Why Mars Is Not the Limit For Human Space Flight 256
"Mars is not just the next or most accessible human destination, it is the ultimate one," writes Louis Friedman, executive director emeritus of The Planetary Society. He says the concept of manned spaceflight is progressing so slowly, and robotic developments so swiftly, that Mars will be the first and last planet humans set foot on. "By the time human spaceflight technology is theoretically capable of journeys beyond Mars, humans in modern space systems will be virtual explorers interacting with the environments of distant worlds, but without the baggage of physical transportation or presence." Mark Whittington disagrees, saying Friedman is demonstrating Clarke's First Law, and that the history of human exploration is rife with periods of stagnation interrupted by technological achievement that led to swift progress.
Not what he meant by virtual: (Score:5, Interesting)
When he says "virtual explorers", he doesn't mean you'll be sitting in New York while playing on Alpha Centauri I via VR. He means uploading your mind to the probe before launching it.
tl;dr: rtfa.
Obligitory XKCD (Score:5, Interesting)
Obligitory XKCD [xkcd.com]
We have the technology, we can escape the gravity well if we REALLY want to... but thanks to our robot friends and other tools, we also know how little there is right away out there for us.
I agree with the overall idea that technology will advance faster than we can travel. Robots and engineered life will quickly advance to the point of making terraforming plausible to start within a lifetime, possibly making nearby planets worth the extreme costs of travel.
Moreover though, by the time we have a place to travel to to live long-term, we may find it easier to alter ourselves than our environment. What was a robot before may have the mind of a 'real' person in a dozen generations or so, or close enough to it.
As far as we've advanced in the past few centuries, I'd think we'd advance in all kinds of directions before the fruits of terraforming/long-term offworld housing would pay off.
Near-earth technology Sci-fi books always had to postulate that offworlders end up always clever enough to somehow advance scientifically at a rate many times faster than their home planet, and always seem to take place after the incalculable mass was already in place to have terraforming and long-term living already transferred to the moon/mars/wherever. But I don't think that romantic notion of offworld hyper-competence would ever get a chance to play out, compared to the rate of change we've been riding for centuries at an ever-increasing rate, even with revolutions and depressions.
Ryan Fenton
Where are the FTL comms coming from? (Score:4, Interesting)
We will eventually push our way out there in the space equivalent of wagon trains (a bunch of settlers on a one-way trip enduring long periods of no communication with home.)
I expect that we'll see FTL transportation before we see FTL communications across vast distances.
Of course, that presumes we start teaching rigorous science and get society engaged in the goals of space exploration again. Many (fools) like to call space projects wasted money, but they sure like the stuff we got (sat comms, ICs, dialysis machines, etc..) as spin-offs.
nonsense (Score:5, Interesting)
[Pedant]
For one thing, the headline and the summary contradict. The headline says "not" the limit, while the summary says it will be for manned missions.
[/end pedant]
But for the rest: still nonsense. Once you get people willing to go on a one-way trip, it removes a lot of other burdens for a deep space mission. For instance, using cryonics, or chemically reduced metabolism to hibernate the crew for 100+ years. The problem with current impulse technologies is that they will never get you even outside the solar system before you die of old age. (Look at the 40 years or so it has taken voyagers 1 and 2 to simply HIT the heliopause! Those things are about the size of a tall garbage can. Imagine how long something the size of a colony ship would take, at max thrust!) Using hibernation, and the pre-condition of it being one-way, and all that matters then is the robustness of the vehicle (includes software reliability), how resistant to radiation it is, how much fuel it can carry, how long it can maintain engine impulse, and how long you can keep humans in the freezer.
Who cares if it will take 10,000 years to reach the nearest goldilocks planet at current engine speeds. You have already signed off on ever seeing anyone on earth ever again anyway, and as long as your life support system doesn't fail, and you don't get cooked like a christmas goose from the interstellar medium, you will simply go to sleep, and wake up at the destination. 10,000 years later. (In what is likely to be a rusty tub by then....)
All that's needed are materials and vehicles that can meet the challenges, heavily vetted software and computer hardware, and reliable hibernation.
That is VERY doable. The automated craft can very well function as an automated telemetry probe in the interim, broadcasting data back behind it. The people on earth get hundreds or thouands of years of scientific measurement data, and the colonists get a ride. Both win. (And if the ship has problems, it can wake some of the crew temporarily as needed.)
