inspire others to chip in and help build a viable permanently-occupied base. He's hoping the city grows from there. You have to be realistic! Musk is a dreamer, yes, but his dream is realistic, even if over-hyped. Which it is.

As to the return of those 2 crewed BFS's: that's 2200 tons of propellant that must be made on Mars, 80% of which is LOX, which is why massive glacial ice is so critical (cooking tons of regolith for pints of water is just plain nonsense). Can they do that in one opposition? 2 years? I rather doubt it. That first small crew is there for 4-8 years, it would appear.

So, assuming you lose a ship, you're looking at about 60-62,000 tons of propellant over the course of 2-2.5 years to send about a dozen or so people and 700-800 tons of stuff to Mars, hoping they can live long enough to make 2200 tons of propellant in 4+ years in order to come home.

If somebody else chips in and participates, we can start talking about sending rotating crews there to expand that mere outpost into a real base. If nobody bellies up to the bar, it fizzles out and dies.

And by the way, those first shipments of "stuff" will be more about living supplies and propellant plant than anything else. They'll be living in the ships. They're certainly big enough to serve.

A 4+ year campout on a hostile planet living inside the ship that brought you there. Trying to build the means to come home, before the low gravity effects damage your health enough to kill you during entry at Earth. If you fail, you die. Period.

It's going to be a long time yet before anybody will actually want to go there to actually try making a colony. There's a lot of bootstrapping to do. Talking about ticket prices for immigration to Mars is still utter nonsense at this time! Angels on the head of a pin.

GW

Last edited by GW Johnson (2018-06-14 10:02:02)

kbd512 · 2018-06-14 14:03:21

GW,

Everything is "angels on the head of a pin". We could say that about nearly everything we discuss here.

GW Johnson · 2018-06-14 14:27:59

My reverse-engineering estimates of what BFR/BFS can really do are not angels on the head of a pin. They're quite realistic, perhaps slightly on the conservative side. And based on Spacex's own posted data.

The other follow-up estimates I did regarding landing stability and thrown-debris damage risks are a bit more speculative, but still quite realistic. Again, it is based on Spacex's own posted data.

Most speculative is what I found regarding the possibility of providing artificial spin gravity in two BFS's docked tail-to-tail, exactly like they propose for on-orbit refilling. Instead of small-thruster thrusting axially to transfer propellants, I propose small-thruster thrusting 90 degrees away, for spin-up and spin-down.

A set of electrically-driven flywheels and storage batteries, driven by the BFS solar panels, would be less wasteful for spinning-up and spinning-down. The weight of that system does cut into payload, though. I got gees (in all occupiable decks) above 0.5 at 4 to 4.6 rpm. That's just eyeball-scaled from the illustrations they have posted, plus the dimensions they really have posted. Think healthy crew ready for a higher-gee entry coming home at Earth, with lower risk of bouncing off the atmosphere.

Musk's dream really can be made to work. Until we come up with something better that really is ready-to-apply.

GW

Last edited by GW Johnson (2018-06-14 14:29:30)

louis · 2018-06-14 14:40:35

Well the Mayflower carried 180 tons, so I think a mission bringing in let's say 800 tonnes could be said to be establishing a colony. Not an exact comparison, I grant you but interesting nonetheless.

Mission One will include setting up enabling facilities for continued settlement e.g. the propellant plant, the PV power facility and the main hab.

I think you could establish an independent settlement with as little as 2000 tonnes of supplies (with which you could set up a scaled down industrial infrastructure able to produce just about anything you can produce on Earth). I don't think it will be done that way, but by the time you've landed say 10,000 tonnes and have a 1,000 people living there, a Mars settlement will be effectively independent although, for the sake of convenience, maybe 10% of mass used will still be imported.

GW Johnson wrote:

