Time to Go Says Hawking

I'll second that emotion......  it's one of the best blogs I've ever read, and I point people to it ALL THE TIME.  His "energy trap" post is a classic.

Oh, and Hawking's lost it IMHO...  you'd think he'd know better!

Mike

Hawking is brilliant but he's also a bit of a savant and wrong about some of the most important things.  I'm sure he thinks this beauty is just a random biological occurrence.

http://player.vimeo.com/video/27920977?title=0&%3bbyline=0&%3bportrait=0href

What gets me every time this idiot talk of moving to the stars comes out is that for anyone to do it, they would need to live hyper sustainably, recycling EVERYTHING, food, air, waste, energy...... and of course you can forget multiplying on a small space ship too!  Yet NOBODY's talking about the fact that if we did this right here on Earth, well we wouldn't need to go anywhere now would we!

Mike

I think some of you may be reading a little more into Hawking's statement than is really there.  From the article it didn't seem like Hawking was presenting space travel as a solution to our energy or resource problems here, but rather as insurance against human extinction or indefinite collapse of technological human civilization in a era of increasing societal volatility.  Diversification in a time of great uncertainty, as it were.  That seems prudent does it not?

I concur with Land2341.  Space science & exploration is not going to cure our problems down here, and we can't and shouldn't count on a space-based Hail Mary pass that fixes our problems on Earth or as a way of running away from the problems here.  But neither of those was ever the point behind space exploration, were they?  It's about expanding the frontiers of human knowledge and experience.  Sure there are ways space resources and technologies can provide us with benefits down here, but those were really secondary reasons that were overshadowed by the urge to explore and expand our boundaries.  What Prof. Murphy said in his article is that space is not a cure or solution for our energy and resource problems down here, and that expanding space exploration and colonization is much more difficult than most people assume.  And I wholeheartedly agree.  But that is not the same as saying that manned space exploration, travel, and colonization (at least within our solar system) is infeasible, or that the attempts should not be made.  Prof. Murphy's article is a great moderating counter-balance to excessively enthusiastic pie-in-the-sky assumptions about space exploration, but not an argument of its futility. 

The sad thing is that I think if we played our cards right, we could continue to have and make progress in space exploration in a "world of less", and I would argue that we should.  But most nations are doing the wrong things, increasing the chances of such great global upheaval that space eventually falls out of our collective reach.  Our scientific and engineering ability is there, but many of our societial priorities are f***ed.  It's like watching a scientific or artistic prodigy killing himself with drugs; the ability was there, but all for naught because of bad decisions. 

What gets me every time this idiot talk of moving to the stars comes out is that for anyone to do it, they would need to live hyper sustainably, recycling EVERYTHING, food, air, waste, energy...... and of course you can forget multiplying on a small space ship too!  Yet NOBODY's talking about the fact that if we did this right here on Earth, well we wouldn't need to go anywhere now would we!

Mike

DTM/Rihter-

You guys are actually making a good argument for trying such a thing.  I know I've said this before, but how better to increase awareness of resource limits and utilization than to live in an environment where bad decision-making and poor impulse control leads to immediate and sometimes severe consequences?  It's in adverse conditions where we see human beings either step up, or step aside.  So on the contrary, it may be quite possible a smaller group can do what the larger group does not.... not because they're smarter or 'better', but simply because they're put in a drastically different environment that constantly forces them to re-evaluate their priorities and be more aware of the consequences of their actions.  We don't see that kind of self-aware behavior down here so much because we don't have that forcing pressure.

Yet. 

(cue ominous music... Bum Bum BUUMMM!) 

- Nickbert

There's nothing wrong with dreaming as long as you keep one foot in reality....

Kiss space goodbye : Pharyngula

Charlie Stross examines the economics and physics of colonizing other planets, and he isn't at all optimistic. Forget going to planets around other stars — the distances are absurdly excessive. But also forget about colonizing planets in our solar system: not only is it ridiculously expensive just to put a human being on another planet, it isn't even an attractive proposition.

