NASA Wants Spacecraft For Mars Return Trip 193
coondoggie writes "If we ever do get to Mars, getting home might prove to be as difficult. NASA today selected three companies — Alliant Techsystems, Lockheed Martin and Northrop Grumman — to being the task of defining the spacecraft that will leave Mars, presumably at first loaded with red planet rock samples, then later possibly humans — for a safe trip back to Earth. The engineering challenges those three companies face are immense."
We better not get double billed (Score:3, Funny)
We don't pay for any bids that specify the same ship design be used for the return as was used during the departure.
Re: (Score:2)
It can't be. For one thing, you've used up almost all of your mass as fuel by the time you land at Mars.
Then there's the pesky little detail that most people ignore, that Mars isn't a sister planet to Earth, but a tiny little ball that has more in common with Mercury and large moons than with Earth and Venus. You only need a tiny fraction of the boost to lift of from Mars compared to Earth.
Pretty obviously they couldn't be (Score:2)
If I were to design it (Score:3, Insightful)
Re: (Score:2)
Why bother making the trip twice? The same ship that carries everything to mars can be used as a fueling depot in mars orbit for the lander to return to earth.
Re: (Score:2)
Essentially it may end up being a six stage rocket we are talking about.
For a human transport I think that the following concept is what's needed.
Stage 1 & 2 are to leave Earth.
Stage 3 is for the transit phase to Mars.
Stage 4 is for the return trip.
Stage 5 is for landing.
Stage 6 is for departure from Mars to Mars orbit.
At arrival at Mars Stage 3 is discarded, Stage 4 left in orbit and Stage 5&6 are landed, at launch Stage 5 will be used as launch pad for Stage 6. However Stage 3 could still be usefu
Re: (Score:2)
Yeah this is very similar to what I was picturing.
No matter how you slice it, I think, a round trip to mars would be the largest/longest/most expensive/most complicated/quintessentially fantastic trip in human history.
Yet i'm 27 and afraid I may not live to see it.
Re: (Score:2)
"Congratulations, you just re-invented Apollo!"
It's not as if that idea didn't work.
Re: (Score:2)
The problem is (if I understand the orbital mechanics right; IANARS) that the launch window for getting to mars, or back, is rather small and occurs but rarely. If you send a rocket TO mars, it won't immediately come back, because the window to START travelling is shorter than the time it takes to get there.
Additionally, the fuel needed in transit is actually much less than the fuel needed to get into and out of those kind of orbits--because space has no force opposing inertia. Getting a load from the sur
Re: (Score:2)
And yes. Despite much smaller gravity well that Mars has, I guess it makes more sense to leave fuel for return trip in orbit than to take it to Mars surface. This way, if something goes wrong with the lander, you
The ferry (Score:2)
Re: (Score:2)
Re: (Score:2)
0. Get fuel tanks outside Earth gravity field
0.1. land them on mars.
1.1/ Get spacecraft1 outside Earth gravity field
1.2/ Get to Mars
1.3/ Descent
1.35/ Refuel with tanks
1.4/ Get outside Mars gravity field
1.5/ Get to Earth
1.6 Descent
All this with a smaller ship.
One Way (Score:4, Interesting)
Re: (Score:2)
Personally, I would be much more interested in a sample return mission than a Mars colony.
The amount of materials you need to send over to establish a viable colony are also staggering. A small sample return mission is probably simpler.
Re: (Score:2)
If it's to do scientific analysis on the rock, then it's cheaper to send robotic equipment to Mars and do the analysis there.
In the real world, scientific analysis isn't done by a few instruments like a tricorder. You don't wave the box and science comes out. Real scientific instruments often have some flexibility, but in the end, they are all limited in what they can do. A space probe to another world can only do a few things.
But OTOH, if you bring those samples to Earth, then you can bring to bear the entire power of human science, the massive infrastructure that can do more with a sample from Mars than a lifetime of probes
Re: (Score:2)
It would be cheaper to devlop and send
Re: (Score:2)
To send an instrument to mars you have to make your instruments tough enough to survive going to mars and have a VERY high chance of working. That means they will likely be a long way from state of the art at the time the mission is planned and even further behind by the time they actually make it to mars. Then a few years later when you want readings from newer better equipment you have to start from scratch.