From what I read, Musk dreams of sending 2 unmanned BFS's to Mars on the first opposition that they fly there, and 4 the second. One or two of those four are manned. I haven't heard a thing substantive about anything subsequent. That's 6 BFS's to Mars, and 2 to return from Mars. My guess is that he's hoping that effort will bootstrap the desires of the likes of Bezos and Branson to get involved with building a city there.
6 BFS's to LEO total 6600 tons of propellant, 80% of which is LOX. Each of the 6 has to be refilled in LEO, and my reverse-engineering estimates say 6 tankers per BFS to leave LEO. That's some 36 tankers across the two oppositions. That's 39,600 tons of propellant to fly the tankers to LEO, plus another 6600 tons refilled into the 6 BFS's there in LEO.
Total to get that fleet to Mars: 52,800 tons of propellant, 80% of which is LOX. Has to be done over about 2-2.5 years, with the bulk of it the last year, if you are interested in production rates. That's the cost.
The benefit: 6 BFS's on Mars at 150 tons each delivered. That includes "small" crews in two of them. 900 tons less maybe 1-2 dozen folks, call it 700-800 tons of "stuff" delivered to Mars. A lot of that has to be living supplies. A lot more is construction equipment and supplies.
That is NOT a colony, guys! It's not even a respectable base to be permanently occupied. It's a mere start, a temporary tiny outpost. Talking about costs of using this system to start building a colony is still utter nonsense! Angels on the head of a pin.
As I said, Musk's hoping to inspire others to chip in and help build a viable permanently-occupied base. He's hoping the city grows from there. You have to be realistic! Musk is a dreamer, yes, but his dream is realistic, even if over-hyped. Which it is.
As to the return of those 2 crewed BFS's: that's 2200 tons of propellant that must be made on Mars, 80% of which is LOX, which is why massive glacial ice is so critical (cooking tons of regolith for pints of water is just plain nonsense). Can they do that in one opposition? 2 years? I rather doubt it. That first small crew is there for 4-8 years, it would appear.
So, assuming you lose a ship, you're looking at about 60-62,000 tons of propellant over the course of 2-2.5 years to send about a dozen or so people and 700-800 tons of stuff to Mars, hoping they can live long enough to make 2200 tons of propellant in 4+ years in order to come home.
If somebody else chips in and participates, we can start talking about sending rotating crews there to expand that mere outpost into a real base. If nobody bellies up to the bar, it fizzles out and dies.
And by the way, those first shipments of "stuff" will be more about living supplies and propellant plant than anything else. They'll be living in the ships. They're certainly big enough to serve.
A 4+ year campout on a hostile planet living inside the ship that brought you there. Trying to build the means to come home, before the low gravity effects damage your health enough to kill you during entry at Earth. If you fail, you die. Period.
It's going to be a long time yet before anybody will actually want to go there to actually try making a colony. There's a lot of bootstrapping to do. Talking about ticket prices for immigration to Mars is still utter nonsense at this time! Angels on the head of a pin.
GW

GW Johnson · 2018-06-14 14:51:52

The pilgrims on the Mayflower would have all died the first winter, had it not been for the local Indians.

There are no local Indians on Mars.

Landing 1-2 dozen people and only 700-800 tons of "stuff" is NOT a colony! Not even the start of a colony!

It's not even a real permanently-habitable base. Not until the propellant production plant can produce over 2000 tons in less than 2 years. AND not until at least some of the greenhouse experiments actually work.

Louis, the "colony" comes a very long time after the base actually becomes permanently habitable, and that's with with more food/water/oxygen produced in situ than shipped from Earth. Face reality.

GW

Last edited by GW Johnson (2018-06-14 14:52:51)

louis · 2018-06-14 16:32:51

True but the Mars "pilgrims" will have the benefit (one way or another) of the support of a scientific/technical community of several million on Earth and their scientific forebears, the knowledge drawn from orbiting satellites and the data from the rovers. The Mayflower pilgrims had very limited knowledge of where they were going and what they had to do to survive once they got there. Their support network amounted to a few religiously motivated persons.

Well I'm thinking six people for Mission One. That would be 133 tonnes per person. Probably about the same amount of "stuff" one person on Earth consumes in a lifetime if we exclude food, water and air. It's a significant amount of stuff.

For me a colony is continuity of settlement. We might not get that between Missions One and Two (I am assuming the opposition transfers don't allow for overlap - but I might be wrong) but,thereafter, I think we will (ie I think we will know enough after Mission One to allow someone to live on Mars for 4 years)...but I might be wrong on that.

There have been many colonies on Earth that have been dependent on supplies from the mother country for several years or even permanently. Once again, it's continuity of settlement that makes it a colony, not self-sufficiency.