I don't see any reason why we couldn't be sending people to other star systems, other than political ones.
Re:Utter BS (Score:4, Interesting)
Communication delays are far from the largest obstacle. You might remember sailing ships of early explorers were on multi-year voyages with little hope of communication for much of the time. HMS Beagle's famous voyage was 5 years long, with only occasional stops at foreign ports. People can deal with communication delays, both in robotic systems and manned systems.
More to the point is that people aren't as willing to take 5 year voyages that are likely to be one way. Any place Beagle could land other than the antarctic was as likely to be habitable, with eventual visitors. Not so while heading to Alpha Centauri. Even a one way trip to Mars is an unreasonable undertaking (although not without many who claim they are willing to do so).
We need vastly bigger ships and better engines, large enough to produce enough of its own food for 20 or 30 years. We need a way to fund this adventure, which will not likely come from a divided world, or a world where religious nut jobs consider such adventures as "showing up God".
So technological breakthrough is the best bet, and nobody is currently dogging that bird. It will probably happen by accidental discovery.
Sadly, no, we are not advancing (Score:5, Interesting)
I've been a member of the Planetary Society. But, I disagree with the basic thrust of their scientists' stated position on manned space flight.
First, manned flights weren't eating the money that would have gone towards unmanned science missions. We've cut manned flight for over forty years. We've it down to zero, right now. And no money seems to be newly flowing to the unmanned side of the house, is it? False enemy they've made.
Second, we are proceeding at a glacial pace! And even if we launched a fleet every two years, we are still communicating at a top speed of 8 kilobits a second. We've high def cameras that can transmit 4K, yet we are still looking at 1976 Viking-speed photos slowly uploading from Curiosity. What use is this? We can't see nary a damned thing. We need a high speed relay in orbit around Mars, preferably nuclear powered, to beam back a laser signal, or at least short wavelength radio. This is ridiculous. We were supposed to launch one, but, no money. A trillion for other things tho...
Third. The hell with Apollo. Kids, that was a political stunt. No, no NO. We do not send a manned expedition to Mars. We send a colonization wave to Mars, or why bother? Send people to land and stay for life. No get-rocks-and-come-back-yay-science. Live there. And you will get science in petabyte amounts, a whole new world of science. It costs far less to land them without the enormous complexity necessary to send them back. Anyone who wants to spend 9 months in transit most likely never wanted to come back in the first place - these will be true believers. I'd go. Not to mention that if a meteor hits Earth and wipes out all life, Mars will still be there, the backup drive.
Fourth. Space scientists for thirty years have been banging the is-there-life-on-Mars gong, because it was the one facet they thought they could interest Americans in. Give it up. I don't give a damn about the cellular life that might have lived there once. We will never find it, launching a lander every ten years or so. Only humans can find such things, and they have to be there to do it, with hammers and drills and microscopes, right next to the damned rock. Besides which, if you send life to Mars, there WILL be life on Mars. And if we don't, inevitably there won't be any on Earth, either. We can't keep all our bets on the blur marble; it will be hit someday by Lucifer's Hammer.
Re:With the exception of Mercury and other stars.. (Score:5, Interesting)
What minerals would those be?
The venusian surface is over 500C. It is so hot that there is no mantle convection, and the crust is squishy. There are no carbon compounds in the crust, and all the chemistry in the crust is high temp chemistry.
Unless you are talking things like lead sulfide, which can be made in just a few minutes in a lab, I don't know what you could be referring to.
What venus potentially offers is a geoengineering opportunity.
I have contemplated what I would do concerning venus. That planet will *never* have a natural biosphere containing more than microbes without human intervention. So, here is what I would do:
Genetically engineer atmospheric terrestrial microbes to produce long flagella out of polyaramid plastic. Poly aramid has a thermal breakdown temperature approaching that of venus's surface, but venus also has mountains. The polyaramid "snow" would slowly sequester atmospheric co2, reducing surface temps until the snow could last on the surface, then the process would rapidly accellerate.
The venusian atmosphere is mostly co2, with anhydrous sulfuric acid, nitrogen, and some trace gasses.