With a sample return mission you can analyse with the latest equipment and provided you bring back
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Valentina Tereshkova (first woman in space) said recently she'd be happy to volunteer for a one-way trip to Mars.
And, in a few weeks, she'll be 74 years old.
I'm sure you could find a bunch of people who would be willing to volunteer. The question is whether or not these people would actually be worth sending to Mars. I'd rather send a bunch of scientists (geologists, biologists, etc.) who are interested in doing research and returning to Earth in order to publish their findings than a bunch of suicidal thrill-seekers who are looking for some way to get their names in the history books.
Re: (Score:2)
Well, we can better analyze the samples they collect back on earth. Also, travelling the Mars will be hard on the astronauts, and the experience they gain would be invaluable for future missions.
Oh Jesus, not this again (Score:2)
The idea of a self-sustaining Martian colony is beyond retarded. It costs something like a million dollars/kg to get stuff to Mars. To get a colony going would require millions of kilograms of stuff. Then anything you manufactured there would have to be transported back to earth to be sold - again with transport costs $1M/kg (or more, as building return rockets on Mars would no doubt be exceedingly expensive). And Mars is made of the same stuff as earth - silicates, iron, etc. What the hell could you possib
Re: (Score:2)
Ha, right. Did you maybe miss what happened to the shuttle program when some astronauts got killed? NASA sending a crew to slowly die on Mars on evening television would probably be the end of the whole US space program.
And die they would. We're nowhere near having the capability to put a self sustaining base on Mars.
Re: (Score:2)
I would guess that about half the Presidents and most of the Senators of the last 50 years would consider the cost of a one-way Mars mission a small price to pay to be able to defund NASA for good.
So.... (Score:3)
...all the tens of thousands of people that would be employed to make this happen... I guess none of they money spent by them would go back into the country? They would spend it all offshore right? Riiiiiight...
Re: (Score:2)
we can accomplish almost all the same goals via robotic exploration
And if you can't, it means you need to build better robots. You need robots for any work on Moon and Mars anyway - there are no cheap laborers there, and every minute outside (esp. on the Moon) is dangerous (radiation, micrometeorites, damage to spacesuits, etc.)
However exciting a manned trip to Mars may be, it is certainly not justified at this point in time. Humans would be needed there only if we are pretty sure that there is sentien
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
History has shown over and over that expansion into new areas returns money. BIG money. THat is how EU became large from an economic POV.
I think you will find that the EU became large from an ecomomic POV because it amalgamated some of the world's largest individual economies, such as Germany's Italy's and France's.
There isn't a lot Mars will add to earth's GDP (although that creepy face may indicate otherwise) in the short, or even medium term, even if we colonise it.
Re: (Score:2, Insightful)
The potential payoff is acquiring an entire planets worth of resources. Calculate that into your risk analysis.
It actually goes farther than that. If we developed the technology for a mars trip it makes exploiting NEO's and the asteroid belt trivial.
Every single generation will be able to say the same thing as you. Technology does not magically invent itself. There is no time like now to start working towards the ultimate goal of our species.
Re: (Score:2)
The potential payoff is acquiring an entire planets worth of resources.
What resources exist on Mars that would justify the cost of bringing them back to Earth?
So long as a trip between Mars and Earth costs millions of dollars a kilo, we're extremely unlikely to find anything that has enough value to justify the cost.
Re: (Score:2)
There is no need to ship anything -- the resources will have value for people who are on Mars.
What 'people who are on Mars'?
Re: (Score:2)
The one-way volunteers, or people from the sustainable off planet colony. See the first post of the thread.
The post I was replying to was talking about 'acquiring another planet's resources'. What value do those resources have to the people on Earth who are apparently going to pay for these 'volunteers' to go there?
You can't use Mars resources to justify the cost of going to Mars if the only use for those resources is to sustain those people who are going to Mars.
