New Mars Forums

quote:

"Musk seems to have several things going for him: (1) a team of dedicated young engineers who want to succeed; (2) the luxury of looking at the big picture and figuring out the cheapest, easiest way to do it, without lobbyists asking to fund their special big rocket or Congressmen insisting on expenditures in their district. Musk also seems to have good instincts about what near-term technological innovations to pursue and which need to wait."

There you went and put your finger squarely on what is wrong with NASA,  and what will eventually afflict ESA,  JAXA,  and all the rest:  a government program in which tactical details (not just overall strategy) are political footballs.  This went wrong for NASA in the 1970's,  and they have accomplished no significant large exploration objectives since.  The ones they have accomplished have all been robotic,  and all have been the subject of drastic political fighting in Congress. 

Let that be a lesson to all my non-US correspondent friends. 

If anyone can break this deadlock,  it will be Musk.  But I have my doubts he can single-handedly pull off a manned Mars mission that really leads anywhere.  That's because he only has the resources to fly there maybe once or twice.  And,  (here's the real problem) the "exploration" isn't yet done.  There is a capstone exploration mission with men that you simply cannot do with minimalist mission designs.  You do not need "Battlestar Galactica",  but you cannot do it with one Dragon full of 1-6 men,  either. 

The key is limiting your government legislatures to ONLY strategic objectives.  Forbid them EXPLICITLY from dictating tactical details.  It is likely way too late for the US & NASA,  but ESA and JAXA might still stand some chance if this is done.

This is important because most corporations DO NOT function like Musk's Spacex:  they will not invest in anything unless there is demonstrable short-term profit.  Mars will not show profit for a long time yet.  (Sorry,  but it it just won't.  To expect otherwise is simply not realistic.)  Neither did the Roanoke colony.  Even Jamestown was a financial loss for a long time.

You have to focus on what government can do best and on what corporations can do do best.  There's less overlap than most folks believe.  The "smarts" lie within the corporations,  not the government labs.  But corporations only do speculative things if a government will pay them to do it.  Chicken-and-egg......

Once you get by that conceptual hurdle,  you can design practical missions to the moon,  Mars,  NEO's,  even to the stars. 

But NOT until you take that hurdle into account.  Sorry.

That's about 500 years of our history talking,  not me.

GW

louis wrote:

Paper is only so-so as a permanent storage medium. It can be damaged by insects, water, fire and numerous other occurences.

Friendly ribbing: You obviously don't work in the data-preservation industry, heehee!

At the moment, despite all precautions, and rah rah, digital is still *very* finicky for long term storage. You have to *actively* keep it 'fresh' or stuff gets unreadable in less than a decade.

On the other hand, I regularly work with paper documents that are hundreds years old, and nearly pristine, and no-one had to do a thing to keep them that way. Store dry and cool.
That's all.

Paper has one big advantage: it's 'human-readable' no machines needed. No software needed.

NASA has tapes it can't read back, they're barely 3 or four decades old. The tapes are okay. No-one builds the spare parts of the readers, so they have a problem.

The toilet part on the other hand is spot on, paper is soooo 19th c tech.

OK, now I get to become public enemy #1.

Bamboo OK, fine, the pressurized gardens would be satisfying.  The wood good.  A sponge on a stick, ICK!

Have you considered Alergies?  Runny noses. Well what if?  What if a disease developes or is imported.  And for clean up, paper products are valuable.  And paper itself is not indespensible.  Our paperless office where I write software for, is hardly so.  I guess if you had to.  But why limit yourselves.

I propose paper from Algae.  Algae has no reason to manufacture cellulose, but could a type be created that would do so?

Pick one that is happy on cold brine like arctic sea water, one that likes about the solar flux that would exist in a greenhouse on Mars.

Make a nominally unpressurized greenhouse with a pool of cold brine in it.  Maybe -2 degrees C or colder, up to the coldest temperature where that algae could be productive to it's maximum.

The point would be to generate Oxygen to be collected from the Greenhouse and Cellulose.  From that paper, and fake wood as well.  And the dried product could also be a fuel in a pinch, perhaps easily stored outside with minimal protection.  Not a prefered fuel, just an option.