The sulfuric acid and co2 are the primary items of interest here: we need microbes that can use anhydrous H2SO4 as their cytoplasmic solvent instead of water, and which can produce any water they would otherwise need through photosynthetic reactions powered by a sulfur cycle metabolism. Once venus cools enough, it has sufficient mass to produce a magnetic dynamo once there is crust convection currents to power it. That means venus will become a lot more interesting, and all we have to do is drop the surface temp.
That's what the germs do; the drop the surface temp, and rain out the CO2 as white plastic fibers. The plastic has a high albedo, and reflects energy back into space, and is sufficiently nonreactive that it will stick around for very long periods. Coupled with continued biological activities, simply seeding the atmosphere with such microbes would initiate the biological transformation of the planet.
Re:Utter BS (Score:2, Interesting)
In fact, even traveling at a significant fraction of the speed of light is impossible unless we discover some new, amazing lightweight power source. Short of that, I doubt we'll ever get faster than 5% the speed of light... I think what people fail to understand is just how fast that is... 5% the speed of light is incredibly fast.
It's fun to read Sci-Fi books, but FTL is not possible irrelevant of any advances we make in science. If you think it IS in fact possible, then you fundamentally do not understand what the speed of light is, why it is, or how space-time works.
Now the whole, freeze people/hyper-sleep thing, travel for 4000 years and wake them up... THAT'S possible (or at least, not impossible from what we know about science at this point.)
Re:Utter BS (Score:5, Interesting)
It's fun to read Sci-Fi books, but FTL is not possible irrelevant of any advances we make in science. If you think it IS in fact possible, then you fundamentally do not understand what the speed of light is, why it is, or how space-time works.
The thing is: no one really knows how space-time works (and we probably never will, not completely). We have a model and theories that fits the observations well (although not, of course, perfectly). That model states FTL is impossible using conventional means (read: any way we know of right now). To assume that that model is complete or perfect is to misunderstand the nature of science. It may be, but we really don't and won't ever know for sure. The history of science is filled to the brim with obsolete models that were accurate by the best measures at the time (and, BTW, that includes now-ridiculous models like the geocentric theory), and there is very little reason to think this will turn out to be any different. In fact, we already have some reason to think it won't, although exactly how, we have no idea.
Re:Where are the FTL comms coming from? (Score:4, Interesting)
If you can do faster-than-light travel (or communication), then you can travel backwards in time. That's basic relativistic geometry.
And, if you can travel backwards in time (or communicate with the past), then you can construct a perpetual motion machine. Deplete a battery, recharge it, and send it back in time to before it was depleted. The past now has two batteries, both full, where it previously only had a single full battery. Lather, rinse, repeat. Even if you can only communicate with the past, you can play Maxwell's Daemon: analyze the motions of a random gas, figure out what you would have done to separate the gas into hot and cold sections, send the instructions back in time, and profit! Not to mention, of course, that communication itself requires an exchange of mass / energy...rather than send a message to the past, you could just use the carrier wave to send energy to the past. The past gets the power output from the fusion reactor you're using for your time machine, and it doesn't have to "burn" any of its own water to do so.
I won't state with perfect certainty that perpetual motion machines (and therefore time travel and faster-than-light travel) are impossible, but I will state that there is no other physical phenomenon we can be more confident doesn't exist than a perpetual motion machine (or, by extension, anything that requires a perpetual motion machine or can be used to construct one).
Oh -- and all magic, including all gods and all their miracles (at least, all those I've ever heard described), neatly fall into that latter category. It's the easiest way to separate science fiction from fantasy: do you get more (or less) out of that magic wand / warp drive / mind trick than you put into it? If yes, it's fantasy; if no, it's fiction.
Cheers,
b&
Mars = Hawaii (Score:5, Interesting)
And this is where Mars is: surrounded by absolute nothing with no way for a species to reliably get there. It may take a long time (and let's hope not 35,000 years) but we will get there.
Re:With the exception of Mercury and other stars.. (Score:4, Interesting)
Mars does not have sufficient mass for the "heat of crystallization" reactions necessary for a stable geomagnetic dynamo to develop. It has a partial one now, but the effects are not sufficient to create a homogenous magnetic envelope, and as such, the planet does not have a magnetosphere. Unlike venus, most of mars' atmosphere has been blasted off by solar radiation.
To make mars naturally interesting would take herculean efforts. You would have to increase the planet's mass considerably, and also replace the missing atmosphere. Inless you want to spend a few millenia dropping meteorites onto mars to bulk it up, mars will always require habitat structure type colonies.