In the military... (Score:2)
Re: (Score:2)
True, we don't have the money.
We should leave Mars exploration and colonization to China.
Re: (Score:2)
Who even has the money to pay for a Mars boondoggle, one-way or not?
Where's the payback for the billions of dollars this will require? A new flavor of Tang? Another cool pen that writes upside down? Seriously, where is the cost-benefit analysis, who can possibly show that the price is justifiable to the taxpayer?
We, along with Russia, simply do not have the money for such a frivolous project, even if the technical hurdles were surmountable. This is just another NASA pipe dream, stoked by science fiction and movie lore. Every dollar spent pursuing this project is a dollar flushed straight down the toilet (or, as some would say, graft for the contractors like Lockheed and Grumman who get the $ and don't have to produce anything tangible)
Too many people have forgotten that landing a man on the moon was not driven by science, it was driven by politics -- specifically the fear of the Soviet Union. The Russians put the first man in space and the US was afraid that if the Soviet Union got to the moon it would somehow give them some sort of military advantage. With that (stupid) fear out of the way, we can now see that sending people to the moon or Mars is a pointless waste of money.
Re: (Score:2)
We, along with Russia, simply do not have the money for such a frivolous project,
well print some more then.
Re: (Score:2)
Keynesian economics dictate that direct government spending is the most efficient economic stimulus, followed closely by tax cuts. Even if you think such a project is a waste of money, it isn't -- the hiring of American engineers, American workers, American astronauts etc ultimately returns *more* tax dollars to the gover
Re: (Score:2)
Keynesian economics dictate that direct government spending is the most efficient economic stimulus, followed closely by tax cuts.
What does reality "dictate"? That's what counts. For example, Japan has been pursuing hardcore Keynesian stimulus plans for the last twenty years. Hasn't helped them.
The Space Shuttle program alone employs 25,000 people *directly*.
That's a variation of the broken window fallacy. If we didn't have those people working on the Shuttle, they'd be working on something productive instead. End result is that US society misses out on the value of their labor.
Re: (Score:2)
"That's a variation of the broken window fallacy. If we didn't have those people working on the Shuttle, they'd be working on something productive instead. End result is that US society misses out on the value of their labor."
Given current world economics is quite arguable that the best way for the USA to expend money is in high tech research, being the effort of going to Mars probably a very good example.
Re: (Score:2)
Re: (Score:2)
Oh, the old "broken window fallacy" fallacy... :-P
Now seriously, two things:
Re: (Score:2)
"where is the cost-benefit analysis, who can possibly show that the price is justifiable to the taxpayer?"
Not everything must be thought in terms of ROI. VOI is even more useful for strategic planning. And the strategic value for Humankind of being able to reach one planet apart from Earth is immense.
Re: (Score:2)
And the strategic value for Humankind of being able to reach one planet apart from Earth is immense.
Well start with a list already. Getting men on the moon was a waste of money, they would have got better science out of the money by using even 1960s robotics. Today robotics is even better. So what "immense" strategic value do we get from single human mission that does many many times less than the 100s of robotic missions that could have been sent instead?
What "immense" value do I get when the people send die before they get there?
Re: (Score:3)
"We, along with Russia, simply do not have the money for such a frivolous project"
Still you had some 1,2 to 2,4 trillions to spend in wars since 2001. Obviously Iraq and Afghanistan are not so frivolous projects.
"Where's the payback for the billions of dollars this will require? A new flavor of Tang? Another cool pen that writes upside down? Seriously, where is the cost-benefit analysis, who can possibly show that the price is justifiable to the taxpayer?"
There was a time when a US citizen could have a sen
Re: (Score:2)
Re: (Score:2)
Who even has the money to pay for a Mars boondoggle, one-way or not?
Where's the payback for the billions of dollars this will require? A new flavor of Tang? Another cool pen that writes upside down? Seriously, where is the cost-benefit analysis, who can possibly show that the price is justifiable to the taxpayer?