GW Johnson wrote:

The pilgrims on the Mayflower would have all died the first winter, had it not been for the local Indians.
There are no local Indians on Mars.
Landing 1-2 dozen people and only 700-800 tons of "stuff" is NOT a colony! Not even the start of a colony!
It's not even a real permanently-habitable base. Not until the propellant production plant can produce over 2000 tons in less than 2 years. AND not until at least some of the greenhouse experiments actually work.
Louis, the "colony" comes a very long time after the base actually becomes permanently habitable, and that's with with more food/water/oxygen produced in situ than shipped from Earth. Face reality.
GW

Last edited by louis (2018-06-14 18:22:39)

kbd512 · 2018-06-14 17:15:46

GW,

According to what you said earlier, Earth must supply a tonnage of propellants equivalent to the operating tonnage of an Iowa class battleship just to send 300t to Mars. Maybe I'm the only one, but I'd be looking for a much more efficient way to do this or it's unsustainable and thus no colony will be able to mature into a self-sustaining operation. Then another half century will pass before someone else comes along and makes an attempt at real progress. Failure is always an option, as all of human history has demonstrated. I don't want this venture to fail.

louis · 2018-06-14 17:29:35

Kbd, I think there are some assumptions in your post. The amount of tonnage you need to send to Mars reduces proportionally as the ISRU industrial infrastructure on Mars expands. Even if nothing changed in terms of rocket technology, the Mars colony itself could afford to pay for transport from Earth to Mars and back. If necessary it could build the rockets, and manufacture the propellant. There is hardly anything in a rocket that can't be produced on Mars as far as I know. Maybe 30% of a community of 10,000 on Mars would be involved in rocket and propellant production...but it would be worth it to have that lifeline back to Earth bringing more and more people to Mars every year.

kbd512 wrote:

GW,
According to what you said earlier, Earth must supply a tonnage of propellants equivalent to the operating tonnage of an Iowa class battleship just to send 300t to Mars. Maybe I'm the only one, but I'd be looking for a much more efficient way to do this or it's unsustainable and thus no colony will be able to mature into a self-sustaining operation. Then another half century will pass before someone else comes along and makes an attempt at real progress. Failure is always an option, as all of human history has demonstrated. I don't want this venture to fail.

kbd512 · 2018-06-14 18:51:38

Louis,

I'm "assuming" that construction efforts to expand will require more delivered tonnage, not less, because that's the way it works here on Earth. There is absolutely nothing on Mars but raw resources and we have limited knowledge of how to exploit those resources in an effective manner because that's never been done before in all of human history. Once we learn how to make steel, aluminum, concrete, glass, and plastics on Mars, then there is sufficient technology for a colony to expand at its own pace. The equipment required to enable production of those materials at sufficient scale to be useful won't simply "happen" after a handful of BFS show up.

The more people you cram into a tiny space, the more outside support they require. All cities and towns on Earth where the populace doesn't merely subsist in Stone Age living conditions is totally dependent upon highly developed and efficient agriculture, energy production, and transportation infrastructures. As of yet, available technology is not Star Trek level stuff. The Mars colony can't contact USS Enterprise over their subspace communications relay to ask Scotty to "beam down" a "food maker" or "matter/anti-matter reactor core".

The Mars colony will never produce anything to economically to ship back to Earth to exchange for more people or cargo with current rocket technology. Advertisements and public donations from well-wishers didn't pay for BFR. Launch of commercial satellites, along with humans and cargo to ISS, and technology investment from the US Air Force did that. SpaceX doesn't have the knowledge, manpower, or resources to start a second branch of human civilization from scratch, tens of millions of miles from home, using rockets with the "F-word" in their names.

It might take a century to put a self-sustaining colony of 10,000 people on Mars with chemical rockets, assuming governments or venture capitalists don't pull the plug first after we find out humans don't do well in .38g or this entire idea turns out to be far more expensive than anyone ever imagined.

The bottom line is that chemical propulsion efficiency is horrid at best and we already have much better technology operating in space as I write this, and have had for many years now. It's time to take the next logical step and apply the things we have to solve the problems we need to overcome to do the things we say we want to do.

SpaceNut · 2018-06-14 19:23:35

Louis wrote:

Once again, it's continuity of settlement that makes it a colony, not self-sufficiency.

That would make the ISS a colony....

Any BFR landings that require men to setup anything on the surface of mars is not a starter colony as its just stuff to unpack once you get there...I do agree that pemanent presence is a requirement to call it any other word not a sortie mission. So the first few are even thou there are such a long duration are just setting up a settlement for what will be a colony as we are going home after each. Maybe a skeletal crew would be permanent for more than 1 to the 3rd mission before going but its only after proving the health of men returning with gravity.

Tonnage landed on mars needs a manafest to show what we can do with what is packed and the alloted time for getting unpacked as well as timeframe to show what can be accomplished with that cargo.

Think building or expanding existing highways for what cargo and timeframe for completion of the task of building with the crew size we go with.

louis · 2018-06-14 19:39:11

kbd512 wrote:

Louis,
I'm "assuming" that construction efforts to expand will require more delivered tonnage, not less, because that's the way it works here on Earth.

