Other than PR, what would a Mars manned mission provide that a moon-base and 'cargo flights to the moon' wouldn't?
If the aim is to perfect human survival off-earth, then surely the moon is a better goal. I know we've been to the moon, but only for a few hours. We're nowhere near the tech/cargo transfer needed to put a manned base on it.
Are we going to put a few people on Mars, lose interest in that right away, wait another 40 years and then aim for Europa?
Although its obviously speculative, I'm pretty sure the expert consensus is that Mars is significantly more promising for self-sufficient human colonization than the Moon.
The Martian atmosphere also makes aerobraking possible, meaning spacecraft arriving there need less delta-V. A Dragon2 can land in Mars, but not on the Moon because of this.
Aerobraking is a benefit but is the Dragon really unable to land on the moon? The moon has less gravity (about half) and the velocity difference should be much smaller for a lunar intercept than a Mars intercept.
Dragon doesn't have enough delta-V to land on the moon. The plan for a Mars landing is to use it as a lifting body to keep it above the ground for long enough to shed most of its velocity.
Yes, GP said that already but I'm after the numbers here. How much delta-v the Dragon has? And what are the approximate requirements for Moon vs. Mars landing?
The Dragon 2 has about 1.6 km/s. Apollo had 2.47 km/s to land and 2.22 km/s to take off. Oh, and it would take on the order of 4.5 km/s to take off from Mars and maybe a few hundred to land.
> “With Dragon launched on a Falcon Heavy, it can go pretty much anywhere in the solar system, because that’s a heck of a big rocket,” he continued.
> “Dragon, with the heat shield, parachutes and propulsive landing capability, is able to land on a planet that has higher entry heating, like Mars. It can also land on the Moon, or potentially conduct a Europa mission.”
How does that fit with the statement "Dragon doesn't have enough delta-V to land on the moon"?
If you are talking about human health, it might be that any gravity bellow 0.8g is almost as bad for human health as microgravity. It could be that any gravity above 0.1g is as good as 1g for human health. We simply don't know the format of that curve. We have no data on it even on rodents (the ISS module for that was scrapped). We only know that 1g is good and microgravity is bad. And that very high g is bad too.
First of all, going to Mars is hard. It makes going to the moon look easy. Most missions to Mars have failed - in fact, with fifty years of trying, the USSR and Russia has never had a successful Mars mission. A round trip to the Moon is a week, a round trip to Mars is four years in space.
So if we could do humans on Mars, it would mean that we had learned far more than we used to know. It's like the difference between climbing a hill in your city, and climbing Mt Everest.
Doesn't that argue for doing the moon first? If you say "yeah we've not climbed any hills yet, but we're totally gonna try Everest" that might not show much common sense.
And if the aim is to just try to do the hardest possible thing we can think of, why Mars and not, say Venus?
I think difficulty is a red herring. The other suggested reasons (atmosphere, gravity, water) seem much better reasons.
We've visited for a few hours, this is about putting a colony on it. That's orders of magnitude more difficult. Why do something orders of magnitude more difficult on a planet orders of magnitude more difficult to reach?
As I said, the other answers seemed to give credible suggestions.
Musk is very clear that his plan is to establish a self sustaining colony, not another 'footprints' mission, and not a colony that needs to be sustained via continuous resupply.
Mars has several advantages, you can pretty much google this and get better arguments then I'm able to make here. But here are a few key points.
- Earth like day period, 39 minutes longer versus almost a month longer than earth.
- More stable day-night temperature
- More gravity
- A weak atmosphere (versus none), and the capability to retain a earth like atmosphere.
- Easy access to Water, and CO2. Important for growing plants and making rocket fuel amongst other things.
Just look at people living in the Arctic: everything is imported, basic necessities are expensive, and getting replacements could take weeks.
Now imagine that you're on a different planet, and there are only a few firms that CAN resupply, and they'll only do it if you can compensate them sufficiently.
Better hope the colony is built on a platinum and rhodium mine!
I think "self-sustaining" in the context means that if Earth dissapears, explodes, turns into grey goo, or otherwise becomes unavailable, the Mars colony stands a chance of surviving indefinitely.
Potentially science and technology, things that can be transmitted via radio. Maybe Mars could setup a hollywood style entertainment industry :)
As far as minerals, I really doubt there are any which would be cheaper to mine on mars, load on a rocket and transport back to earth, than to mine directly on earth. Even if you build a space elevator on Mars (which is much easier than building one on earth).