I know how responses occur here,  bamboo is fine, but if this other thing could occur why not that as well.

http://www.lewisbamboo.com/cold-hardy-bamboo.html

http://www.bamboogrove.com/bamboo-paper.html

http://www.google.com/search?q=paper+fr … d=0CHAQsAQ

It would be nice if it was even more cold tollerant, but I am sure a greenhouse which limits it's coldest climate to that of an Iowa winter is possible on Mars.

I have always wondered how people would be able to maintain hygene on Mars without sanitary paper, such as kleenex, paper towel, and so on. And I don't think people who fly space ships would want to be doing the right hand left hand thing.

Paper from bamboo.

I also mention bamboo or other plants as evaporators.  Water with grey or even worse water, and then let them eveporate more or less clean vapors into the greenhouse air, and then condense reasonably clean water using the Martian cold nights.

Obviously this is a case where Mars is way ahead of the Moon as a place to do it.  So, less reason to divert to the Moon.

No, none of the landings had access to any ground signals. You are right, that would allow steering and much more precise landing, without much more delta-v.

I have never seen the Delta Clipper clip before, but had heard about the precise landings and the unfortunate end of the program. The Falcon X and the Dragon are supposed to do the same thing.

I am intrigued by your approach, Louis, and I think you are right: the era of private space exploration may be at hand, and it will be conducted under different rules, more practical and more economic. Government space exploration has been oriented around science and, franky, political concerns like creating jobs.

But even so, there's no reason to spend $500 million to send an extra 150 tonnes of propellant to Mars to avoid using a heat shield and parachute. They are well developed technologies, we know what materials to use on Mars (we've used how many heat shields and parachutes there?), and they aren't expensive to develop and build. Maybe he retrorocket technology is expensive, since it appears that's an issue. But we don't know that for sure, and neither of us are technical experts.

I am also rather concerned about very small landers for human crews. The first crew needs to bring with it the stuff it needs if it misses the landing site; otherwise, they're dead. The exception is if we've already landed a dozen or so vehicles of similar size on Mars and they've all come down exactly where they are supposed to.

I am also uncertain how easy it'll be to build up a large unmanned base with robots and such before we send humans. So much can go wrong that a person with a screwdriver can fix, we may need people there early on. If we need people there early on--which will also make the mission more attractive to the public--then we need to be sure to land enough stuff with them to guarantee their survival. You don't want them to land 500 km from stuff, have no way to get to it, and starve to death slowly on CNN. Your company wouldn't survive, nor would a government Mars program. That's not a question of engineering, but of emotions. And the exploration of Mars is an emotional topic at its heart; otherwise we'd all be saying, let's go back to the moon.

One can launch to Mars, as you know, only once every 26 months, during a window that lasts a few months. The normal time to launch back to Earth from Mars is before anyone can get to Mars from Earth. The exception is if you have a lot of fuel.

We won't have a lot of fuel during the first mission, either. Possibly some people can stay two cycles, but I doubt that would normally be part of mission 1. So Mars probably will be abandoned for about 9 months, at first (except in the novel I wrote).

But I don't think that equates to flags and footprints. Next time we return to the moon it will be an "Antarctic commitment"; in other words, there's no obvious commercial, political, or military advantage, but many nations nevertheless have made a long-term funding commitment to the scientific exploration of Antarctica. Falcon Heavy may made such a commitment financially practical for the moon and I hope for Mars as well. With Falcon Heavy, you can send six people to Mars every two years for less than a billion dollars in launch costs. Once the equipment is developed, it can probably be had for a similar amount as well. A consortium of several nations can easily make such a long term commitment.

Such a commitment needs to be build into the initial plans. In fact it has to be, because the humans will probably fly during the third launch opportunity. You need at least two earlier launch windows to do the preparation. So I'm not too worried about a commitment to at least a half dozen missions. After that, perhaps, there will be questions about what direction to take. We can't predict Martian development beyond the first few missions very well because we don't know the unknowns. If they find evidence of past life, that will be immensely important because Mars possesses vast amounts of rocks that date from the precellular period. It may tell us how life went from organic soup to cellular life, and that's very important. Perhaps we will learn how RNA came into existence and then evolved into DNA. It will also tell us a lot about climate change. So it's a gigantic "Antarctica" of huge scientific potential. People will win Nobel prizes in biology and physics from their research on Mars.

