It's interesting that ULA has such a different approach to reducing the cost of space exploration, by using fuel from the Moon. For them that makes a lot of sense. The upper stage of a rocket already get's pretty much into orbit but currently leaving the spent stage in orbit has no value. If you could cheaply refuel it from the moon though, suddenly it's a useful vehicle again.
That calculation doesn't apply for Spacex though because they're planning on making their main booster stages reusable. That would dramatically reduce the cost of putting fuel in orbit directly from earth. No detours to the Moon required. Space technology and the future of space exploration has never been more exciting.
Wish I could upvote more. This is why private companies need to be in the space industry. They do things more efficiently because it's going to cost them and their shareholders if they don't. I was thrilled to see the ULA slides about their cislunar roadmap. I was born 30 years too early I think...I likely won't ever get to space, but maybe my kids will.
It also costs governments to do things inefficiently. Money spent on something is not spent on something else regardless of what organization spends it.
Bush rode out the STS program way after any sensible retirement date. Then his team threw together the unfundable and questionable Constellation program. NASA was "asked" to do this and couldn't for a variety of completely predictable reasons.
Obama stepped and called Constellation "over budget, behind schedule, and lacking in innovation." And he was right. He tasked NASA to build out the Orion/SLS and continue to fund the Commercial Crew and Cargo program that funds companies like SpaceX. This was done in NASA Authorization Act of 2010, a measly 5 years ago, which is nothing in human spaceflight engineering timelines. Its kinda incredible the SLS and Orion are where they are at considering the very short timelines involved. The debut flight on the SLS is in 2018 and I believe Orion is either completed now or will long be completed by then.
On top of it, NASA keeps hemorrhaging money to the Russians for Soyuz lifts instead of funding these programs. Charles Bolden writes:
"Since 2010, the President has received approximately $1 billion less than he requested for NASA’s Commercial Crew initiative. During this time we’ve sent $1 billion to Russia."
Congress needs to fund these programs if you want them to happen. NASA can't work without a proper budget.
Nasa has been a political football for decades now. Only a unified national resolve to explore space will cure this problem, and we seem to be far from that unity. Half the country believes it's a waste of money (even though Nasa's whole budget was less than the one time bail-out of GM and Chrysler). Heck, 8% of the country believes the moon landings were faked.
Just why would you write it like that? Why not just use the standard km/h? There also should be a space between the number and the unit (narrow non-breaking is best for this)
Four [perhaps] plausible explanations in no particular order of importance.
1. Ars is written for general readers, i.e. it ain't a refereed technical journal.
2. Though there will be only one Will Shakespeare, the English language licenses authors to coin words [and quine quines].
3. Usage is hard, even when referencing the scientific "km/h".
4. Bespoke fact checking is expensive and the internet makes all grammar errors shallow.
My take is that while accurate attention to the specification of velocities is critical to space travel it is not nearly so to the thrust of the article. Boosting research there would little lift the major point. [caveat] I admit to the belief it's almost certainly a calculated mixture of time/money investment relative to the intellectual payload and the magazine's mission.
My pet theory is that some people hear words in their heads more than others while reading. I personally hate reading past stuff that I don't know how to pronounce. "regexp", "fn", and the like really bug me. ("regex", "fun", "func" would be my preferred alternatives.)
So when I read "kph" I read "kay pea aich" which is pleasing, while "km/h" is ambiguous. Rationally, I prefer "km/h", but I am irresistably drawn towards "kph". Seriously -- for me at least, the effect is very strong.
It's a bit off-topic, but kph is not common in my experience. I have a good explanation: this is metric, which is a very convenient system. If you want to express one measure against an other one, just use measure1/measure2. €10/meter, 25kg/liter etc. You can be more verbose and replace "/" with " per ".
Adding constructs like kph sounds like the reintroduction of foot and elbow sizes in the system. Please keep it consistent. /end of rant
It is consistent. It's consistent with mph, which is what people have been using for decades to measure speeds.
Using a / is technically correct, sure, but it's also technical language and where I'm from people are unlikely to use that. They simply wouldn't think to abbreviate the 'per' in 'kilometres per hour' to a slash, any more than they'd think to abbreviate 'miles per hour' to 'm/s'. So, kph.
That would be actually confusing as m/s usually refers to meters in second. I would intuitively assume that mps is miles per second, but it would feel strange.
I fantasise that in a parallel universe US, kilometer is considered a singular base unit whereas kilometre is thousand metres. This allows one to write "kph" instead of "kmph" when they want to be consistent with "mph", without getting odd looks from others.
