Why colonize Mars and not the Moon?

[rootone]

Well one thing that would be difficult would be attaching the thin rod spoken of on to the surface of Deimos.
Since initially the rod will be rotating along with the rest of the spacecraft .

 

[dkotschessaa]

Well one thing that would be difficult would be attaching the thin rod spoken of on to the surface of Deimos.
Since initially it will be rotating along with the rest of the spacecraft .

I figured you wouldn't start rotating the thing until everything was hooked up.

 

[gleem]

I might have missed this in a previous post but has anybody looked at Robert Zubrin's Mars Direct proposal. He carries some credibility as an aeronautical engineer and entrepreneur and is at least carrying out Earth based studies on the issue of working on Mars. He has a solution for zero gravity at least in transit.

 

[PeroK]

I might have missed this in a previous post but has anybody looked at Robert Zubrin's Mars Direct proposal. He carries some credibility as an aeronautical engineer and entrepreneur and is at least carrying out Earth based studies on the issue of working on Mars. He has a solution for zero gravity at least in transit.

Looking at the Mars Direct website, you get a real feel for the "surviving on the edge" element that is lost on the more optimistic posters on this thread. The pictures on their website should be a reality check. With current technology it is obviously basic expedition living and, hopefully, getting back alive.

 

[lifeonmercury]

With current technology, would it be possible to create breathable air inside a facility using tha gases in the Martian atmosphere? Obviously a lot of nitrogen would be needed in addition to the oxygen.

 

[rootone]

The atmosphere is mainly CO2, it's not hard to extract the Oxygen and dump the Carbon. but is fairly energy intensive.
This technology is already in use for the ISS.
There is some Nitrogen in the atmosphere of Mars, there is also Argon which like Nitrogen is inert chemically if breathed in.

 

[mfb]

Deimos has a day/night cycle of 30 hours, that doesn't sound healthy.

How about artificial gravity?

So we go to Deimos to have a lower gravity, and then we need a mechanism to get artificial gravity? Why not just land on Mars and get gravity for free? Plus CO2, water much more.

The "rotating station on a stick" approach gets impractical with sufficient radiation shielding. It also leads to a large minimal station size, and expansion is problematic.

Looking at the Mars Direct website, you get a real feel for the "surviving on the edge" element that is lost on the more optimistic posters on this thread. The pictures on their website should be a reality check. With current technology it is obviously basic expedition living and, hopefully, getting back alive.

This thread is not about a first mission. It is about a possible global, large-scale effort to establish a permanent and eventually self-sufficient colony.
On Earth, this has been done many times: Groups of people moving to a new, previously uninhabited area, and starting there basically from scratch. Going to Mars permanently will be orders of magnitude more challenging, but we won't arrive with sticks and stones.

 

[PeroK]

This thread is not about a first mission. It is about a possible global, large-scale effort to establish a permanent and eventually self-sufficient colony.
On Earth, this has been done many times: Groups of people moving to a new, previously uninhabited area, and starting there basically from scratch. Going to Mars permanently will be orders of magnitude more challenging, but we won't arrive with sticks and stones.

All previous migrations were to a new part of the Earth, often with better resources for survival and development and everything they needed was freely available: animals to hunt, edible vegetation, water. Mars is not anything like the Earth. The essence of your analogy is that if a European can migrate to Australia or North America to start a new life, then he can surely migrate to Mars. That is an absurd comparison. Not least because nothing we have learned from those migrations helps us to any extent with a migration to Mars. There are many areas on Earth that are not inhabited because of their relative hostility to human life. Mars, by comparison, is many times more hostile to human life than anywhere on Earth.

Anyway, if you don't mind my asking, are you signed up to go?

 

[PeroK]

In the spirit of Private Eye:

Dear Sir, have you ever noticed the resemblance between a Martian Colony and Abu Dhabi?

Mars:

Abu Dhabi:

 

[mfb]

Mars is not anything like the Earth.

I never said that.
Earth was not colonized with 2050 technology, it was colonized by foot and with sailing ships. Surely we can do better with 2050 technology?