When we look at the rest of the solar system, the picture is even bleaker. Mars is ... well, the phrase "tourist resort" springs to mind, and is promptly filed in the same corner as "Gobi desert". As Bruce Sterling has put it: "I'll believe in people settling Mars at about the same time I see people settling the Gobi Desert. The Gobi Desert is about a thousand times as hospitable as Mars and five hundred times cheaper and easier to reach. Nobody ever writes "Gobi Desert Opera" because, well, it's just kind of plonkingly obvious that there's no good reason to go there and live. It's ugly, it's inhospitable and there's no way to make it pay. Mars is just the same, really. We just romanticize it because it's so hard to reach." In other words, going there to explore is fine and dandy -- our robots are all over it already. But as a desirable residential neighbourhood it has some shortcomings, starting with the slight lack of breathable air and the sub-Antarctic nighttime temperatures and the Mach 0.5 dust storms, and working down from there.

Sterling is being optimistic there — no way is it only 500 times more expensive to go to Mars rather than the Gobi.

I love to read space opera, but face it, it's about as realistic as your goofiest high fantasy novel with elves and gnomes and magic swords. It's not going to happen, ever, but it is still fun to dream.

Safewite said it best here:

As our resident science fiction writer/editor (my magazine Abyss & Apex is here; the book I edited with our Best-Of is here), allow me to chime in on the whole terraforming and leaving earth subject.

Those of you who are not aware of the amount of energy it takes to break out of earth's gravity, please take note. Here is a rather succinct explanation.  Long story short? It takes a lot of energy, as does the whole manufacturing process to make what you are bringing up out of the gravity well (the space ship and "stores" to bring with you.) Distance to Mars, the only viable candidate in our solar system, is ...prohibitive, as are conditions there. Distances to other star systems, where we might be able to infer a Jupiter-sized planet (with no guarantee of any world in the habitable zone) by the perturbations of a star's gravity are...well, there is a reason that we use the term "astronomical." It might take several generations to get there, where ever there might be. And then our descendants, if they  even make it there, may not find a usable world.

So, leaving earth as a mass migration or even as a select few, and then terraforming (another subject, and you really do not want to go there) that world? Ain't gonna happen; it's not only impossible for cash-strapped debt-ridden governments but peak oil mitigates against it on a global scale. There's a reason science fiction is labeled "speculative" - most of it cannot happen in real life. We are very much stuck on this planet with the one world we have. Our world is not disposable; neither is it replaceable.

I find it hard to believe that any rational person who has really paid attention to CM's crash course, let alone the myriad of other energy studies available, would even entertain the idea that humankind is going to colonize other planets, considering the vast distance to be traveled, the harshness of those barren alien worlds, as well as the outrageous amount of cheap energy required to get there and maintain such space colonies. But such people are, I suppose, in good company because the subject of this post, Hawking, believes its our only chance for survival:

"Life on Earth is at the ever-increasing risk of being wiped out by a disaster such as sudden global warming, nuclear war, a genetically engineered virus or other dangers ... I think the human race has no future if it doesn't go into space."

I think Hawkings is right in his assessment of the precarious future the human race has dug for itself, but he's unrealistic in what it should do to save itself. Facing up to the self-created problems in the here and now on planet Earth before even dreaming of seeding outerspace with our kind would seem to be a mandatory rule. Nevertheless, we'll entertain the idea of space colonization despite the crushing weight of civilization-collapsing factors occurring here on Earth.

Since there are no hospitable planets within our solar system, we would need to be able to travel interstellarly. The stars visible from Earth are 50 to 100 light years from us, our galaxy being 100,000 light years across. What kind of energy would fuel such travel? How would you sustain the humans on such ships at such great distances over such long time spans? The astronauts would likely be dead of old age before they reached any habitable destination. Do you see how silly and incomprehensible such ideas are? Barring the discovery of some new form of free energy, along with resolving other seemingly impossible barriers, space colonization is just a fantasy of sci-fi stories.

I know a few peope who have been in space for years as well. And I know what there secret is. It involves controlled substances.

Is it?  I remember once reading that every time the shuttle takes off, it uses as much energy as all the cars in LA consume in one year.....  and that's just to get into ORBIT!  Never mind going to Mars or another star......

Yes, it's ridiculous alright, and the question stands.