We, along with Russia, simply do not have the money for such a frivolous project, even if the technical hurdles were surmountable. This is just another NASA pipe dream, stoked by science fiction and movie lore. Every dollar spent pursuing this project is a dollar flushed straight down the toilet (or, as some would say, graft for the contractors like Lockheed and Grumman who get the $ and don't have to produce anything tangible)
You and your kin are why humans will one day become extinct.
Re: (Score:2)
Instead we'll just watch them asphyxiate when their O2 runs out.
Why would their O2 run out? The Martian atmosphere has a lot of carbon dioxide in it. You can pull oxygen from that. And the tools that can do that, often produce human-edible food in the process. You know what terraforming they need to do? Build some stuff such as airtight living quarters, greenhouse, etc.
Oh, right (Score:2)
It costs at least a million dollars/kg to get stuff to Mars. And the stuff they'd need would include, at a minimum, some kind of power generation system (nuclear or solar), lighting, heat, water purification equipment, tools & materials needed to do farming, seeds, startup food, air and water for themselves, clothing, tools & materials to build shelters, at least minimal furniture, minimal domestic implements (spoons, dishes, etc), comm and IT gear (presumably they'll need to phone home to earth per
Re: (Score:2)
It costs at least a million dollars/kg to get stuff to Mars. And the stuff they'd need would include, at a minimum, some kind of power generation system (nuclear or solar), lighting, heat, water purification equipment, tools & materials needed to do farming, seeds, startup food, air and water for themselves, clothing, tools & materials to build shelters, at least minimal furniture, minimal domestic implements (spoons, dishes, etc), comm and IT gear (presumably they'll need to phone home to earth periodically) bulk quantities of water (or equipment to mine water from Martian soils) for irrigating crops, some sort of capital equipment if they're to manufacture anything (probably heavy)... Are you putting this on your Visa card? Because I'm not keen on shelling out the bucks for it.
A few things to note. First, that's mass. Sure, we could pay eye-popping sums of money or we could first work on making the trip cheaper (which is currently what's going on). Second, a good portion of that list can be made after they reach Mars.
Third, even now prices aren't a million dollars per kg. For example, the Mars Exploration Rovers had build and launch costs that added up to roughly a million dollars per kg, but this included a lot of stuff optimized to a ridiculous extreme including an elaborat
Re: (Score:2)
First, If there's anything "going on" that shows any promise of significantly reducing costs to get to Mars, I'm not aware of it. Got a link? Second, if they're going to make the stuff they need on Mars, then they're going to need the equipment it would take to do th
and... (Score:2)
Pale red dot (Score:4, Interesting)
"There does not seem to be sufficient short-term profit to motivate private industry. If we humans ever go to these worlds, then, it will be because a nation or a consortium of them believes it to be to its advantage" -Sagan
Re: (Score:2)
"There does not seem to be sufficient short-term profit to motivate private industry. If we humans ever go to these worlds, then, it will be because a nation or a consortium of them believes it to be to its advantage" -Sagan
No, it will be because the cost of getting there has dropped into a range that rich tourists can afford. Otherwise there's no particularly good reason to go to Mars when all the resources we need to live in space are floating around waiting for us in asteroids and comets.
Re: (Score:2)
Well, part of the cost is the *time* involved. It's doubtful a Mars tourist trip would be feasible in even a dozen generation's time.
A spinning roulette wheel orbital casino a la Cowboy Bebob would be the best bet. It'd be faster and easier to get to as well as generate artificial gravity, making it easier to keep hold of your cards and chips, and having sex with space hookers... sex in zero-g is not sexy at all.
Re: (Score:2)
Well, part of the cost is the *time* involved. It's doubtful a Mars tourist trip would be feasible in even a dozen generation's time.