Not least because nothing we have learned from those migrations helps us to any extent with a migration to Mars.

If that would be true, why did you ask how to get the first steel foundry on Mars? How did we get the first steel foundry in the Americas? Someone built it. With tools built there, which were probably built with tools built there, and if you go back long enough you arrive at tools from Europe. The details are a lot of engineering work, but they are no fundamental problem.

Your second photo is close to Abu Dhabi 1960, by the way, just without the space suit imitation. Then humans found a reason to build a town there (oil). And see how it looks now, a few decades later.

 

[rootone]

There won't be any oil on Mars unless our assessment of the planet so far is completely mistaken.
There is Iron, but we don't have a shortage of Iron on Earth.

 

[1oldman2]

It would be a miscalculation to write off Elon and SpaceX concerning Mars, that outfit seems to have an impressive learning curve. For the moment let's focus on NASA's research regarding putting 20 metric tons on Mars per landing, using the SLS (PDF recommended).
https://ntrs.nasa.gov/search.jsp?R=...0&Ntk=All&Ntt=mars&Ntx=mode%20matchallpartial
Abstract:
"Current NASA Human Mars architectures require delivery of approximately 20 metric tons of cargo to the surface in a single landing. A proposed vehicle type for performing the entry, descent, and landing at Mars associated with this architecture is a rigid, enclosed, elongated lifting body shape that provides a higher lift-to-drag ratio (L/D) than a typical entry capsule, but lower than a typical winged entry vehicle (such as the Space Shuttle Orbiter). A rigid Mid-L/D shape has advantages for large mass Mars EDL, including loads management, range capability during entry, and human spaceflight heritage. Previous large mass Mars studies have focused more on symmetric and/or circular cross-section Mid-L/D shapes such as the ellipsled. More recent work has shown performance advantages for non-circular cross section shapes. This paper will describe efforts to design a rigid Mid-L/D entry vehicle for Mars which shows mass and performance improvements over previous Mid-L/D studies. The proposed concept, work to date and evolution, forward path, and suggested future strategy are described".

 

[rootone]

The Mars rover Curiosity EDL was fascinating. though based on known stuff that works. That was 1 metric ton.
20x that needs more fingers to be crossed.

 

[mfb]

We have a system that can land 25 ton rockets on a concrete pad with a precision of a few meters, I would expect that modified feet would work on the Martian surface.
Make a guess which company developed it.

There won't be any oil on Mars unless our assessment of the planet so far is completely mistaken.
There is Iron, but we don't have a shortage of Iron on Earth.

That was not my point at all, and we discussed the motivation a few pages ago already.

 

[1oldman2]

Make a guess which company developed it.

http://www.spacenewsmag.com/feature/why-nasa-is-hitching-a-ride-on-red-dragon/
"When NASA and SpaceX announced April 27 that they had modified an existing unfunded Space Act Agreement that involves the company’s "Red Dragon" Mars lander concept, it was, unsurprisingly, SpaceX that got all the attention. No company has ever flown a private Mars lander, and not even NASA has landed a spacecraft as large as SpaceX’s Dragon. Moreover, Red Dragon is the latest sign that SpaceX and its founder, Elon Musk, are serious about pursuing a long-term goal of Mars settlement".

 

[rootone]

Is there not a way where the retro-propulsion trick could be done BEFORE the vehicle gets to Mars' atmosphere.
All it needs then is some very heavy duty parachutes, but then heavy parachutes are heavy, and more fuel needed for the retro.

 

[1oldman2]

Is there not a way where the retro-propulsion trick could be done BEFORE the vehicle gets to Mars' atmosphere.
All it needs then is some very heavy duty parachutes, but then heavy parachutes are heavy, and more fuel needed for the retro.