Maybe you could setup a 3 way trade. Even without the space elevator, it's cheaper to ship things from Mars' surface to basically anywhere in the solar system than it is from earth's surface.
So Mars could ship oxygen, water, CO2 filters, building materials, maybe even food to an asteroid station (whatever they can't source locally) and the asteroid station could ship whatever they mine from the asteroid to earth.
We aren't really looking for liquid water [0], as you say that evaporates pretty much instantaneously. Rather we are looking for ice, the pheonix lander confirmed the that this exists naturally on mars [1]. In the worst case water bound to the soil that can be baked out [2].
As for the atmosphere being stripped away, that's not really a concern on time scales humans care about. Though I've heard people talk about setting up a artificial magnet field to reduce the amount of radiation you receive, which should also prevent this.
[0] Well we are, but as a scientific curiosity not as a way to sustain a colony.
In the short term, you are either strip-mining soil to collect ice crystals, which you melt and store inside, or drilling a well (and piping it inside).
You would grow food inside pressurised tents.
In the long term, mars lost its previous atmosphere over billions of years. If you have the technology to rebuild an atmosphere in human timescales (few hundred or thousand years) the atmospheric loss is small enough that it almost becomes a rounding error. Maintaining it should be easy.
...No protective magnetosphere... brutal temperature shifts, and more radiation than you can reasonably survive on the way to Mars. Problems we have not solved yet...
> No protective magnetosphere... brutal temperature shifts
Not a problem in a shielded, climate-controlled shelter, e.g. one partly underground or in a cave.
> more radiation than you can reasonably survive on the way to Mars.
Putting food and water between space and interplanetary astronauts is a popularly-discussed option.
I think you may have been down-voted on your tone. This is an optimistic, bleeding-edge project. Unless you are an expert, it is more appropriate to ask why something isn't a problem than to prematurely declare it as unsolved or unsolvable.
I think the burden is on the person saying, "To mars, very soon!" to explain what they feel has changed, or changing, to allow that to be something other than a one-way, dead-end mission.
If you want optimism for the sake of optimism, Facebook has some lovely mother's groups.
One advantage of Mars to the Moon for a self-sustaining civilization that no-one mentioned is that it is MORE than a few hours away. Any moon base or future economy would be very dependent on earth, while Mars have more incentive to be independent and a real civilization backup.
Without extreme religious persecution at home or the prospect of being extremely wealthy "abroad", will there be that many people interested in going to Mars?
No. Unless Musk has a stupendous trick up his sleeve, this is a unavoidable problem with the whole enterprise. Hard as settling in the new world was, it was tremendously easier (even at the time) to settling on Mars. The best chance for a Mars colony would be an extractable resource that makes it economically sensible to support a non-self-sufficient outpost (i.e., try to become Edmonton, Canada). But there's nothing analogous to oil. The most promising natural resources in space are asteroids.
He wants to go to Mars, so they have at least one rich client that want to pay for the (one way) trip. I'm not sure about the business plan after that, but he has a good track record, so I wouldn't bet against him.
I'm a pretty big Musk fanboy, but I'd bet against him. Walt Disney had a good track record too, but he was another billionaire who couldn't will away human nature in order to create a utopia.
In the end, you just need to be able to find enough people who want to go (there are plenty) and who have the money to pay for the trip (Elon hopes to bring down the cost to such a level that someone selling their home on Earth could afford it in many cases - like $500,000 to move to Mars).
I keep thinking the colonists should have tunnel boring machines. They can then "build" more living and working space as they need it without more supply missions. Of course there's the job of reinforcing and sealing those new tunnels. Tunnels would offer decent protection and a more consistent thermal environment. Heating could be provided from waste heat off a nuclear reactor, or just spent nuclear fuel encased in concrete or something ;-)
A lot of people don't seem to get what he's on about, but the entire history of humans is one of moving around, exploring and settling new places. It would actually be very weird and novel to not settle Mars. The last major settlement was the Americas after Columbus, and that will likely be what happens here, minus the genocide. Things do improve a bit over the years.
The next question is, why Mars in particular? And the simple answer is, it's the closest thing to Earth in the Solar system. The moon is close by, but it's harsh, desolate and resource-poor. Weak gravity, terrible 'days', no atmosphere etc. Proximity is the only thing it has going for it. Mars, on the other hand, is more like the most extreme places on earth - a combination of Antarctica and Atacama - very hard but doable. Once you have regular, not-super-expensive transport, proximity is not such a problem.