Bill Gates could probably afford it today if he was willing to take significant risks; NASA might need a trillion dollars to fly to Mars and back, but a private company could do it for much less. Falcon-9 is supposed to cost about $100,000,000 to put 32 tons into LEO, so you could launch a thousand ton spacecraft (most of which would be fuel) for about $3 billion... even if that ship costs $10 billion itself, that totals less than a quarter of what Gates is reportedly worth. And while 'the richest few peopl
Re: (Score:2)
Sure, they can buy seats on the Soyuz, which has been around forever and always been very economically efficient... or SpaceShipOne/Two which are X-15 / X-20 ripoffs (which are Me-263 and some German rocket bomber ripoffs...) anyway, the X-15 / X-20 were always relatively cheap, it's just that the rocket plane
Re: (Score:2)
Yeah, but is that technology going to get cheaper? The fundamentals of rocket science haven't changed since the days of Sergei Korolev and Wernher von Braun. There's no Moore's law in effect here.
The fundamentals of flight haven't changed since the Wright Brothers and the cost of the aircraft has increased, but the cost of travel is much lower.
To give an obvious example of where improvements will come from, the Falcon rockets are designed to be reusable; there's little point doing that if you fly twice a year, but there's a lot of point if you fly a thousand per year. Few people would be able to afford to fly across the Atlantic if the airliner could only make one trip.
Similarly, having to launch a
This is the key assumption (Score:2)
Your analogy isn't really getting the job done for you. Sure, the price of air travel has gone down - but it's still not cheap. It's still much, much cheaper, for example, to get something shipped UPS ground than UPS overnight. And for bulk quantities of stuff, forget it. Air's not an option for resupplying your coal fired power plant, for example.
The situation is even worse with respect to space. Prices aren't really coming down at all, and there really aren't any technological breakthroughs on the horizon
Re: (Score:2)
Your analogy isn't really getting the job done for you. Sure, the price of air travel has gone down - but it's still not cheap. It's still much, much cheaper, for example, to get something shipped UPS ground than UPS overnight. And for bulk quantities of stuff, forget it. Air's not an option for resupplying your coal fired power plant, for example.
The situation is even worse with respect to space. Prices aren't really coming down at all, and there really aren't any technological breakthroughs on the horizon as far as anyone can tell. Economies of scale, if you can achieve them, will only get you so far. You're going to need something that makes you some money "out there", and so far, no one has any particularly plausible ideas. The terrestrial planets are all made of the same stuff earth is, and no matter how cheap you make space travel, it's never going to be so cheap that mining is more economically done in space. Asteroids are the same deal. Comets: slushballs. Gas giants: hard to even imagine what you could recover or how to do it. And if you can't figure out what can be economically recovered, you probably can't even get the economy of scale.
Ok, I'll bite. Why do we need to? We've already established that there's no money in it. Carl Sagan seems to be casting about for a reason to do it in the quote. So why? This is really the heart of the matter. You can't just wave your hands and say "we need to get into space... just because". Someone needs to identify the actual benefits - and so far, they seem pretty slim.
The actual benefit of advancing space-faring technology is the possibility that humans may one day establish a self-sustaining off-world colony. This is important, to some of us, because it makes extinction much less likely.
If you do not care about the extinction of humanity, then I understand not giving a damn about space travel. If you do care, space travel should be pretty important to you.
Re: (Score:2)
Yeah, but is that technology going to get cheaper?
Sure, launch frequency is the great, big, unexploited economy of scale. Any currently operating space vehicle would be much cheaper per launch, if you doubled the number of launches.
Cost of manufacture has dropped significantly over the decades too.
Challenges (Score:5, Insightful)
"The engineering challenges those three companies face are immense"
The bureaucratic challenges will be even more so.
Big companies will design an expensive approach (Score:5, Insightful)
These big contractors will never come up with an efficient solution. It is against their interests. They will design some very capital intensive approach. Then they will bid on the contracts to build it.
It will take a startup company to come up with a innovative and viable approach.
Re: (Score:2)
Re: (Score:3)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Re: (Score:2)
Yes, it is indeed complex. But I will point out that it took small startups to figure out how to create low cost launch vehicles. The big contractors just don't have that mindset. See this article about Elon Musk: http://www.guardian.co.uk/technology/2010/aug/01/elon-musk-spacex-rocket-mars [guardian.co.uk]
From that article:
Immense?! (Score:2)
To paraphrase - "I think you underestimate their chances".