Last time I looked, just about everything we used on Earth apart from insolation came from Earth. Why shouldn't the same apply on Mars? Mars won't require anything (at least, as a matter of necessity) from Earth once it has its own industrial infrastructure.

kbd512 wrote:

There is absolutely nothing on Mars but raw resources and we have limited knowledge of how to exploit those resources in an effective manner because that's never been done before in all of human history. Once we learn how to make steel, aluminum, concrete, glass, and plastics on Mars, then there is sufficient technology for a colony to expand at its own pace. The equipment required to enable production of those materials at sufficient scale to be useful won't simply "happen" after a handful of BFS show up.

Well that's where we differ of course as I think it will indeed happen after a few BFS show up, my reasoning being that those few BFS will have some very well focussed contents e.g. automated PV panel production machinery that will allow Mars to create its own PV panels and thus secure energy independence immediately...and then other automated machines that will allow Mars settlers to manufacture machines that can make machines that make PV panels. At that point Mars will become energy independent for all time.

I think you aren't really getting your head around this small scale industrial infrastructure (SSII). On Earth there is really no incentive at all to create any SSIIs even though they are technically feasible. That's because it's nearly always cheaper and more efficient to fly in supplies than create a wide ranging SSII. But the economics of Mars are completely different. It's extremely costly to get stuff from Earth to Mars...but being on Mars produces lots of revenue streams...and it's quite cheap to set up an SSII on Mars (certainly no taxes, no licensing, no rent, no labour laws, no need to defend against Earth-like extreme weather events, no on costs like that).

kbd512 wrote:

The more people you cram into a tiny space, the more outside support they require. All cities and towns on Earth where the populace doesn't merely subsist in Stone Age living conditions is totally dependent upon highly developed and efficient agriculture, energy production, and transportation infrastructures. As of yet, available technology is not Star Trek level stuff. The Mars colony can't contact USS Enterprise over their subspace communications relay to ask Scotty to "beam down" a "food maker" or "matter/anti-matter reactor core".

There is nothing sci-fi about Mars colonisation technology. It's all well established, though it might need a bit of working in over a couple of decades. All you need to make a success of living on Mars in terms of material input is an energy system that will create a signifcant energy surplus. For a community of 1000 people on Mars, that might mean putting in place an energy system that on Earth in advanced industrial societies might serve 10,000 people. That's all it takes - enough energy to keep 10,000 people alive on Earth. 10,000 out of 7 billion. It's a blink of an eye in terms of the Earth's economy. Musk, Bezos, Gates...they could all fund that individually.

kbd512 wrote:

The Mars colony will never produce anything to economically to ship back to Earth to exchange for more people or cargo with current rocket technology. Advertisements and public donations from well-wishers didn't pay for BFR. Launch of commercial satellites, along with humans and cargo to ISS, and technology investment from the US Air Force did that. SpaceX doesn't have the knowledge, manpower, or resources to start a second branch of human civilization from scratch, tens of millions of miles from home, using rockets with the "F-word" in their names.

Take a look at the Rolex Watch market, particularly the luxury end of the market. See how much these v. lightweight objects are selling for. Then compare with likely Space X transfer costs. Then think about the marketing potential of a watch assembled on Mars (from imported Earth parts) and incorporating small Mars jewels... If you can't see that would be a huge revenue earner then I don't know how else to convince you. That's just one product I've thought of but there will hundreds I can't imagine but entrepreneurs will.

kbd512 wrote:

It might take a century to put a self-sustaining colony of 10,000 people on Mars with chemical rockets, assuming governments or venture capitalists don't pull the plug first after we find out humans don't do well in .38g or this entire idea turns out to be far more expensive than anyone ever imagined.
The bottom line is that chemical propulsion efficiency is horrid at best and we already have much better technology operating in space as I write this, and have had for many years now. It's time to take the next logical step and apply the things we have to solve the problems we need to overcome to do the things we say we want to do.

I've nothing against better means of propulsion to improve transport between Earth and Mars but it is simply ludicrous to think that settling a planet with the same surface land area as Earth, near enough, and access to a huge range of minerals (virtually the same as Earth) could be anything other than incredibly profitable. There were plenty of English folk back in the early 1800s who thought it was mad to settle Australia with its deserts and its generally inhospitable character. My view is that iron is iron, water is water, basalt is basalt, silica is silica...whether it's on Earth or Mars. We are talking about a few thousand people being given access to a range of resources currently used (on Earth) by 7 billion people. It's going to be an incredibly successful enterprise!

