I flew in from New York last night and saw the Shuttle sitting on top of its 747 at the end of the taxiway. Awe inspiring and very sad for me to see. The entire plane literally jumped out of their seats to look out the windows on the side of the plane with the view (while the flight attendants hopelessly told us not to unbuckle).
But then I read about the pending Dragon missions to the ISS and I suddenly feel more hopeful than ever before and even the sniff of an asteroid mining company in the news today has me ecstatic. I feel like a boy again, watching shuttle launches on TV and excited about the future of space.
It's a great feeling to have after so many years of seeing it all get pissed away.
I think Tyson is wrong here in a way http://www.youtube.com/watch?v=3_F3pw5F_Pc, he needs to be spending his energies promoting commercial space development and just move on from the NASA model.
It'll be better, 30 or 40 years from now, to look back at NASA like we look back on ARPANet today -- as an interesting high risk R&D project that lead to transformative technologies that revolutionized humanity.
On the other hand, there are plenty of reasons that NASA could still be important moving forward. Commercial launch vehicles might be the way to go, but commercially funded space telescopes sound less likely. I don't see any organizations better suited to work on space research, and Tyson would be pretty disappointed if we stopped it.
Just so. NASA's truly great impact has been with the Hubble, Cassini, Voyager probes, Mars Exploration Rovers, etc. There's certainly no commercial interest in the foreseeable future for doing missions like that, and I certainly think its important that those kind of projects (and the primary R&D behind them) to continue (and proliferate!). That should be NASA's job.
Where NASA went wrong, however, was in trying to build its identity around the frankly rather prosaic business of trucking stuff to and around space. That's what the private sector really ought to be doing, with NASA as its most mind-blowing customer. I'm very excited to see things heading in that direction.
While NASA's greatest impact from a scientific standpoint has been through those programs, its greatest impact from a "get people excited about space so that they'll fund NASA" standpoint has come from the shuttle program, which is why NASA has spent so much money and resources on it over the years.
Edit: I referred to the shuttle program because it is the means through which we've gotten humans into space for awhile and I was contrasting it with the other list of programs.
Ah, that's the "no Buck Rogers, no bucks" school of thought -- which, actually, I agree with. There are several reasons why humans in space are a good and necessary thing, but as you say, people just need to relate back to the human experience in order to get excited enough to fund the thing.
The error you/NASA made is in believing that this excitement came from the shuttle program itself. No, it came from having humans in space, and the shuttle just happened to be the only way for Americans to do that. This doesn't mean that the excitement ever came from the shuttle.
Commercial vehicles such as the CST-100, Dragon, Dream Chaser, etc., will also all take people to space -- not only the same sort of astronauts who flew on the shuttle, but a far greater diversity of private astronauts as well. I'm certain that this will only get people more excited about space.
"Commercial vehicles such as the CST-100, Dragon, Dream Chaser, etc., will also all take people to space -- not only the same sort of astronauts who flew on the shuttle, but a far greater diversity of private astronauts as well. I'm certain that this will only get people more excited about space."
Yes exactly. Becoming an Astronaut has always been for a select, highly qualified few. And it comes with tremendous terrestrial sacrifices. Commercial travel suddenly makes is possible for anybody who can buy a ticket (and can sign the waiver forms) to go somewhere in space.
More importantly, the kinds of jobs that we've been putting our astronauts to work on seem mostly like their terrestrial equivalents of "truck driver", "construction worker", "janitor" and now with asteroid mining "miner". Some of those are high risk jobs here on Earth, but there's never been a shortage of people willing to do them in the commercial sector. There's no reason that those job categories require the creme-de-la-creme from humanity...with multiple Masters and Phds, decades in the military with multiple medals for bravery. That model came from the 50's.
Let's look for the guys that'll go to Afghanistan and drive a truck to deliver cigarettes to a remote Operating Base, or build whiskey bars in the Arctic. That's the new model for these kinds of space jobs. Hardy pioneer types with a healthy survival instinct and pants full of bravery.
Absolutely agree, but imagine if the total dollars going into space were a thousand times what they are today, because commercial activity could generate that with mining operations, space hotels, pharma work, whatever. Then a 1% share of that going back into high risk R&D and exploration (which is really what NASA's profile is) would be 10 times what it is today -- and it wouldn't be sliced up into non-high risk R&D that NASA spends too much time and money on today, like better space toilets.
And with a potentially large commercial infrastructure in place, assembling a NASA exploration gadget could be done at a fraction of the cost. NASA could in fact do many times the R&D in such an environment and make many Tysons very happy indeed.
You hear much less about it, but NASA is still funding space telescopes. Big projects like JWST, LISA, WFIRST, and Constellation-X have a hard time these days, but the Explorer-class programs are pretty active.