Mike

xraymike-

Please do tell, what law of thermodynamics does space colonization or exploration violate?  Last I checked such things do not involve perpetual motion machines, reversing a normally irreversible process, or absolute zero temperatures.  Or perhaps you're referring to the inherent energy properties of various fuels making such things impossible?  But wait, we've already demonstrated several propellant/oxidizer combinations CAN send earthbound objects to distant orbital bodies, and in recent decades we've developed propulsion technologies that can do so with vastly greater efficiency.  Did your statement about thermodynamics have a point?  I hope you weren't just throwing around that word in an attempt to show off.

Furthermore, the article you reference was from a biologist, not an engineer.  What are the odds he even knows the simple rocket equation, or the typical delta-V requirements to reach and land on other orbital bodies?  About the same odds of an engineer like myself knowing the detailed internal anatomy of a South American tree lizard.  In other words, very slim.  And that's to be expected... the two fields are very different.  So it's non-expert opinion, nothing more.  And the blog that the biologist referred to?  That's from a sci-fi author (presumably more knowledgable but still without an engineering or physics background), and the article is actually similar to the Do the Math article in that it highlights the difficulties in reaching distant bodies and colonization, but does not dismiss the possibilities or state it can't happen.  And even then some of the statements or assumptions are questionable, such as the one you quoted saying "I'll believe in people settling Mars at about the same time I see people settling the Gobi Desert."  Well news flash, but people HAVE been settling the Gobi for a long time now.  It's a funny coincidence, but in fact my wife's relatives on her mom's side happen to be among them.  I've been there myself, and while it's far from my first choice of places to live (too hot in the summer) there is a kind of beauty to some of the region. 

For any partially or fully self-sustaining manned outpost or colony beyond Earth, you ultimately need 3 things: to be able to get there (already demonstrated in part by the Apollo program and numerous probes), available energy (solar and nuclear are available options in most cases), and water or water ice (already demonstrated to be present in several other planetary bodies).  You could probably include soil and mineral deposits for agriculture and materials for construction or industry to that list, but in all likelihood any hypothetical colony would be located on or near such things.  And to get objects out of the Earth's gravity well, as long as you have some small industrial base, a source of energy to create hydrogen (you could use solar), and the proper skillsets you can do it.  Cheap energy is helpful, but not a necessity.  We were sending things into space decades ago when the economy and per-capita energy consumption was a fraction of its current size, so economy and energy shrinkage alone is not a valid argument against a functioning space program.  To be perfectly clear.... I am not saying that further space exploration & colonization WILL happen, I am only saying it CAN happen.  As Aaron put it, it's really a matter of "won't do it" rather "can't do it".  At present the larger obstacles are politics and societal priorities (or lack thereof) & dysfunction, not the limits of engineering.  To be fair, the political, economic, and social dysfunction obstacles are very substantial, but none of us know how these will develop and to what degree they will be present in the future.  It's premature to call space exploration "dead" when we still don't know what the end state of society will be like.

So xraymike, why then should we take your statements of the absurdity of it all at face value?  Do you have any expertise or background in this topic to validate your claim?  Because so far all you've come up with is we can't do it "because it's hard".  Well, so was the development of powered flight, or the mapping of the human genome.  It looks to me like your opinion or belief here is based on either preconceived notions or a failure of imagination (or both), not on actual knowledge.

For anyone who wants to dig deeper, I recommend The Case for Mars (you can preview part of the book at that link).  It's written by an aerospace engineer but most parts are written for the educated layperson.

- Nickbert

Thanks Nickbert

What a great promo! I'm getting my ticket now.

Oh...I didn't care for that collision part but I guess you have to take the bad with the good.

Mike-

I'm not sure where you read that, but it doesn't appear to add up.

The shuttle's external tank contains about 534900 gallons (or roughly 2 million liters) of liquid hydrogen, with an energy density of 10.1 MJ/liter, for a total of 2,000,000*10.1=20,200,000 MJ.  The two solid rocket boosters contain about 1110000 lbs (about 500000 kg) of solid propellant with an energy density of roughly 31 MJ/kg, for a total of 500,000*31*2= 31,000,000 MJ.  Add that up and you have 51,200,000 MJ of energy.