From an engineering standpoint, the challenges are similar to the Apollo moon missions.
What's new is size and weight for the extra storage capacity needed for fuel, food, oxygen, etc; and space for the extra living quarters.
In fact, I'd say you could do it with 3 launches from Earth to put up a propulsion module, living quarters module (the "RV" section and the mars lander module.
Assemble them in orbit like the Apollo missions did, go to Mars, drop t
Re: (Score:2)
Well... except for the fact that we don't HAVE the heavy lift tech anymore...
Heavy lift is a crazy boondoggle; there's very little market for it and as a consequence it ends up far more expensive than using multiple smaller launchers.
The way to reduce costs is to increase flight rates so that reusability becomes worthwhile and viable, not to stick everything on top of a huge rocket that flies twice a year, costs billions of dollars every time, and destroys your entire multi-billion dollar spacecraft if it fails. That's particularly true for fuel, where you don't much care whether yo
Re: (Score:2)
Heavy lift is a crazy boondoggle
Yeah, that Wernher von Braun... always concerned with profits and personally designing boondoggle after boondoggle.
The way to reduce costs is to increase flight rates so that reusability becomes worthwhile and viable, not to stick everything on top of a huge rocket that flies twice a year, costs billions of dollars every time, and destroys your entire multi-billion dollar spacecraft if it fails.
We had something like that, and it's going to cease to exist in June. It could carry quite a bit of cargo, but not enough for a lunar or martian mission. You're also going to leave stuff behind that's not reusable on any type of super-long distance space trip; "reusable" only really applies to stuff within Earth's atmosphere. You need big freaking rockets to get to Mars and back, and that's
Re: (Score:2)
Yeah, that Wernher von Braun... always concerned with profits and personally designing boondoggle after boondoggle.
Indeed. A large part of the problem with manned spaceflight is that people continue to follow von Braun's dreams even though experience has shown that he was wrong.
We had something like that, and it's going to cease to exist in June. It could carry quite a bit of cargo, but not enough for a lunar or martian mission.
The shuttle was at best refurbishable and required huge amounts of labour and lots of new hardware for each flight. Falcon 9 Heavy should cost about a tenth of the price of a shuttle launch while carrying the same payload, and that's even before they start recovering the stages for refurbishment.
Re: (Score:2)
Mars also has a thin atmosphere, which creates some unique challenges. A rocket assisted landing is fairly easy in a vacuum, but a lot harder while flying supersonic through the atmosphere. On the other hand, the atmosphere is too thin for aerobraking with a heat shield or parachutes.
What makes it even harder is that Mars is the only place to practice.
Re: (Score:2)
On the other hand, the atmosphere is too thin for aerobraking with a heat shield or parachutes.
That'll be news to the probes that have landed there using aerobraking and parachutes.
Ok, they needed either rockets or inflatable balloons for the final touchdown, but most of the braking was performed by the atmosphere. Similarly, you can use the atmosphere to perform much of the braking required to get into orbit, which further reduces fuel requirements.
Re: (Score:2)
Those were all very small and light, and able to withstand the considerable forces of surface impact. This method does not scale up to the size and mass required for a return rocket.
Please see the Case for Mars... (Score:2, Interesting)
...Robert Zubrin 1996 http://en.wikipedia.org/wiki/The_Case_for_Mars for a decent affordable, credible, realistic and possible plan.
Then, if anyone reading this knows Elon Musk, please send him a copy.
Re: (Score:2)
I'm pretty sure Elon knows Zubrin. Its really a quite small community, and I've been to conferences where they are both there. And I'm pretty sure they agree on a lot of things, including the desire to extend a human presence to that planet.
I'm not sure what you're getting at.
Re: (Score:2)
For sufficiently fuzzy values of "affordable", "credible", and "realistic" - sure. In the real world, not so much.
Zubrin consistently treats things that exist as laboratory prototypes as if they were ready to be deployed off-the-shelf. He consistently treats questions that we don't even know enough about to quantify the known unknowns clearly as if they are long solved a
Re: (Score:2)
One of the bigger reasons for the dislike is that Zubrin wants a 2 way mission. Musk is
we need a way to make fuel on mars better to plan (Score:2)
we need a way to make fuel on mars better to plan for a one way or very long term trip to Mars and maybe just a shouter term cargo only return.