I don't really understand the Space Shuttle nostalgia. As a kid growing up it was such a disappointment. It looked bad ass. It looked like it could take off and land under it's own power. It looked independent and manoeuvrable. In short it looked like a spaceship. But in reality it needed giant external boosters to get anywhere. It had to have most of it's shielding replaced and be delicately positioned vertically before every launch. When it came into land it was an unimpressive glide.
The rockets and modules of past made so much more sense to me, they got people onto the moon. They got rovers onto mars and took photos of distant moons.
I'm kind of glad the shuttle is gone. It was an expensive and disappointing distraction.
I often wonder what NASA would look like today if it had gone in a different direction.
There's much debate about this issue, and it's hard to come down on one side or the other, but the Shuttle had unique capabilities that no other system has had.
Imagine building the ISS without the shuttle, for example. Imagine servicing Hubble. Imagine returning large objects from orbit safely.
The shuttle cost NASA a lot of money that's true, but it cost the US relatively little, and NASA did a bunch of truly amazing things with it. There's good reason to be nostalgic.
Don't forget the political context of the cold war space race. A good looking spaceship made for great propaganda. Even the soviets tried to copy it.[1]
Libertarian triumphalism always strikes me as so naive. Does anyone think SpaceX would be possible without decades of taxpayer funded research?
Or the freaking Web for that matter. Ground breaking research always seems to be funded by society at large and then spat upon as inefficient and stupid by the manly men who will now make a profit off of it.
Nobody is spitting on the ground-breaking research that NASA has done, and Elon Musk takes every opportunity he gets to thank NASA for doing that research and making their results available to him.
For the Shuttle, however, that research occurred in the early 1970s. The $200B that has since been spent flying the shuttle did not constitute ground-breaking research in any respect. It's simply operating a tragically expensive space truck. I'm thrilled to see the back of it, and hope that this will allow NASA to return to its primary mission of doing ground-breaking research, while buying its space truck services far more cheaply on the open market.
Consider that the same money could have paid several times over for a Mars Direct style program and permanent stay on Mars. The key to Mars (as opposed to the Moon) is being able to make your fuel from the Martian atmosphere, with an input of (solar?) power and some materials brought from Earth (5-25% of total mass). That means vastly cheaper upper stage, allowing for a for a continuous presence for a fraction of the Shuttle budget.
On the other hand, two orders of magnitude lower development costs for the dragon than for the space shuttle is phenomenal. Do you think NASA could do the same? I don't.
Libertarians certainly have something to crow about! It's amazing how much more can be accomplished by a private, selfish actor compared to a selfless government agency with the same resources.
> Libertarians certainly have something to crow about! It's amazing how much more can be accomplished by a private, selfish actor compared to a selfless government agency with the same resources.
Once the basic research and exploration has been done, certainly.
It's as if different kinds of organizations were both good at doing different kinds of things, and both worthy of a place in society...
> But the Dragon still cost less to develop than a single launch of the NASA space shuttle. That's remarkable.
It's called "standing on the shoulders of giants". I'm glad the industry is at a point where it can be run by companies instead of governments, as I'm sure it will be more efficient, and likely innovative as well.
But those of us without an ideological axe to grind are pointing out that it got to this point thanks in no small part to government involvement.
It's not just a rocket, it's a rocket capable of reaching orbit and returning [1]. But the things that NASA (along with russian space agency and others) did was things like figuring out, e.g., reliable ground-orbit radio communication, deployment and use of satellites, and a hell of procedures regarding pretty much everything from setting up a spacecraft, to lauching it, to orbiting, deorbiting and landing it, not to mention occasional orbital transfers to other planets. And let's not even get started about ground-side logistics.
There is LOT more to a space mission than just building a rocket. NASA and others did a fine job of doing that, and building neccessary experience in the process.
If the basic research was done by the Germans, what was all the research at NASA about?
Libertarians virtually never have valid points, private industry efficiency is one of the most common urban myths. The incentive for efficiency is valid, but the efficacy and safety issues almost always outweigh it.
I'm excited for the future of private spaceflight, but I am hoping that this allows NASA to contract for cheaper launches while maintaining their scientific research ability.
What private company could survive the Hubble debacle, for example?
I would hope that even the most ardent libertarian would concede there are some technical differences between lobbing explosives across the English Channel, and sending a man to the moon and bringing him home again.
It would happen if there was enough demand for it, just like the first power plant, the first radio, the first car, the first steam engine, etc.