Here's some reading that can answer your questions better than I can.
http://www.universetoday.com/7024/t...ge-payloads-to-the-surface-of-the-red-planet/
http://mars.nasa.gov/msl/mission/timeline/approach/
http://mars.nasa.gov/msl/mission/technology/insituexploration/edl/

 

[Chronos]

I'm still stuck on the problem of making a Mars mission economical. Even as little as 5K/kg is still enormously expensive given any reasonable payload demands. A moon base launch facility still looks more promising, assuming we can efficiently mine basic minerals and manufacture launch vehicles there. And as already noted, an emergency resupply mission is much more realistic on the moon. No need to shoot for Mars, when the moon is sitting right in our back yard and offers most of what we probably need to leap frog our way across the solar system. Either way, its an effort centuries in the making. I fully expect we will someday look back and chuckle at our primitive flailing efforts to colonize other worlds. I get a faint semblance of hope from that thought. Humanity has historically employed existing technology to bridge the gap towards new technology.

 

[PeroK]

I never said that.
Earth was not colonized with 2050 technology, it was colonized by foot and with sailing ships. Surely we can do better with 2050 technology?If that would be true, why did you ask how to get the first steel foundry on Mars? How did we get the first steel foundry in the Americas? Someone built it. With tools built there, which were probably built with tools built there, and if you go back long enough you arrive at tools from Europe. The details are a lot of engineering work, but they are no fundamental problem.

Your second photo is close to Abu Dhabi 1960, by the way, just without the space suit imitation. Then humans found a reason to build a town there (oil). And see how it looks now, a few decades later.

You really do believe that a few decades from now there will be a city on Mars that looks like Abu Dhabi? Extraordinary!

Out of interest, which country do you think will build it? China, USA, Russia, EU?

 

[lifeonmercury]

USA

 

[PeroK]

I never said that.
Earth was not colonized with 2050 technology, it was colonized by foot and with sailing ships. Surely we can do better with 2050 technology?If that would be true, why did you ask how to get the first steel foundry on Mars? How did we get the first steel foundry in the Americas? Someone built it. With tools built there, which were probably built with tools built there, and if you go back long enough you arrive at tools from Europe. The details are a lot of engineering work, but they are no fundamental problem.

Here are the fundamental differences between Abu Dhabi and Mars. Although, the fact that I have to explain this shows just how far into pure science fiction this thread has gone:

1) Food. Abu Dhabi had no problem with food, because it could import food from anywhere in the world. On Mars,. there is no option to regularly import food from Earth. In fact, Abu Dhabi probably couldn't support itself without the outside world.

2) Construction. Abu Dhabi did not need any factories or manufacturing base, because it could import everything it needed from the existing global manufacturing base. Mars can only import a relatively small amount, at huge cost.

3) Human labour. Abu Dhabi had access to a global labour market, to skilled and unskilled workers at all levels. These workers could be fed and housed using the existing global resources. Mars can only use labour that is transported there at a relatively enormous cost and with little or no flexibility.

4) Travel time. Abu Dhabi is only a few hours flight from Europe and Asia. Mars is approximately 6-12 months away.

5) Medical Facilities. Until Abu Dhabi had built its own hospitals, it had access to existing medical facilities elsewhere for serious illness and emergencies. The early Mars settlements will have access to only basic medical facilities. For an early Mars settler, something like appendicitis (or anything that requires major surgery) will most likely be fatal. Serious cases in construction sites on Earth can be airlifted to existing medical facilities within that or a neighbouring country.

6) Hostility to Human Life. Humans can live, eat and breathe normally in the UAE. On Mars, a significant life support infrastructre is required for all humans based there.

These are fundamental differences. These are differences that make one project feasible (at large, but affordable cost) and another project infeasible both technically, logistically and financially.

You may say that the existing global manufacturing base and supply chain on Earth is irrelevant, as everything on Mars can be built from scratch; but the global supply chain is essential for 21st century projects. Abu Dhabi, or any city on Earth, cannot be build without it. If Abu Dhabi had had to bootstrap itself and build all its own steel foundries and chemical plants first, and excavate its own raw materials from the ground before it could even start building, then it wouldn't and couldn't have been built.

The construction of a city like Adu Dhabi on Earth, without full access to our existing global manufacturing base, is virtually impossible.

The construction of a city like Adu Dhabi on Mars, with limited access to our global manufacturing base, is actually impossible.