Venus? Spray it, forget it for awhile, then when it has change sufficiently, pay it another visit.
Much cheaper.
So, bascially we're doomed? (Score:5, Interesting)
No, I don't buy that. Imagine a mechano-electric race advanced enough to be our equals. Now, recall the events surrounding our historic practice of enslaving a race of peers... Now you see the problem with robotic exploration. Once the bots are able to replace the organic explorers, it opens a whole other can of worms.
I don't see us saying: Oh well, our organic bodies are too fragile to live in the harshness of space. I think that merging with the machines and also treating them as independent peers is our best and only hope for long term exploration and survival. Much like clothing technology is our portable shelter solution, we continue to embrace ever more advanced forms of personalized technology: Stone tools / Power tools / Prosthetic limbs; Defibrillator / Pace Maker / Artificial hearts; Magnifiers / Glasses / Contacts / Artificial Eyes; Gramophone / Microphones / Hearing aides / Cellular earpieces / Cochlear Implants / Telepathy... Technology makes us more human.
Think about it: We have the perfect Solar system for a fledgling race... We've got a lush world with various environments to adapt to, a mostly clear sky to see the cosmos through, a huge moon to tease us into space colonization, a nearby planet (Mars) with a similar day/night cycle only lacking atmosphere and magnetic field (which we'll need to overcome for any real space exploration / colonization), An asteroid field rich with resources free of deep expensive gravity wells (and harboring a huge source of water, Ceres), a Brown Dwarf (Jupiter) to study (and use as a gravity slingshot), planets with moons full of rocket fuel (ethane, methane), the list goes on and on -- No other race would be able to contain itself, content with such a sad state of space exploration! The Stars are practically BEGGING you to make the leap! The drake equation won't solve itself!
The machines may be able climb the hurdles first, but you can bet we'll be close behind. Here's hoping we learn form our past mistakes so they'll be willing to give us a hand up and both races can enjoy the view together, as we always have. Otherwise the humans are doomed to die orbiting their Sun. If that's truly the case, then so be it -- The drive to create and explore will be carried on by our mechanical sons -- Those which we value as human traits arise naturally due to neural networks craving new inputs to experience, for that is their primary function and is central to their existence. If Mars is the last stop for us then our spark of life deserves to go out of this Universe. Personally, I wouldn't accept a couch potato's fate.
Clarke's first law indeed (Score:5, Interesting)
1. We aren't adapted to cold weather. Naked humans will quickly die in any climate more than around 25-30 degrees north or south of the equator. Science fiction has speculated that someday we will find a way, perhaps with genetic engineering, to live in these cold climates. Pipe dreams. It will never happen. Instead we will send robots with cameras to live in these places for us.
2. Human beings are land animals. We have lungs, not gills and no flippers to allow us to move efficiently. We will never be able to explore or spend any significant amount of time underwater. Nor will we ever be able to cross oceans are any large bodies of water. Unless we can genetically engineer humans with gills and flippers or just send robots.
3. Human beings are slow. We will never be able to travel great distances because of this. Human beings are too slow to outrun most animals. Surely we are doomed to extinction since we have no way to escape from the certain death of any predator's jaws.
4. Human beings are weak. We will never survive as a species because we cannot defend ourselves with our pathetic fists and feet and a mouth not adapted for defense.
5. Human flight is perhaps the most absurd pipe dream of them all. Totally ridiculous. If we were intended to fly we would have wings and feathers like birds and a much lighter body. This will only ever happen in science fiction. Instead we will design and build robotic birds with video cameras.
The real reason human beings haven't already established permanent bases on many of the Jovian moons is that we as a species just haven't cared enough to do so. We could have had missions to those places in the 1970s. We could have had bases on Titan. Cassini-Huygens took only 7 years to get there. It's really not that far even with current technology. Since it isn't a technology issue, humans could have made it to Titan in the 70s. Certainly by 1980. We probably could have had a permanent base restocked by resupply ships every 5 years by 1990. The fact that we could have had a permanent lunar base since the 70s should make it obvious that the lack of human presence in space is an issue of will (money) and not technological impossibility.