Re: (Score:2)
Send some unmanned cargo & fuel-only runs out to Mars orbit to refuel the manned mission for the return trip. The problem is not the technology, it's the political will to fund it. When politicians are in charge of your budget, you wind up with decisions made by cowards.
I know how do do it! (Score:2)
Re: (Score:2)
Why even send the fuel? Build it from the environment once you get there. A phased array antenna could avoid the need for a de-spun bus on the vehicle as well.
Of course, the really hard technical part (not to diminish the political and psychological challenges) is the landing on the surface. There is no 'best practice' for Mars EDL (Entry/Descent/Landing), and landing something big enough to hold people is very much an open problem.
Getting ahead of themselves (Score:5, Interesting)
Before they start working on how to get OFF of Mars they need to figure out how to get ON Mars. A couple of years ago I found this article (sorry, lost the original link).
Getting Large Payloads to the Surface of Mars
by Nancy Atkinson
July 17th, 2007
Some proponents of human missions to Mars say we have the technology today to send people to the Red Planet. But do we? Rob Manning of the Jet Propulsion Laboratory discusses the intricacies of entry, descent and landing and what needs to be done to make humans on Mars a reality.
There’s no comfort in the statistics for missions to Mars. To date over 60% of the missions have failed. Even among those who have devoted their careers to the task, mention sending a human mission to land on the Red Planet, with payloads several factors larger than an unmanned spacecraft, and the trepidation grows even larger.
Why? Nobody knows how to do it.
Surprised? Most people are, says Rob Manning the Chief Engineer for the Mars Exploration Directorate and presently the only person who has led teams to land three robotic spacecraft successfully on the surface of Mars. "It turns out that most people aren’t aware of this problem and very few have worried about the details of how you get something very heavy safely to the surface of Mars," said Manning.
He believes many people immediately come to the conclusion that landing humans on Mars should be easy. After all, humans have landed successfully on the Moon and we can land our human-carrying vehicles from space to Earth. And since Mars falls between the Earth and the Moon in size and atmosphere, it should be easy. "There’s the mindset that we should just be able to connect the dots in between," said Manning.
The real problem is the combination of Mars’ atmosphere and the size of spacecraft needed for human missions. While the Apollo lunar lander weighed approximately 10 metric tons, a human mission to Mars will require three to six times that mass, given the restraints of staying on the planet for a year. Landing a payload that heavy on Mars is currently impossible, using our existing capabilities. "It’s this ugly, grey zone", said Manning, "There’s too much atmosphere on Mars to land heavy vehicles like we do on the moon, using propulsive technology and there’s too little atmosphere to land like we do on Earth. Until we come up with a whole new system, landing humans on Mars will be an ugly and scary proposition."
In 2004 NASA organized a Road Mapping session to discuss the current capabilities and future problems of landing humans on Mars. Manning co-chaired this event and the major conclusion that came from the session was that no one has yet figured out how to safely get large masses from speeds of entry and orbit down to the surface of Mars.
"We call it the Supersonic Transition Problem," said Manning. With our current capabilities, a large, heavy vehicle, streaking through Mars’ thin atmosphere only has about ninety seconds to slow from Mach 5 to under Mach 1, re-orient itself from a being a spacecraft to a lander, deploy parachutes to slow down further, then use thrusters to translate to the landing site and finally, gently touch down.
When this problem is first presented to people, the most offered solution, Manning says, is to use airbags, since they have been so successful for the missions that he has been involved with; the Pathfinder rover, Sojourner and the two Mars Exploration Rovers (MER), Spirit and Opportunity.
But engineers feel they have reached the capacity of airbags with MER. "It's not just the mass or the volume of the airbags, or the size of the airbags themselves, but it's the mass of the beast inside the airbags," Manning said. "This is about as big as we can take that particular design."