When author can't even get units/symbols straight, it always makes me wonder of his credibility, especially if article aims for technical/scientific title. It's XXI century, there's no need for homebrew metrics anymore.
The actual title is perhaps more political than technical: Why we’re going back to the Moon—with or without NASA. Hacker News has committed a bit of editorial discretion, it appears.
That (with the exception that they're taking the water to water-impoverished Mars, rather than Earth orbit or California) is basically the plot of The Martian Way by Asimov.
Unfortunately, it doesn't work that way in real life, because Saturn's rings are more like diffuse snow flurries than mountain-sized ice chunks, as cool as that would be. And coupling your little interplanetary probe to an ice mountain really cuts into your delta-V numbers.
Hm, you're right, largest chunks are said to be several meters in diameter. They'd probably have to drag the rings with a ginormous net to achieve the same volumes.
For propulsion, I would go with a solar sail. Use it to get the craft to the rings, then it becomes a net to scoop up the water ice, and the craft could harvest the water for fuel to get home.
You could get a whole army of these things flying back and forth, and within a century or so, Mars could, as you suggest, become terraformed.
This opinion was born and raised in an environment of government funding for space. There is no fundamental reason why it should cost dozens of billions of dollars to get to space. If private industry brings it down to a cost more related to the true, fundamental price, it goes flying out the window. Merely millions to put people in space is of a kind with oil exploration, building transport networks, and all sorts of other situations where private industry under solid government routinely invest by the millions or even billions. At that point the argument actually completely flips around; anywhere we can afford to put a human, it is more cost-effective to do so than send a robot.
This is wrong. The fact is we take our humans back, but leave our robots in space. It's harder and more expensive to prepare a return voyage, and the robots can ultimately spend more time in space and for some applications that means it will be more effective at gathering data.
"Anywhere we can afford to put a human", and I'll remind you, that's under the new, wildly cheaper domain of space flight, not the current one. If only a robot is affordable at all, there's no debate about which is "better". Clearly that is not the argument being made, though, because then there's no point in even repeating the line about robots being more cost effective.
If space flight is cheap, you're better off sending a far more capable human than a robot, because if you're going to spend $3million for a robot or $5million for a human, the human is going to be more than 40% more effective than a robot. It's a totally different story than when the difference is $12billion or $500billion.
That depends on your value function. If you want to do science then yes, robots probably provide more bang for the buck. If you want to get at least some eggs out of the basket that is Earth, eventually you have to send up humans.
Physiologically, humans need shelter from the elements, a breathable atmosphere and nutrients. All of those are engineering problems.
What happens to a human body when it's spent long time in zero-g? I have no idea.
Can humans survive psychologically away from earth? Quite a many of us spend quite a lot of time just watching screens so the tiny boxes of first generation colonists might be livable.
If we belive physiological and psychological survival is feasible, then the only matter left considering I think is acquisition of raw materials and bootstrapping a colony-based industry.
I have no idea of the chemical composition of say, mars, and does is have all of the elements we need for our precious technology. But I would imagine earth is not the only place in the solar system with abundance of the all of the important ones.
This last one is a bit of an unknown to me but otherwise you would need to convince me pretty hard that colonization is not a feasible concept.
Every aspect of human physiology is highly dependent upon the very specific (and, as far as we currently know, unique) conditions found on Earth. Everything from the salinity of our bodily fluids to the atmospheric pressure and composition we need to breathe, the minerals we require in our diet, even exposure to sunlight and the diurnal day/night cycle.
At the risk of sounding metaphysical, we are as much a part of the Earth as your kidney is a part of your body. Yes, we probably can take your kidney out and keep it alive via artificial means for a certain period of time (it's just an engineering problem) but it is a rather large leap to do so permanently. It's worth asking whether the effort even makes sense.
Yeah, I see your angle. However, I'm writing this north of the 60 parallel and my country survives quite well in these conditions although they are quite different than the african savannahs native to our species. Although on a dark and wet december evening, I do wonder what my ancestors were thinking coming this much north.
For a human baby, the womb is the physiologically most natural growth environment. At birth we are separated from our mothers and the comforting heartbeat fades away to other noises. If I may respond to your methaphysical idea: perhaps earth is the womb of a space faring species, and our offspring will longingly observe it through telescopes like a person always misses her parents. But a longing does not incapacitate us, it merely tints the daily experience with a hint of bittersweet.
But in practice - human space flight at a large scale is a messy subject and like most topics of systemantics it will require endless amount of tinkering to even figure out if the idea is valid.