 

[Al_]

Here are the fundamental differences between Abu Dhabi and Mars.

The construction of a city like Adu Dhabi on Mars, with limited access to our global manufacturing base, is actually impossible.

But, the thing is, Adu Dhabi was built there because of a valuable resource. Can we find valuable resources on Mars? I guess we could, but shipping them back to markets on Earth is going to be, well, interesting. Let's see what Elon Musk can do with that problem! He is developing the ITS - https://www.physicsforums.com/threads/on-spacex-interplanetary-transport-system.889203/

I figure we would find it much easier to ship back resources that we find on the Moon. Therefore - colonize the Moon first!

 

[Al_]

Why not just land on Mars and get gravity for free?

Just land on Mars? See what NASA says about landing on Mars: -
http://www.universetoday.com/7024/t...ge-payloads-to-the-surface-of-the-red-planet/
“Basically flying into the plume at supersonics speeds, the rocket plume is acting like a nose cone; a nose cone that’s moving around in front of you against very high dynamic pressure. Even though the atmospheric density is very low, because the velocity is so high, the forces are really huge.”
For large craft, it's not a solved problem.

 

[Stavros Kiri]

Out of interest, which country do you think will build it? China, USA, Russia, EU?

Perhaps all together (just like they try to work on the space station) ...
But EU is not a country (yet ...).

 

[Stavros Kiri]

Mars:

Hey, a guy can dream! ... (why not)

Note: picture etc. taken from earlier PeroK post (didn't use official quote because it wasn't meant as a reply to that particular post).

 

[russ_watters]

You may say that the existing global manufacturing base and supply chain on Earth is irrelevant, as everything on Mars can be built from scratch; but the global supply chain is essential for 21st century projects. Abu Dhabi, or any city on Earth, cannot be build without it. If Abu Dhabi had had to bootstrap itself and build all its own steel foundries and chemical plants first, and excavate its own raw materials from the ground before it could even start building, then it wouldn't and couldn't have been built.

The construction of a city like Adu Dhabi on Earth, without full access to our existing global manufacturing base, is virtually impossible.

Agreed. A similar argument is made for other space fantasy projects, like asteroid mining and lunar colonies. It is framed to sound like a chicken-or-the egg problem, when it is really just a chicken or the chicken problem: Building a city (or mining facility) from scratch on Mars or another body is really really hard, and saying it would get easier if you had all the manufacturing base locally is true...but just shifts the problem over a column. Building an industrial base on another world to use to manufacture the parts to build a city is itself a massive (and perhaps even bigger) project like building the colony.

And unlike building a fresh city in the middle of nowhere no Earth, we also have to invent a huge amount of new technology to make it happen. I assume we could, but whereas you can spend a hundred billion dollars and get a shiny new city in the desert, you'd need to spend a trillion dollars (or 10?) just to invent the technology before even starting the project itself!

[edit] For example, a single or small number of exploratory missions to Mars would probably cost at least a trillion dollars. These would do some preliminary research into whether or not it would be possible to farm on Mars. Assuming the results look promising, we'd spend another trillion dollars+ (and a decade or two) just on prototype/test farming operations, which would then tell us if it is feasible to farm on Mars, and how exactly we would do it. Then after that, we could start actually building farms (for trillions more).

 

[russ_watters]

What would be the benefits of not doing this?

I can think of several places I'd rather spend 10 trillion dollars. Like healthcare and my retirement.

 

[Stavros Kiri]

Instead of immigrating to Mars save that money they spend for destroying Earth ... to avoid it! ...

 

[Stavros Kiri]

Why not colonize Earth instead!
[...there's a thought! ... ... Easier too!]

 

[Stavros Kiri]

Earth would be a GREAT Place to start!

It is easier to save or rebuild Earth than to colonize Mars or the moon, for that matter ...

After all both Mars and the moon are just planetary or orbital corpse. Let's not make Earth one too! ...

 

[Stavros Kiri]

The problem with the saving Earth scenario is that we have a multitude of different Governments, Odds of getting everyone to agree 0%

Then how can they save us on Mars or the Moon? They have no logic. Better spend that big money in education to teach everyone logic, something that physicists and mathematicians should be fond of ...