None of these items were developed in a vacuum; it's almost impossible to separate private and public contributions once you start talking about education and the public safety/infrastructure that created the right environment, but I don't think it's fair to imply SpaceX would never have happened without NASA or other public research. History, at least, has presented some counterexamples.
Does anyone think SpaceX would be possible without decades of taxpayer funded research?
Yes.
Would SpaceX be happening now if there had never been a Space Shuttle? Quite simply we have no way of knowing and we never will, because we can't roll back history, change variables and make new experiments. But there's no particular reason whatsoever to think that the technology required by SpaceX would not (have been|be) developed just because it wasn't funded by taxpayers. If you're going to play with alternative scenarios, it's equally possible that privatizing space travel research decades ago would have led to more progress, not less.
But, for better or worse, we have what we have here today. I don't think any Libertarians are playing "triumphalism" here, so much as just pointing out that now is clearly a good time to start transitioning certain elements of space travel to the private sector. It's fun to argue about what might or might not have happened under other scenarios, but it's not a very productive discussion.
"Interstellar"?! Aren't we feeling overly optimistic today?
With current technology (and not inventing too much new physics) interstellar travel takes so long that, in order to be an effective investment, it would require an out of this world ROI.
Say you can launch an expedition to the closest solar system for a billion dollars (NASA certainly can't, but we are talking privatization) and have it return to Earth in four (I want to keep my numbers round) hundred years. In order to be preferable to US Treasure bonds (generally considered a lame option, but we are thinking very long-term), our expedition would have to bring back about about 3.7 billion dollars worth of stuff.
The billion dollar figure and the 400 years period are both ludicrously optimistic. In order to be back in 400 years, you'd have to fly at 0.02c meaning you'd have to spend 18,000,000,000 Joules per gram of spacecraft for each delta-v. That's 72 GJ, or 20 MWh per gram. And that's with a 100% energy efficient propulsion system (which would require some new - and very fancy - physics anyway).
"Interstellar" travel will likely never happen. The distances involved are so vast as to boggle the mind. Private ventures offer the promise of opening up space, but they won't break physics.
Like it or not, we as a species are stuck here, likely forever.
Such pessimism has nothing to do with fundamental limitations.
Once humanity has had perhaps centuries of experience with orbital habitats then the idea of a large "generational" starship won't seem so unlikely. With functional fusion power and highly efficient recycling systems the ability to have an interstellar city ship which spends hundreds or thousands of years isolated from the rest of civilization may not seem so unlikely.
Also consider that interstellar space holds far more destinations than we have currently cataloged. Begin with a colony near a comet out in the deepths of the Oort cloud. Then make a hop to another comet, free roaming planet, brown dwarf, or red dwarf that is very likely to be within a single light year distant. At each destination repair, refuel, resupply and move on.
In a time span of only a fraction of the age of human civilization significant populations of humans will spread out from our Solar System and diffuse through interstellar space.
Constant 1g acceleration makes nearby galaxies accessible, nevermind nearby solar systems.
"Break physics" is relative -- things which can be allowed by the laws of physics can be so humanly implausible as to be useless to discuss.
I mean, let me just be totally clear about this. In relativity, to get your time dilation factor γ up, you need a lot of kinetic energy K. How much? Well E = γ m c² = m c² + K, so K = (γ − 1) m c².
If you wanted to go to the nearest galaxy -- which is 25,000 light years away on the other side of the Milky Way -- and you wanted to do it with any sort of vehicle in 25 years -- you would have to take along about 1000 times the mass of your vehicle as fuel. More importantly, whatever fuel you're using to accelerate you're also using to decelerate, so you actually need 1,000,000x fuel to start with, to get your 1,000x fuel up to speed for most of the journey. So your 10^5 kg shuttle orbiter would need to come with 10^8 kg slowdown fuel. That's what we're sending around, you've got to build the Great Pyramid at Giza out of antimatter and find a way to carry it with you, just to get the shuttle to do this in a reasonable time.
Now c² is about 10^17 J/kg so we need about 10^25 J to slow down, and to send this would require 10^28 J. For perspective, our largest nuclear blasts (Tsar Bomba's 50 megaton yield) are 2 * 10^17 J, so you'd need fifty million of those to launch. Or you could just carry the US with you, that has an annual power consumption of 10^22 J -- wait, make that a million copies of the United States, before you could launch.
Of course, antimatter is unstable and you might want to carry the Tsar Bomba around as a massive fuel source instead, but the Tsar Bomba actually only carried an energy yield of around 10^-4 m c², so you would need to have 10,000 times more mass (10 million space shuttles to decelerate your one) if you wanted to do it with nuclear bombs.
I don't think rockets are feasible for interstellar travel for the reasons you state. Beamed propulsion is probably the way to accelerate. Magsails can be used for deceleration. This gets around the nastiness of the rocket equation.