The next question is, how would you get there? And this is where all the fun technical talk is happening. You'll need Big Freaking Rockets to escape the Earth's gravity, but then there's a lot of ways it can go after that, for example, can they make a self-fueling MAV in time for 2024? Or it is easier, though more expensive, to just shoot more BFRs then?
Then the question is where will the money for all this come from? Well, I don't imagine SpaceX will be doing this alone. Space agencies spend a bit of money on this, SpaceX makes a profit from their launch business and Musk has said SpaceX will go public in order to fund their Mars colony. Several hundred billion is a lot of money, but spread out over decades and amongst space agencies and companies is doable.
The final question, and one Musk hasn't answered very well IMO is why would millions of people go to Mars? What are the economics of it? Getting a couple of hundred (or thousand) pioneers is not a problem, you'll find tons of people willing to risk everything for far less, but how would you get million person cities up there? The best answer I have is, people will go there because it will be the only place where new things are possible. I think we're starting to see a backlash against "disruption" and it's somewhat justified. Living peacefully with 10 billion humans on one place is hard enough without some of those people rocking the boat. I'm talking about things like AI, human genetic modification, but also just plain old politics, traditions, power structures, etc. Mars would be new wide-open place where you can set up shop and do anything, whether founding new societies or doing dangerous engineering. This would also work very well economically, as Earth would be able to outsource a lot of experimentation and risky activities and there would be a profitable information (not resource) based planetary trade.
50 comments
[ 4.6 ms ] story [ 102 ms ] threadIf the aim is to perfect human survival off-earth, then surely the moon is a better goal. I know we've been to the moon, but only for a few hours. We're nowhere near the tech/cargo transfer needed to put a manned base on it.
Are we going to put a few people on Mars, lose interest in that right away, wait another 40 years and then aim for Europa?
[edit: Thank you all for the responses.]
- Mars has a (thin) atmosphere, mostly made up of CO2 -> good for plant growth. The Moon has none.
- Mars has gravity closer to Earth than the Moon.
- Mars has lots of water, while the moon has possibly just a little?
EDIT: found http://www.mars-one.com/faq/mission-to-mars/why-mars-and-not..., which cites similar and more reasons (although Mars One seems to be pretty much a scam).
Has anyone got numbers for this?
> Musk has said a fully loaded Dragon could even be sent to make a touchdown on the moon or Mars
or https://www.nasaspaceflight.com/2016/04/spacex-debut-red-dra... :
> “With Dragon launched on a Falcon Heavy, it can go pretty much anywhere in the solar system, because that’s a heck of a big rocket,” he continued.
> “Dragon, with the heat shield, parachutes and propulsive landing capability, is able to land on a planet that has higher entry heating, like Mars. It can also land on the Moon, or potentially conduct a Europa mission.”
How does that fit with the statement "Dragon doesn't have enough delta-V to land on the moon"?
Depends on what you mean by close. 0.38 is closer to 16.7 than 1, but any improvement on that is important
So if we could do humans on Mars, it would mean that we had learned far more than we used to know. It's like the difference between climbing a hill in your city, and climbing Mt Everest.
And if the aim is to just try to do the hardest possible thing we can think of, why Mars and not, say Venus?
I think difficulty is a red herring. The other suggested reasons (atmosphere, gravity, water) seem much better reasons.
As I said, the other answers seemed to give credible suggestions.
Mars has several advantages, you can pretty much google this and get better arguments then I'm able to make here. But here are a few key points.
- Earth like day period, 39 minutes longer versus almost a month longer than earth.
- More stable day-night temperature
- More gravity
- A weak atmosphere (versus none), and the capability to retain a earth like atmosphere.
- Easy access to Water, and CO2. Important for growing plants and making rocket fuel amongst other things.
Now imagine that you're on a different planet, and there are only a few firms that CAN resupply, and they'll only do it if you can compensate them sufficiently.
Better hope the colony is built on a platinum and rhodium mine!
Yes, it's a hugely ambitious goal.
- mining industry
- chemical industry with thousands of end products.
- biochemical industry (medicines, plastics etc.)
- microprocessor fab and IC fabrication
- indefinitely sustained biosphere
- manufacturing industry for different high-end products, including rockets, instruments etc. and ability to maintain them.