 

[Stavros Kiri]

1+1 = 2, not 1 or else ... (end of story)

 

[Stavros Kiri]

Obviously if the USA was the one to establish Mars as a new colony we wouldn't have to change our philosophy on Gov't. Not a worldly government. What's the problem?

Money spent rarely actually goes to the cause. Very unfortunate

In such a case I would have to agree. But it would be a big responsibility ... either way. Saving humanity is not easy.

 

[mfb]

http://www.spacenewsmag.com/feature/why-nasa-is-hitching-a-ride-on-red-dragon/
"When NASA and SpaceX announced April 27 that they had modified an existing unfunded Space Act Agreement that involves the company’s "Red Dragon" Mars lander concept, it was, unsurprisingly, SpaceX that got all the attention. No company has ever flown a private Mars lander, and not even NASA has landed a spacecraft as large as SpaceX’s Dragon. Moreover, Red Dragon is the latest sign that SpaceX and its founder, Elon Musk, are serious about pursuing a long-term goal of Mars settlement".

No company has ever flown anything outside Earth orbit (apart from discarded rocket stages delivering government-built spacecraft s).

The 25 ton rocket is the Falcon 9 booster. The Dragon capsule is lighter (its mass is a few tons) and it has not landed propulsively yet, although I'm sure it will do so without problems - it is much easier to land than a Falcon 9 booster.

You really do believe that a few decades from now there will be a city on Mars that looks like Abu Dhabi? Extraordinary!

Of course not, and I never said that. You don't have to argue against straw men.
I just think the example of Abu Dhabi is funny because it is one of the good examples how humans go to new places that don't look welcoming - and then make them welcoming.

Just land on Mars? See what NASA says about landing on Mars: -
http://www.universetoday.com/7024/t...ge-payloads-to-the-surface-of-the-red-planet/
“Basically flying into the plume at supersonics speeds, the rocket plume is acting like a nose cone; a nose cone that’s moving around in front of you against very high dynamic pressure. Even though the atmospheric density is very low, because the velocity is so high, the forces are really huge.”
For large craft, it's not a solved problem.

For a 25 ton rocket, it is a solved problem. SpaceX can land their Falcon 9 boosters - they don't have a 100% success rate, but the reliability is going up quickly.

but whereas you can spend a hundred billion dollars and get a shiny new city in the desert, you'd need to spend a trillion dollars (or 10?) just to invent the technology before even starting the project itself!

A trillion dollars R&D that leads to several trillion dollars ROI for the economy. A new city is not R&D money, it is just more of existing things.

For example, a single or small number of exploratory missions to Mars would probably cost at least a trillion dollars.

Source? The highest (!) estimate I saw so far was 500 billions.
SpaceX estimates ~10 billions R&D and maybe a billion for the first mission. Even if the estimate is wrong by a factor 10 it is cheaper than the Apollo program.

 

[russ_watters]

Source? The highest (!) estimate I saw so far was 500 billions.

Based on typical cost overruns for such large projects, that 500 billion estimate is really anywhere between 500 billion and 5 trillion. See, the ISS for an example. Here is a 1998 article lamenting that the ISS would cost 3.6 billion more than the 17.4 billion estimate established in 1993.
http://articles.latimes.com/1998/feb/15/news/mn-20296
And it ended-up costing the USA about 40 billion to build. That doesn't include operations, doesn't include the canceled predecessor program Space Station Freedom and it doesn't include what our international partners paid for their shares.

One only has to apply that kind of cost overrun skepticism to current estimates to reach that figure, and there are some serious critics out there saying it:

We sent nine Apollo crews to the moon (six landed); if we send nine crews to Mars, the total bill would be in the neighborhood of $1.5 trillion. - See more at: http://spacenews.com/op-ed-mars-for-only-1-5-trillion/#sthash.umqtz4NW.dpuf

Given that there is no actual mission plan and we're talking about guesstimates, I'm guesstimating that the guesstimates are unreasonably low, and I think that is reasonable.