In addition, an airbag landing subjects the payload to forces between 10-20 G’s. While robots can withstand such force, humans can’t. This doesn’t mean airbags will never be
wormhole (Score:2)
1. Launch craft to Mars
2. Land on Mars
3. Assemble pre-fab transfer gate
4. Activate transfer gates on Earth and Mars
5. Walk back to Earth
6. Start selling access to gateway
NASA could single handedly pay off the US debt this way
Might want to budget a bit extra for the whole "develop gateway technology" portion of the schedule prior to launch
nuclear ion engines (Score:2)
Re: (Score:2)
It does have the problem of not having enough thrust to make the trip at all in a reasonable time frame.
Which is a great idea... except there isn't enough air for parachutes to slow a payload the size of the lander down enough, and airbags produce G and shock loads way above what a human can tolerate... Not t
WHich is the wrong way (Score:2)
WRONG. The nuke generates the heat which can create steam, and drive a turbine. BUT, you have to dump the
It's a long term, multi-stage plan... (Score:2)
1) Drop a reactor on Mars
2) Drop a robot tractor on Mars
3) Drop a fuel generator on Mars, use the tractor to pull it to the reactor
4) Drop a greenhouse on Mars, use the tractor to pull it to the reactor
5) Drop a crew habitat on Mars, use the tractor to pull it to the reactor
6) Deliver humans to Mars once steps 1-5 have been done successfully
Hopefully, we'll have some form of nuclear propulsion by the time we're ready for step 6, which would kind of ruin the need for step 3.
For extra coin, you could get spon
Just a note... (Score:2)
SpaceX has specifically said it's Dragon Spacecraft has a heat shield designed to withstand the increased speed that would exist from a return trip from Mars.
"The ablator, called PICA-X for short, was tested inside an arc jet laboratory at NASA's Ames Research Center at Moffett Field, Calif.
"It's actually the most powerful stuff known to man. Dragon is capable of re-entering from a lunar velocity, or even a Mars velocity with the heat shield that it has," Musk said.
http://www.spaceflightnow.com/falcon9/002 [spaceflightnow.com]
Why they don't build a mothership, it's beyond me. (Score:2)
Build a mothership in space, one that cannot land on Earth, equip it with nuclear reactors and a project-orion propulsion system, and then you have affordable space travel to any planet in our solar system.
Then Mars becomes simply a case of having the right vehicle on the mothership.
Re:WTF (Score:4, Interesting)
Huh?
We have ways to get to Mars just fine. An Atlas V 541 is enough to get the massive MSL Curiosity Rover there, and a measly Atlas V 401 is plenty for the Maven orbiter coming after that.
The hard part is getting back. I imagine grabbing resources from the surface and air to create rocket fuel while performing its mission will be the right way to go.
A Mars Sample Return is where the Mars program is headed, and we have a roadmap to get there. And it will force the development of In-Situ Resource Development (ISRU), while will be of huge benefit to all future manned and unmanned programs.
Re: (Score:2)
No the hard part is setting up the equipment to make an easier return trip.
You use one really heavy lift vehicle to send the return rocket to orbit. if you send humans you need to send two or three so you have spares.
Re: (Score:2)
Re: (Score:2)
Err... how many comets?
What's it going to do to Mars' climate - ie will it be a net improvement?
If you're tossing mass at Mars, I'd start by partially emptying the asteroid belt to up it to Earth mass before I started on the Oort cloud for ice, though it might be easier to strip ice from elsewhere.
Anyway, that kind of engineering requires so much more energy than setting up a some large tin cans with self-contained habitats it's not worth it outside a daydream.
Not to mention the fact (Score:2)
That it completely destroys one of the main reasons to go to Mars in the first place - for the science. Oh, you were interested in knowing whether life ever existed on Mars? Sorry, we just resurfaced the planet.
Also, there's the fact that Mars has no magnetic field, whose absence allowed the solar wind to strip the planet of most of its atmosphere in the first place. So unless you want to keep dropping comets on Mars, you'll be back where you started.
And yeah, there's also the energy thing. And the fact tha