SpaceNut · 2018-06-14 20:47:55

Earth to mars comparisons; when what we are starting with for mars is zero and earth has about 600 w more per meter more than what mars even if earth was the same as mars no air no water to speak of and no food.

So if we ship all that we need to cover for the energy, water, food and air what is there left even if there is just 1 person for what would be a complete mission duration when nothing is setup or running?

I have not seen any cranes yet that can put the load onto the hook and lower it all by automated means followed by disconnect of the load and have it move away from the drop zone? Sure a electro magnetic coupling to an assist frame makes the means for the cargo to be lifted by that means and would reduce each drop or lift of that cargo to the surface with still no means to move it out of the way for the next.

kbd512 · 2018-06-15 01:17:01

Louis,

Point #1:
Mars is starting from scratch. There's nothing there that's usable without a lot of energy and technology, which will only come from one place.

Point #2:
Constructing a photovoltaic array manufacturing plant on Mars won't do anything for the colonists. It's an utter waste of time and money until the ability to produce air, water, and food exists. The materials fed into that process have to come from somewhere. Here on Earth, the raw materials are mined in one location, transported to chemical plants for transformation into the refined materials required for further use, and then transported again to the company that makes photovoltaic arrays. There are no mines on Mars. There are no chemical plants on Mars. There are no cargo ships, railways, or trucks on Mars, either. Simply being on Mars produces nothing. All the equipment and materials to make photovoltaic arrays must necessarily come from Earth because there is nothing, literally nothing but raw resources, on Mars.

Point #3:

"There is nothing sci-fi about Mars colonisation technology. It's all well established, though it might need a bit of working in over a couple of decades."

If it's well established, then it needs no work. Since it's not well established, it needs lots of work.

"All you need to make a success of living on Mars in terms of material input is an energy system that will create a signifcant energy surplus."

You need a lot more than an energy surplus to "make things work". China has energy, manpower, and manufacturing capacity coming out the wazoo, but they can't make a not-so-simple" jet engine that lasts a third as long as those manufactured by GE, P&W, or RR.

Point #4: Who is going to buy these ultra-expensive Mars-made watches with materials imported from Earth? How many people do you imagine can afford to pay $50K for a watch? My iPhone contains an internal clock that's more accurate than any Rolex watch could ever hope to be and comes with the added benefit of being more useful for hundreds of millions more people than any symbol of social status snobbery will ever become. Gimmicks like that aren't going to pay for Mars colonization, now or ever.

Rolex had a $4.7B total revenue in 2016 and employed 2,800 people to make expensive watches. The company has an average profit margin of 30%, which is three times more than any company I've ever worked for, which would be the people who make the food you eat, the clothes you wear, the medical devices that keep you alive after injury or disease, the vehicles you drive, and the raw materials used for the same. After everyone who can afford a $50K watch has one, then what?

Point #5: It's ludicrous to think that a planet that's not nearly as hospitable to any form of life from Earth as Antarctica is will be profitable without a constant and substantial influx of raw materials, advanced technologies in the form of finished goods, and workers from Earth until infrastructure that's more advanced than anything Earth has is present and self-sustaining on Mars. As hospitable to human life as Antarctica is, by way of comparison, only a handful of people from a planet of 7 billion people live there, and only do so on a temporary basis at that, with copious amounts of government funding and importation of technology and resources. More people have been to Antarctica every summer than have ever been to space. Two dozen men have left Earth in all of human history and half of those actually set foot on the moon.

Water is water if it's not substantially deuterated or tritiated.

We use iron to make steel, but it's not good for much on its own. Any substantial structure built on Earth has thousands of tons of high grade steel in it. The steel was manufactured by burning many more thousands of tons of coal or natural gas. Hundreds of tons of other minerals that were mined were also added to slag off the impurities. That's enough for one building that could hold several thousand people. Surface structures on Mars would have to built like battleships or bunkers to shield the occupants from radiation. If you expend the effort and energy to construct habitable structures on Mars, you want those to last for at least a thousand years.

Here's a study on the theoretical minimum energy inputs required to manufacture steel by the ton:

Theoretical Minimum Energies To Produce Steel for Selected Conditions

2017 World Direct Reduction Statistics

The increasing role of direct reduced iron in global steelmaking

Use of Direct Reduced Iron in Electric Arc Furnace

NITROGEN CONTROL IN ELECTRIC ARC FURNACE STEEL-MAKING BY DIRECT REDUCED IRON FINES INJECTION

We'll need megawatts of continuous electrical power to construct the steel bore hole liners for the subsurface habitats. That means solar power stations that look like the ones in the deserts here on Earth or small fission reactors. That's the kind of power required to mine, refine, and manufacture steel here or on Mars.