I think you need large city with maybe 500,000 people at minimum with current technology.
As far as minerals, I really doubt there are any which would be cheaper to mine on mars, load on a rocket and transport back to earth, than to mine directly on earth. Even if you build a space elevator on Mars (which is much easier than building one on earth).
Maybe you could setup a 3 way trade. Even without the space elevator, it's cheaper to ship things from Mars' surface to basically anywhere in the solar system than it is from earth's surface.
So Mars could ship oxygen, water, CO2 filters, building materials, maybe even food to an asteroid station (whatever they can't source locally) and the asteroid station could ship whatever they mine from the asteroid to earth.
We aren't really looking for liquid water [0], as you say that evaporates pretty much instantaneously. Rather we are looking for ice, the pheonix lander confirmed the that this exists naturally on mars [1]. In the worst case water bound to the soil that can be baked out [2].
As for the atmosphere being stripped away, that's not really a concern on time scales humans care about. Though I've heard people talk about setting up a artificial magnet field to reduce the amount of radiation you receive, which should also prevent this.
[0] Well we are, but as a scientific curiosity not as a way to sustain a colony.
[1] http://www.nasa.gov/mission_pages/phoenix/news/phoenix-20080...
[2] http://www.space.com/22949-mars-water-discovery-curiosity-ro...
In the long term, mars lost its previous atmosphere over billions of years. If you have the technology to rebuild an atmosphere in human timescales (few hundred or thousand years) the atmospheric loss is small enough that it almost becomes a rounding error. Maintaining it should be easy.
Not a problem in a shielded, climate-controlled shelter, e.g. one partly underground or in a cave.
> more radiation than you can reasonably survive on the way to Mars.
Putting food and water between space and interplanetary astronauts is a popularly-discussed option.
I think you may have been down-voted on your tone. This is an optimistic, bleeding-edge project. Unless you are an expert, it is more appropriate to ask why something isn't a problem than to prematurely declare it as unsolved or unsolvable.
If you want optimism for the sake of optimism, Facebook has some lovely mother's groups.
Water is easy to get on mars, so there's chance man can live independently on mars.
I heard that NASA already found a way to make water from moon rock, but that sounds … magical
https://en.wikipedia.org/wiki/EPCOT_(concept)
Remember how crowdfunding raised over 100 million dollars for Star Citizen - a video game!
I am amazed Musk or even NASA itself has not tried crowdfunding the colonization of Mars..
I would hope that is because few believed Mars One was a viable venture. Musk's vision should be much more convincing.
The next question is, why Mars in particular? And the simple answer is, it's the closest thing to Earth in the Solar system. The moon is close by, but it's harsh, desolate and resource-poor. Weak gravity, terrible 'days', no atmosphere etc. Proximity is the only thing it has going for it. Mars, on the other hand, is more like the most extreme places on earth - a combination of Antarctica and Atacama - very hard but doable. Once you have regular, not-super-expensive transport, proximity is not such a problem.
The next question is, how would you get there? And this is where all the fun technical talk is happening. You'll need Big Freaking Rockets to escape the Earth's gravity, but then there's a lot of ways it can go after that, for example, can they make a self-fueling MAV in time for 2024? Or it is easier, though more expensive, to just shoot more BFRs then?
Then the question is where will the money for all this come from? Well, I don't imagine SpaceX will be doing this alone. Space agencies spend a bit of money on this, SpaceX makes a profit from their launch business and Musk has said SpaceX will go public in order to fund their Mars colony. Several hundred billion is a lot of money, but spread out over decades and amongst space agencies and companies is doable.
The final question, and one Musk hasn't answered very well IMO is why would millions of people go to Mars? What are the economics of it? Getting a couple of hundred (or thousand) pioneers is not a problem, you'll find tons of people willing to risk everything for far less, but how would you get million person cities up there? The best answer I have is, people will go there because it will be the only place where new things are possible. I think we're starting to see a backlash against "disruption" and it's somewhat justified. Living peacefully with 10 billion humans on one place is hard enough without some of those people rocking the boat. I'm talking about things like AI, human genetic modification, but also just plain old politics, traditions, power structures, etc. Mars would be new wide-open place where you can set up shop and do anything, whether founding new societies or doing dangerous engineering. This would also work very well economically, as Earth would be able to outsource a lot of experimentation and risky activities and there would be a profitable information (not resource) based planetary trade.