Beamed propulsion gets around the rocket equation, but trying to beam energy to something receding at exponential speeds doesn't sound that much easier. It would pose an exponentially decreasing target, so to get around the diffraction limit you'd need an exponentially increasingly large collimation mechanism.
Beamed propulsion gets around the rocket equation, but trying to beam energy to something receding at exponential speeds doesn't sound that much easier.
If you're making a mathematical argument, be sure to do the math. Nothing's going to be receding at >exponential< speeds. (It would be nice if we could do that trick.)
to get around the diffraction limit you'd need an exponentially increasingly large collimation mechanism.
Change targets to Proxima Centauri, use magsails to decelerate instead of jettisoning the outer mirror, and the power and lens requirements go down by a lot. I suppose your point would be that they remain freakishly huge. True, but if humanity continues to progress into the solar system, it should be feasible for the much larger and more advanced economy.
be sure to do the math. Nothing's going to be receding at >exponential< speeds
Yeah, my bad. Momentary loss of order-of-magnitude sense. Speed will go as t, distance as t^2, so solid angle subtended as t^-4. That's still pretty rapidly shrinking, though nowhere near exponential of course.
Well that'd be a nice thing about relativity: from the point of view of the beamer, of course they're receding at a constant distance and their surface area decays like 1/t^2. ^_^
Yeah, sorry if that was misleading. I wrote something to this effect and then pulled it out:
"You're sort of right -- since rapidities are linear in relativity one also has v/c = tanh(a t / c), γ = cosh(a t / c), and that's in principle an exponential growth, so if you can keep up a constant acceleration at this rate for 8 years, you could get to γ ~= 2,000. But here's why maintaining a constant acceleration for 8 years is pretty much totally unfeasible: getting a γ around 2,000 requires carrying 2,000 times as much fuel as spaceship."
At some point I edited this out to focus on that main point without editing out the quote at the front. Sorry if that's confusing.
Well, I'm stating a basic constraint of physics: you have to carry around this much energy and it will require this much mass. You're making a certain assumption about the kind of engine and its exhaust velocity, and finding that there's a problem with low exhaust velocities. That's mostly correct, but in principle there are probably fuel sources which could achieve an exhaust velocity near c -- I'm thinking in particular if you were carrying matter and antimatter, and annihilated them in an ultrahigh-Q cavity with a small aperture to let the light out in only one direction -- or some really crazy futuristic application of lasing. You will still not get better than carrying thousands of times the mass of your spaceship for the deceleration phase, due to a basic constraint of physics.
It currently is, but there's no suggestion that it 'breaks physics'. Even resorting to generation ships, there's nothing in physical law that prevents colonization of the universe.
That's not really true. Even if you have infinite time, you can't sustain 1g indefinitely without infinite amounts of fuel. You're still subject to the rocket equation, so even without the problem of relativistic mass increase the amount of fuel you have to carry scales exponentially with your final velocity.
I would think HN readers would appreciate the futility of scaling up using algorithms that go as O(exp(N)) even if there's nothing in principle that says it won't work. Just saying "we'll wait until the computers are fast enough" is not going to work. Plus, when it comes to rockets, you're much more bound by practical constraints.
Just as an order of magnitude exercise: Suppose you want to accelerate with a super-efficient ion thruster with 16km/s exhaust velocity. To get 1km/s, you need 6% fuel. 10km/s: 87%. 100km/s: a fuel of 518times the payload. 1000km/s: 1e27 times the payload. For comparison, that means to accelerate a ton to that speed, you need a fuel amount equal to the mass of the Sun. (And at that speed, it would still take a millenium to go a parsec. Space is really effing big.)
All well and good...assuming that human life spans cannot be extended significantly. Fortunately, there are some very smart people who disagree with that assumption [1][2].
I think what it will take is mind uploading. Once a sentience can suspend until interesting circumstances are detected, I'm sure some wealthy people will go decide to go off explore the galaxy / take a punt on van neuman machine mining.
But then I read about the pending Dragon missions to the ISS and I suddenly feel more hopeful than ever before and even the sniff of an asteroid mining company in the news today has me ecstatic. I feel like a boy again, watching shuttle launches on TV and excited about the future of space.
It's a great feeling to have after so many years of seeing it all get pissed away.
I think Tyson is wrong here in a way http://www.youtube.com/watch?v=3_F3pw5F_Pc, he needs to be spending his energies promoting commercial space development and just move on from the NASA model.
It'll be better, 30 or 40 years from now, to look back at NASA like we look back on ARPANet today -- as an interesting high risk R&D project that lead to transformative technologies that revolutionized humanity.