This is going to be an incredibly costly and risky enterprise!

Last edited by kbd512 (2018-06-15 01:19:03)

louis · 2018-06-15 04:01:11

kbd512 wrote:

Louis,
Point #1:
Mars is starting from scratch. There's nothing there that's usable without a lot of energy and technology, which will only come from one place.

Agreed that the initial "start up" capital in the form of PV panels, habs, life support systems, batteries, machines, robots, computers and so on has to come from Earth. Space X's BFRs just make it much easier to do so on a significant scale that allows for fast development. If the Mission One approach is maintained then in a decade or so you would land about 4000 tonnes. The other great advantage of the Mars settlement is its low population. On Earth, 7 billion people have to share resources. On Mars for several decades the population will be insignificant. The amount of per capita production and wealth will in Earth terms be stupendous.

kbd512 wrote:

Point #2:
Constructing a photovoltaic array manufacturing plant on Mars won't do anything for the colonists. It's an utter waste of time and money until the ability to produce air, water, and food exists. The materials fed into that process have to come from somewhere. Here on Earth, the raw materials are mined in one location, transported to chemical plants for transformation into the refined materials required for further use, and then transported again to the company that makes photovoltaic arrays. There are no mines on Mars. There are no chemical plants on Mars. There are no cargo ships, railways, or trucks on Mars, either. Simply being on Mars produces nothing. All the equipment and materials to make photovoltaic arrays must necessarily come from Earth because there is nothing, literally nothing but raw resources, on Mars.

I looked into PV panel manufacturing in detailed before. It is now a very highly automated industry and there are plenty of machines you can buy "off the shelf", as it were, which carry out the automated processes of purification, cutting, coating, baking etc. You might initially have to import some specialist chemicals. But they are a small proportion of the mass used which is overwhelmingly silicon, easily obtainable on Mars. Gradually the specialist chemicals from Earth can be replaced by those produced on Mars.

Production of air, water and food is not problematic. We can exclude food for Mission One I think - though there might be a "salad bar" small scale agricultural hab. Producing air is well within our capability, and will in case link in with propellant production.

It's true there are no mines on Mars yet. But, with the exception of water ice mining, you don't need them for Mission One. The other things to bear in my mind are (a) we would be operating in the tens and hundreds, perhaps thousands, of tonnes area on Mars for several decades, not the tens and hundreds of thousands or millions of tonnes required on Earth and (b) the mines do not need to go deep as on Earth, because the minerals on the surface have not yet been exploited. Also, remember that apart from the cold and occasional weak dust storms Mars has very clement weather, so all surface operations are easier from that point of view: no hurricanes, rainstorms, violent tornadoes or major hailstorms and no floods.

When it comes to transport, Mars is blessed by plenty of firm ground over which you can drive rovers. Clear rocks and boulders out of the way and you have a brilliant road network created at virtually zero expense, compared with what is required on Earth. Moreover, because gravity is weaker on Mars it takes less fuel to move goods. Cargo ships are only really a blessing on Earth because we need to move millions of tonnes. We won't need to do that on Mars. Robot rovers can be used to provide continuous supplies of raw materials like silica, basalt, iron ore and so on. Human involvement in the mining and transport but be zilch onsite because it could all be monitored remotely from the base.

Water ice mining will initially be quite challenging. But eventually I am sure water will be piped in through heated conduits from glaciers.

kbd512 wrote:

Point #3:
"There is nothing sci-fi about Mars colonisation technology. It's all well established, though it might need a bit of working in over a couple of decades."
If it's well established, then it needs no work. Since it's not well established, it needs lots of work.
"All you need to make a success of living on Mars in terms of material input is an energy system that will create a signifcant energy surplus."
You need a lot more than an energy surplus to "make things work". China has energy, manpower, and manufacturing capacity coming out the wazoo, but they can't make a not-so-simple" jet engine that lasts a third as long as those manufactured by GE, P&W, or RR.

Space X has access to some of the best engineers on the planet. I think the point about finding successful ways to live on Mars is that you go for simple solutions wherever possible. For instance, when it comes to creating chemical batteries, you won't necessarily look to produce high efficiency lithium ion batteries. You might well choose a less high tech solution using more primitive batteries that are nonetheless highly reliable and do the job. Likewise with construction. Rather than building complex panelled domes, you might choose to use brick and cement and bury your habs in regolith. When it comes to manufacturing vehicles, sticking with electric motors makes sense as they are simple to build.