If we accept the premise that humans can't ever colonise off earth, then we should not fund robotic missions as well, since that assumption makes all space exploration and the science there pointless in the first place.
The point of organized missions to gather data from, say, Mars is that this data will help future human space travel efforts. If we accept that we're not going to do that ever then all the current activities are worthless and we can just stop them right now.
No. Understanding what's different about Martian geology and Earth geology, for example, can help us refine models of solar system construction, which in turn can refine how you model the Big Bang and the elapsed time of the universe.
And what's the point of doing anything if you're gonna die in 70 years anyways?
Just as most people can find value in doing things despite knowing that their ultimate life is rather short and finite, it's possible to extract value from doing research without trying to force it to be about a race surviving infinitely long.
Well, no, those beliefs are beliefs that things exist without any evidence. Beliving that humans can colonize another planet is a belief that something can be accomplished that we currently have no idea how to do.
200 years ago, there were no UFO beliefs and no "easter bunny" as we know it today, but there were sasquatch legends. The claims are as unsubstantiated today as they were then.
200 years ago some people believed the humanity could one day visit the moon. At the time they had no idea how, but 200 years later we have not only gone to the moon but become bored by it.
But I also don't see why you don't think we could establish a martian colony even with the technology we have today. I suppose I don't know what you mean by "sustainable," and if you mean truly terraforming the whole planet to make it a second earth, you're right that that is still the realm of science fiction.
But you don't need that. All you need is a large climate-controlled enclosure with hydroponic farming equipment. The martian atmosphere contains enough oxygen (0.14%) to keep this enclosure supplied, and water exists on mars, certainly in solid form. Such an enclosure would be sufficient for a person to live an entire lifetime without assistance from earth, which is a reasonable criteria for sustainability. The project would be economically possible, but probably politically impractical.
Radiation for one, but apart from that, in 2015 we don't even go beyond low earth orbit and we'll just have to wait and see but I'm guessing that no one will ever go to Mars.
No actual people have gone to Mars because its prohibitively expensive but also so incredibly unbelievably hard technically it will never happen.
Also undesirable. Why the heck would we want to colonise Mars? It's a desert where we can't live without life support. It's just sci fi to imagine we can or that it would be of value or sustainable. Earth is our home and will be forever.
As per the difficulty and cost of space travel - it took in the order of hundreds of years of development for several impactful technologies to be tinkered and optimized to a point where they started to make a difference. Steam engines, mechanical watches, etc.
I know historical arguments are usually kinda weak but objectively - space flight is still a young discipline.
I hope you respect that in historical perspective "we've never done it and so won't ever do it" is really weak. It will require empirical testing to figure out if spacefaring human civilization is a tenable concept. Large system cannot be reasoned with beforehand (well, if there are deep physical principles that are obvious then, yeah, sure, but at this point the problem space appears like more like a complex expensive mess of many uknowns rather than a physical impossibility).
This depends on your aim and what you consider value. There is also the point that robotic exploration is only politically supportable on the back of human exploration. Even the very rich and powerful have dreamt about being personally involved in human space exploration.
Andrew's point is taken. But human exploration requires so much technology just to make space survivable that there are huge ancillary payoffs.
At the end of the day, space is R&D. We can develop (and have developed) wonderful robotic missions and we should absolutely continue to do so. But we owe it to the world and ourselves to continue to research safer and cheaper ways to get humans to space. Eventually, there will be cities up there, and a trip to the moon or an orbital station will be just a bit more complex than a flight from London to Tokyo. But it's not going to happen without the necessary hard work and financial investment up front.
Also worth noting -- if we (U.S.) don't do it, China is still planning to put humans on the moon. We can watch and admire, or we can be in the race. Which would you rather?
I think this only holds true until the technology catches up. Twenty years ago the moon was probably best still observed and such with probes, but now as the number of options increase for how we can get there it might be viable to put people there permanently; provided private or government justification can be proven.
The moon problem I see is, what happens when a private company decides to make a profit off of the resources there? Pretty sure every government is going to scream bloody murder all the while trying to do the same but expecting their stance; as governments; to be more important. Should be an interesting time for rights when that occurs
This might be true, but you should also consider that sending humans up is more challenging. And if science rises to the challenge we will learn more from sending humans than from sending robots.
That calculation doesn't apply for Spacex though because they're planning on making their main booster stages reusable. That would dramatically reduce the cost of putting fuel in orbit directly from earth. No detours to the Moon required. Space technology and the future of space exploration has never been more exciting.