As for manufacturing infrastructure, I doubt it can be set up in a few days. Not much manufacturing equipment is designed for sub-Antarctic temperature conditions, for example. It will take a lot of money and experimentation to develop effective equipment that operates under Martian conditions. Just obtaining water will take time, until we figure out exactly what works well and easily. It may be that the first expedition will take a year or two to figure out how to drill a water well and extract water, but 30 years later, a half million dollars of equipment will allow someone to homestead almost anywhere on Mars (because if you have water and sunshine, you have just about everything you need, and there's probably water everywhere if you drill down far enough).

If we're talking about using aerobraking to go into Mars orbit after a Hohmann trajectory or a six month trajectory, there's no problem. Mars has plenty of air for that and it has been used many times for incremental aerobraking (lowering the apoapsis of an orbit).

But if you are going faster than that--a 4 or 5 month transit between planets, for example--you hit the atmosphere much faster, which also means you transit through it in less time. Regular heat shields are too small for that. Big extra-wide ones will help and ballutes (which are still a theoretical idea) will help. Either way, one is talking about rather high gee forces. We may develop technology that can reliably use the Martian atmosphere, though.

Landing is a third problem because, according to the article I read recently, the atmosphere can't slow a large vehicle below about Mach 2 or 2.5 before the Martian surface gets in the way. Heat shields would have to be much larger. Parachutes can't work in speeds over Mach 2 or 2.5, either; they're shredded. If you open a parachute at Mach 2, it has to be 100+ meters in diameter, which may not be practical. And rocket engines have difficulty working when flying into the "thicker" air near the surface at such high speeds. Perhaps canted engines that fire at 45 degrees will work.

It's hard to appreciate this problem without personal experience. In July 1976 I was in the science control room of Viking 1 as it fired its engines and headed for the surface. It was rather frightening; the thing fell like a rock. All we could look at was a simple, small black and white tv screen that showed Viking's altitude in feet and velocity in feet per second. Maybe there was other data, but I don't remember what. Whenever you did the division, it always seemed like it was going to impact in less than 30 seconds. Of course, at first Viking was mostly moving forward, not downward, so the numbers were a bit deceiving. But if I recall, the whole operation took less than 5 minutes. When you fire the deorbit burn in low Mars orbit, you go down, and fast!

We have an individual on the Facebook page who is arguing for the full 90 Day Report. He claims we have to build a permanent Moon base before we can go to Mars. He want everything. For those who are new to the Mars Society, let me give a little history of where we came from...

Back in 1989, then president George Bush Sr. stood on the steps of the Air and Space Museum and proclaimed "We will go to Mars!" NASA trundled off and 90 days later  came back with a report called the "90 Day Report". It called for a space station, Moon base, fuel depot in Earth orbit, a second space station to check out the Mars spacecraft, and a giant space craft for Mars with onboard greenhouse and nuclear engines. Well, I like nuclear engines, but this craft was WAY too big, it looked like something from Hollywood. It would take 26 months round trip (dictated by planetary orbits) but they would only land half the crew on Mars, and they would only spend 2 weeks on Mars before heading home. The price for all this was $450 Billion! Congress took one look at the price tag and immediately killed it.

At that time Dr. Robert Zubrin worked for Martin Marietta, that was before they merged with Lockheed to form Lockheed-Martin. Dr. Zubrin and another engineer designed Mars Direct. The premise was to do it like Apollo: go to Mars, go directly to Mars, do not collect $200. The reference to the board game "Monopoly" is on purpose. Military contractors have been gouging NASA every since the Space Shuttle.