I think it will be mix and match. But certainly there is no requirement for the early Mars colony to be producing the equivalent of jet aircraft straight off.

Point #4: Who is going to buy these ultra-expensive Mars-made watches with materials imported from Earth? How many people do you imagine can afford to pay $50K for a watch? My iPhone contains an internal clock that's more accurate than any Rolex watch could ever hope to be and comes with the added benefit of being more useful for hundreds of millions more people than any symbol of social status snobbery will ever become. Gimmicks like that aren't going to pay for Mars colonization, now or ever.
Rolex had a $4.7B total revenue in 2016 and employed 2,800 people to make expensive watches. The company has an average profit margin of 30%, which is three times more than any company I've ever worked for, which would be the people who make the food you eat, the clothes you wear, the medical devices that keep you alive after injury or disease, the vehicles you drive, and the raw materials used for the same. After everyone who can afford a $50K watch has one, then what?

The people who will buy Mars Rolex watches are the kind of people who spend $50k or $100k on Rolex watches already. Final assembly with Mars jewellery will just add that extra cachet that justifies another $20,000 on the asking price. A Rolex watch might weigh 100 grams. So you can despatch lets say 9 per kg with packaging. If the cost of transfer from Earth to Mars is say $1000 per kg (Musk is of course aiming lower than that) then the cost per watch for transfer there is $111. OK, double that for the return trip with a few Mars jewels now incorporated at a robot assembly line. That's now $222 per watch out of an asking price of $50,000 plus. There will be other luxury products like that - jewellery, light clothing items and so on. The Mars consortium could negotiate a deal on the watches, with them getting a cut of maybe $20k per watch, a revenue stream of $180,000 per kg. The apportioned costs of precious metal mining, jewellery preparation, and robot assembly would be trivial in my estimation and probably require not much more than a couple of people's oversight.

Point #5: It's ludicrous to think that a planet that's not nearly as hospitable to any form of life from Earth as Antarctica is will be profitable without a constant and substantial influx of raw materials, advanced technologies in the form of finished goods, and workers from Earth until infrastructure that's more advanced than anything Earth has is present and self-sustaining on Mars. As hospitable to human life as Antarctica is, by way of comparison, only a handful of people from a planet of 7 billion people live there, and only do so on a temporary basis at that, with copious amounts of government funding and importation of technology and resources. More people have been to Antarctica every summer than have ever been to space. Two dozen men have left Earth in all of human history and half of those actually set foot on the moon.
Water is water if it's not substantially deuterated or tritiated.
We use iron to make steel, but it's not good for much on its own. Any substantial structure built on Earth has thousands of tons of high grade steel in it. The steel was manufactured by burning many more thousands of tons of coal or natural gas. Hundreds of tons of other minerals that were mined were also added to slag off the impurities. That's enough for one building that could hold several thousand people. Surface structures on Mars would have to built like battleships or bunkers to shield the occupants from radiation. If you expend the effort and energy to construct habitable structures on Mars, you want those to last for at least a thousand years.

I have never accepted that Mars is as inhospitable as Antarctica. On Antarctica resources are mostly buried beneath tons of ice. It has an effective night time that goes on for several months. It has hugely destructive winds. It is very difficult to build on. In Mars all the resources you need are at or near the surface. However, even though Antarctica is a very inhospitable place, temporary whaling communities did live there in the past without a massive government funded infrastructure. If you set aside the Antarctic treaty there are places on the continent where you could with sufficient investment set up a thriving community growing food under glass cover using modern technology and local resources.

I have not argued that you can establish an SSII on Mars without substantial input from Earth. But it depends what you mean by "substantial". I think 800 tonnes (using the Space X minimum model) every two years is indeed substantial for a small colony. In fact I think it would be difficult for a colony of 100 or less to make meaningful use of much more mass. Just think of what you would have on Mars after you'd landed 4000 tonnes of stuff over a decade or so...think of how much power you can generate, the robot rovers, the pressurised rovers, the mining rovers, the industrial 3D printers, the computers, the communications system, glass manufacture facility, the PV manufacturing machines, the mini steel mill, the plastics facility, the Mars brick and cement manufacturing capability... and all for 100 people, so you don't need huge amounts of anything.

Steel is used in prodigious quantities on Earth, it's true but it's not the first material I would look to on Mars. I think of it as initially having more of a niche role in maybe construction supports, and vehicle manufacture. Steel on Earth is probably mostly used in high rise construction and shipping and auto manufacture. There is no real reason why we need to build high on Mars. Even if we move to natural light farming, you don't have to opt for major steel structures - you could glass over terraces and use bonded basalt for frames.