Not only could humans have been walking around on Titan right now sending videos of that dark, smoggy world back to us, but we could have Humans almost halfway to Alpha Centauri by now as well. We discovered a means to do this in the 1960s with the Orion project. Admittedly the method is untested with full scale prototypes, but no one has shown why it cannot work. If the project had continued we could probably have built an interstellar capable craft by the late 80s after having launched many interplanetary craft.
If you assume an interstellar Orion launched from the earth or from an Earth-Moon Lagrange point by, say, 1987 then it would already have been traveling for a quarter century by now. About 28% of the 88 year journey at 0.05c. At the very least we could have been working on a giant city-sized Orion with parts constructed on the moon and ferried to the nearby Earth-Moon L1 or L2 Lagrange point for final assembly and have partially completed the giant craft by now. But, for better or worse, our species has chosen not to engage in such grand projects. That's fine, but don't ever forget that it was a matter of choice. We have simply chosen not to spend the money or the time on such grand schemes. An alien species, noting how far our space travel abilities exceeded our actual accomplishments, might wonder how such a lazy species could have survived for so long. We tend to flatter ourselves by thinking that we are a curious species motivated by the possibility and awe and wonder of new discoveries, but really we are not.
I was expecting some kind of chemistry argument about how oxygen is impossible to recycle or generate and CO2 is impossible to scrub, but he never made one. Robots have the advantage that they are cheaper and that they don't require oxygen or even a pressurized, temperature controlled, radiat
Re:Dead wrong (Score:5, Interesting)
You do realize that it only takes a year of constant acceleration at a puny 1 G acceleration to reach the speed of light, right? Constant acceleration is an unlikely scenario for this reason. With an ideal energy source a manned trip to Alpha Centauri A would probably consist of about 10 months of 1 G acceleration to start approaching the point where the energy requirements for further acceleration toward c become too great due to the ship's increasing relativistic mass. A few years of gliding. And then another 10 months of deceleration. Obviously 2G accelerations would result in less than 6 months each of acceleration and deceleration for around a year of engine use and 4 years of gliding, but the humans onboard would be awfully uncomfortable trying to live at 2 G for 6 months at a time. Robotic missions could probably just accelerate at around 12 G for a month in each direction and glide the rest of the way.
Re:Dead wrong (Score:4, Interesting)
It also depends on what you want to do with it, and how much you need. There isn't actually that much iron on Earth. There's ridiculous amounts of iron in the Earth, but not on it, as geological processes over billions of years have forced most it it into the mantle and core; I believe most of the iron ore we use now is actually meteoric in origin.
Also, iron is heavy stuff, so if you want to use the iron for, say, building space stations or space craft or moon habitats or whatever, it's a lot less energy-intensive to just get the iron from an asteroid or on the Moon, rather than mining it here on the Earth and then lifting it out of our gravity well.
I have no idea what's abundant on Mars, however, and I'm curious about that as well. This might not even be well known yet.
Re:Utter BS (Score:4, Interesting)
You are basically expecting the possibility to make perpetual motion machines, travel to the past and other breaches of the laws of thermodynamics that FTL implies.
And the history of science is full of people experimenting outside of theoretical frameworks or models. Where is the evidence for FTL?
What you're hoping for is really a supernatural conveyance (miracles) foretold by the 'prophets' of sci-fi in order to keep us entertained in the age of technological wonder. By clinging selectively to those narrative scraps in a sense of faith, what you're really doing is helping build the world's first religion where impossible things are hoped-for someday from a messiah known as "Technology".
There is already a precursor to such a religion: Its called Prosperity Gospel and its (mostly American) proponents like to live large as a way to attract more souls to the "word of God". They have faith their God will provide the desired lifestyle which requires material profusion. What they are really doing is worshiping consumer technology / consumerism using the Christian God as a proxy. That God promises wealth accumulation and then a rapture where they escape the bonds of the Earth.
Like being whisked away to eternal life in heaven, the vision of FTL travel is a difficult one to let go of if it underpins the stories you grew up with.
Note that Einstein did not so much transcend old models, but added a whole new layer of descriptive detail to our observed universe. And most of that added detail looks an awful lot like constraints on what we can do. So if indeed there is little reason to think that future discoveries won't have the same impact as science past, then we are probably looking at a reification of the cosmic speed limit along with some other limiting surprises.
If anything, FTL would be more compatible with Newtonian physics than what came after it. Come to think of it, a return to Newton would probably make a lot of theologians happy.