After years of lobbying, Dr. Zubrin convinced NASA that the plan by himself and his partner was a good one. NASA accepted it, but changed it. They expanded the crew from 4 to 6, and insisted on bring fuel for the return to Earth all the way from Earth. One of the key features of Mars Direct was In-Situ Propellant Production (ISPP). That means making fuel from stuff you find on Mars. That wasn't a new concept, NASA had looked at converting CO2 from Mars atmosphere into CO and oxygen. The problem was carbon monoxide is a REALLY bad fuel. Dr. Zubrin came up with the idea of bringing a little hydrogen from Earth, and using technology from the 1800s to produce methane and water. Run water through electrolysis, recycle the hydrogen and store the oxygen. Methane/oxygen is a really good fuel. But NASA's modified plan, which Dr. Zubrin called Mars Semi-Direct, was more than twice as expensive. NASA budget guys came up with a cost estimate for Dr. Zubrin's Mars Direct: $20 billion for the first mission, plus $2 billion for each mission there after. Or $30 billion for 7 missions if NASA commits up-front to that many. (Buy 6 missions, get one free!) Since planetary orbits dictate each mission can only happen every 26 months, that means once start-up costs are paid, a Mars program would cost about $1 billion per year. But NASA's Semi-Direct would cost $55 billion for the same number of missions. NASA looked at this and said "You haven't even built anything and the cost has already more than doubled! I know you guys, if we approve anything you will insist on everything in he 90 Day Report, with its price tag of $450 billion." So they refused to approve anything for Mars.

Now we have someone on Facebook saying we need everything from the 90 Day Report. This is exactly what congress has been afraid of these last two decades. With the Shuttle now cancelled, NASA has enough money for ISS operations, unmanned space exploration, and a human mission to Mars. They don't need anything more. Specifically, if they cancel the Liberty Rocket (formerly known as Ares 1) and the Multi-Purpose Crew Vehicle (MPCV, formerly known as Orion) they will have enough money for Mars. American will still have the Dragon spacecraft by SpaceX, and DreamChaser by Sierra Nevada Corporation, so 2 vehicles to carry astronauts to ISS. They don't need MPCV as well. What we do need is a dedicated Mars spacecraft, and MPCV doesn't cut it. And the Space Launch System (SLS, the original design for Ares V) is currently funded; we need that big rocket to go to Mars.

Congress has already said the reason they won't approve any funding for a human mission to Mars is because they won't fund what's in the 90 Day Report. Continuing to demand everything in that report will only ensure Congress never approves human spaceflight beyond ISS. So this guy on Facebook gets me angry. He claims to be pro-space, but what he's doing will ensure Congress will never approve anything.

Lets take the above principle further. That is you take no compromises with the human cargo but take your engineering risks with everything else.

What that would mean for instance is designing a mission that gets the humans there faster, but use the slow lane for for everything else. Now that's not strictly about landing but it does affect how you land. And I also know that this has been said before its surprising how many missions choose slower routes because of the need to ship the humans inside the hab.

What I have in mind here is that there's been a lot of talk about using aerobraking into a Mars orbit.

For me that's a good way to save on fuel mass for things like your hab, your ISRU, or an orbiter.

But I've never been terribly happy with missions that propose to fly the humans along with all that, and then take the risk of aerobraking.

Also, for the non-human side of the landing this is where a large in earth orbit heat shield comes in handy since it can serve a dual role for both aerobraking and then landing.

One last idea I'd like to run past the experts. What if, instead of things like ballutes or large shields, or some combination thereof, what you're actually building is basically a deep sea anchor. Its something you design to create a lot of drag but it projects hundreds of metres or more into the slipstream of the craft. It could be based on cables, or it could even have a backbone. Onto that you could attach semi right structures that are designed to create drag, or even inflatable drag structures. The point being is the whole design is inherently stable.

Any thoughts?

Self sufficiency is also a function of transportation costs. If Musk can develop reusable Falcons and can transport stuff to Mars for hundreds of dollars per pound, then it is practical to export Mars rocks for those who want to buy them, argon and nitrogen for use on the moon, gold if very rich deposits can be found, etc. If the cost is closer to $100,000 per pound (which is what it would have been with the Space Shuttle, for example) then self sufficiency is impossible and long-term expansion is virtually impossible.