For indoor agriculture, use cut and cover construction (trench with brick arch or flat basalt roof covered in regolith).

GW Johnson · 2018-06-15 12:38:33

Kbd512:

In post 16, it's not 60,000 tons of propellant to send 300 tons, it's 60,000 tons of second-stage (!!!) propellant to send 700-800 tons to Mars (6 landed BFS's plus 1 lost BFS). I didn't bother with totalling first stage propellants, but that's at least another Yamato-class battleship. Maybe 2 or more.

That's just the inevitable cost of using chemical propulsion, as you so rightly have pointed out, multiple times. Fortunately, propellant is cheap. Labor and hardware are what is expensive. Chemical propulsion is what we actually have in hand.

What I calculated, had to do with 6 BFS's landed successfully on Mars, with one ship lost and destroyed. That's 7 ships to refill and send, each requiring 6 tanker flights, for 42 tankers. That's a total of 49 launches. Call it 50 for a round number. Using the wild guess (and wild guess it is) of $200M per launch for a BFR/BFS launch, that's $10B in direct launch costs to succeed in setting down 700-800 tons of "stuff" and maybe 1-2 dozen people on Mars.

My wild-but-educated guess is there's another $5-10B in BFR/BFS development costs before that thing is ready for the trip, plus another $5-10B in equipment development and prove-out testing for that 700-800 tons of "stuff". So, the cost to put a temporary small base on Mars, and do some exploring and some experiments in living off the land, is in the neighborhood of $30B.

That's way less than 10% of old space's estimate of half a trillion, and not very far at all from the $40-50B I guessed for my quite-different update of the 1950's architecture posted over at "exrocketman", an architecture that explores multiple sites, not just one. And which requires no local propellant production to come home.

There's two answers under $50B there, compared to "old space's" corporate welfare price tag of $450-500B to do little more than Apollo-style flag-and-footprints at one site, and only after going all that way there first, without any landing at all. Stupidity incarnate.

Compared to that, propellants balancing the weight of a whole fleet of battleships is chicken feed. Propellant is cheap. Stupidity is what is truly expensive.

GW

Last edited by GW Johnson (2018-06-15 12:41:16)

louis · 2018-06-15 13:35:53

$200 million per launch? Where has that come from???

https://www.nextbigfuture.com/2017/10/s … aunch.html

Space X think they can get down below $7 million. This analyst suggests they could charge $20 - $40 million (but why charge yourself that much?).

https://www.nextbigfuture.com/2017/10/s … aunch.html

If it's $20 million then it's $1 billion not $10 billion in direct launch costs.

GW Johnson wrote:

Kbd512:
In post 16, it's not 60,000 tons of propellant to send 300 tons, it's 60,000 tons of second-stage (!!!) propellant to send 700-800 tons to Mars (6 landed BFS's plus 1 lost BFS). I didn't bother with totalling first stage propellants, but that's at least another Yamato-class battleship. Maybe 2 or more.
That's just the inevitable cost of using chemical propulsion, as you so rightly have pointed out, multiple times. Fortunately, propellant is cheap. Labor and hardware are what is expensive. Chemical propulsion is what we actually have in hand.
What I calculated, had to do with 6 BFS's landed successfully on Mars, with one ship lost and destroyed. That's 7 ships to refill and send, each requiring 6 tanker flights, for 42 tankers. That's a total of 49 launches. Call it 50 for a round number. Using the wild guess (and wild guess it is) of $200M per launch for a BFR/BFS launch, that's $10B in direct launch costs to succeed in setting down 700-800 tons of "stuff" and maybe 1-2 dozen people on Mars.
My wild-but-educated guess is there's another $5-10B in BFR/BFS development costs before that thing is ready for the trip, plus another $5-10B in equipment development and prove-out testing for that 700-800 tons of "stuff". So, the cost to put a temporary small base on Mars, and do some exploring and some experiments in living off the land, is in the neighborhood of $30B.
That's way less than 10% of old space's estimate of half a trillion, and not very far at all from the $40-50B I guessed for my quite-different update of the 1950's architecture posted over at "exrocketman", an architecture that explores multiple sites, not just one. And which requires no local propellant production to come home.
There's two answers under $50B there, compared to "old space's" corporate welfare price tag of $450-500B to do little more than Apollo-style flag-and-footprints at one site, and only after going all that way there first, without any landing at all. Stupidity incarnate.
Compared to that, propellants balancing the weight of a whole fleet of battleships is chicken feed. Propellant is cheap. Stupidity is what is truly expensive.
GW

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