The best link for California gas consumption I found was here, and they approximated 10 barrels (1590 liters) per year.  The energy density of gasoline is 34 MJ/liter, making a total per-person consumption of around 54,060 MJ.

Divide 51,200,000 MJ (for the shuttle) by 54,060 MJ (for yearly consumption of one driver), and you get 947 persons worth of consumption.  Last I checked there were a few more than 947 drivers in the LA area  .  

Don't get me wrong that is still a helluva lot of energy, but nowhere the total gas consumption of LA in a year.  These are just very rough approximations mind you (and done in a Thanksgiving dinner over-eating induced stupor ), but even if the source data is a little off it still shows the scale of energy use is much different from what you stated.

As to your question of what fuel, it is quite possible to use solar energy to create hydrogen for use as propellant (which actually happens to be one of the best performing propellants).  Right now we use fossil fuels to do so because it is currently easier/cheaper, but we can do the same with solar and an available water source.  It would take a little time to create 2 million liters worth of liquid hydrogen, but then again rocket launches are not an everyday occurence either.  Like I said before, cheap energy is really helpful, but not necessary.  If people want it badly enough, it's possible to do.  I'm not saying they WOULD make that decision, only that it remains an option should they so choose.

- Nickbert

Nickbert,

   I'm taking the position that Hawkings proposed. What on earth was he talking about when he said:

"Our only chance of long-term survival is not to remain lurking on planet Earth, but to spread out into space."

And what were you talking about when you said:

But your work is invaluable, despite what I have said.

Having answered your question in my last post, I also have to say that NASA and space exploration would be one of the last areas I would defund if I had any say in the matter. I was just answering the practicality of colonizing alien worlds with humans at the present time. Gotta eat turkey now. Happy Thanksgiving. 

The position he took was simply to have human settlements beyond the Earth, which can mean anywhere from Earth orbit on out.  The context of his statements in the article was that we're heading into a century of extreme uncertainty and volatility, and his mention of aggressive and selfish instincts implies potential for major conflict or strife of some kind.  Given our military and scientific capabilities, this could result in either our extinction or an indefinite disappearance of anything resembling an advanced civilization on the planet (though one might say at present we only "resemble" an advanced civilization given our poor decision-making and management of resources ).  So from that one would assume that the intent behind his proposal is not to fix said problems on Earth, but rather preserve something of advanced civilization if not our species itself in case the worst happens.  And though he does not mention this, I happen to think there is also potential to improve ourselves through these endeavors.  As I mentioned in my first post, the degree of cooperation, forethought, and resource management required to live off-world just might diminish some of our more aggressive and selfish instincts.  As you rightly point out it's an incredibly hard endeavor, one that wouldn't tolerate the degree of those aggressiveness and selfishness that we sometimes see down here.  We still wouldn't be perfect, but we may at least learn some self-control over our more self-destructive instincts.

By your subject title in your original post ("the hard realities of thermodynamics"), you imply that the principles of thermodynamics are a barrier to what Hawking proposed, i.e. expanding manned space exploration and colonization in space.  The only way that happens is if such things violate one of the four laws of thermodynamics, or that the application of thermodynamics can prove that the methods used to get there or live there produce insufficient useful work to get the job done.  I was saying that this cannot be true, since we have already demonstrated the ability to both get beyond Earth orbit and to survive, and it is actually application of thermodynamics that allows us to do these things.  This is why I'm saying your mention of thermodynamics didn't make sense.

I happen to agree that right now would probably not be a prudent time to embark on greatly expanding manned presence in space.  The US and the world is in such a precarious situation that efforts should be focused on damage control and triage, and regarding space it would be wiser to focus on preserving and building resiliency in the capabilities we already have.  Embarking on such a project that requires very long term commitment in the face of an imminent fiscal & debt crisis would be a little like deciding to build an extension to your house during a hurricane.  But eventually the debt/fiscal hurricane will run its course one way or another and society will adapt to the new economic situation.  THEN it would be a good time to propose such a project on both public and private levels, while we still have some of our dwindling fossil fuel energy bounty left and before the race for resources gets even uglier.

One thing that gives me hope for the world's space programs is the example of the collapse of the Soviet Union; despite horrendous political, economic, and budgetary chaos, they still managed to keep their space program alive.

- Nickbert