Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 



Forgot your password?
typodupeerror
Check out the new SourceForge HTML5 internet speed test! No Flash necessary and runs on all devices. ×

Comment Re:The Moon is first (Score 2) 259

Unfortunately, the problems are considerably more difficult, and the transportation costs almost as high. All the moon buys you is faster transit times, which is only relevant if your need for help can wait for several days.

The moon is interesting primarily as a fuel, and perhaps eventually construction base, conveniently near (energetically) Earth orbit. And perhaps as a location for major radio telescopes on the far side, nicely shielded from Earth's radio noise. Mars is practically Earthlike in comparison.

Comment Re:What kind of drugs (Score 1) 259

Well, first we'll have to calculate just how many cannabis brownies will be needed to last 100 people for 80 days...

And where are you getting "one way" or "survival of the fittest" from? The current plan is to re-use the transport ships many times, with free return passage to anyone who wants it on the returning ships. And colonizing a new world is likely to be a deeply cooperative endeavor - humanity hasn't been particularly "survival of the fittest" since we started pre-chewing food for our elders.

Comment Re:What's missing (Score 1) 259

A magnetosphere is rather premature, don't you think? We'd need to build an atmosphere first - and if we can accomplish that in less than several thousand years, then, maintaining it against the slow loss to the solar wind should be child's play.

Meanwhile, building and maintaining long-term artificial ecosystems should provide a great deal of knowledge that will be useful as we navigate the drastic climate changes Earth will likely be undergoing over the next few centuries. As yet, we've only seriously attempted the experiment twice, at small scale, in the form of the Biosphere 2 experiments.

Comment Re:H20 (Score 2) 259

Mars has icecaps estimated to contain about 3 million cubic km of water ice, roughly 1/3 as much water as exists as liquid fresh water on Earth. There may also be useful amounts of subsurface liquid water - that's one of those as yet unresolved features we've found tantalizing hints about.

It also has copious amounts of almost laboratory-pure CO2 freely delivered everywhere on the planet. Between the two, you've got most of the bulk ingredients necessary to build biomass.

Comment Re:terraforming (Score 1) 259

Unfortunately, to do that you'll probably need to either bombard the planet with asteroids rich in atmospheric components, or build massive soil-processing infrastructure to release them into the air - Earth's atmosphere masses about 5x10^18kg, and even with Mars's having 1/4 the surface area to cover, 10^18 kg still amounts to 2.5 million kg of air for every person currently on Earth. You're going to need some serious infrastructure to deliver that kind of tonnage, and Earth is a long way away.

Comment Re:Antarctica (Score 1) 259

Well, maybe. If you were living in an Antarctica whose most violent winds were barely as strong as a light breeze, and had the benefit of incorporating free vacuum-thermos grade insulation into all of your structures and garments.. That super-thin atmosphere has it's advantages after all - "air temperature" is more of a theoretical concept, and in practice you need only guard against radiant thermal losses and conduction into the ground.

Comment Re:Better to dream big than not at all (Score 2) 259

Except the Moon is only a bit closer in terms of energy, and still too far away to evacuate anything more than a modest outpost unless you have a nice, slow, orderly catastrophe that allows you months or years to evacuate. You also have to deal with razor-sharp moon dust that, without the benefit of weathering, will make short work of moving parts and formerly airtight seals.

Mars also has far more accessible and abundant resources - a massive ice cap, potentially useful amounts of subsurface water, and all the CO2 you could want delivered to your doorstep. That and greenhouses can give you most of the raw materials needed to build and grow a colony, both in terms of biomass, and carbon and cellulose-based building materials - nanocellulose for example is translucent and airtight, with a strength comparable to aluminum, and can be produced from woody biomass with purely mechanical processing.

As for solar, the insolation on the Moon is more intense, but you'd need pretty huge batteries to hold you through the nights - they are almost fifteen Earth-days long after all. While Mars days are only 40 minutes longer than Earth's, conveniently within the range that most people's circadian rhythms can adapt to.

Comment Re:Terraforming teaser at the end? (Score 2) 183

Sure. But it will do so over the course of many thousands to millions of years, allowing plenty of time for "booster shots" of atmosphere. If we can create it in the first place, maintenance is probably a much easier task.

Even among naturally preserved atmospheres, there are other techniques for generating a magnetosphere should we decide to create one. Venus for example has no magnetic core, and is subjected to a *much* stronger solar wind, yet manages to hold on to it's atmosphere thanks to an induced magnetosphere generated within its ionosphere. Whether a similar process could be induced on Mars, I don't know, but it's proof that there's more than one way to generate a magnetosphere.

Comment Re:You can buy it that way (T3), makes you unhappy (Score 1) 220

Indeed. An explanation I recently came up with for caps, is that they shouldn't actually be measured in "MB", but rather in "MB/s * s" = "bandwidth used * time it's used for". You're not buying bandwidth, you're renting it by the second*. That you just downloaded 1GB of data is irrelevant to your ISP, they'd charge you just as much for downloading a single byte one billion times. (ignoring overhead issues)

Yes, technically the units simplify to the same thing, but like torque and energy, just because the units are the same, doesn't mean the things being measured are actually conceptually the same.

* Well, except that with data caps, instead of paying for actual usage, you're paying for a giant block of far more usage than you're likely to need, so that you don't have to worry about exceeding that limit and being cut off or hit with ridiculous overage charges. Which is arguably a total racket, but for whatever reason there actually seem to be a lot of people who object to the idea of being charged for their actual usage.

Comment Re:Wot? (Score 1) 79

The *roofing* is indeed much cheaper, but don't forget the cost of labor. Even with solar the cost of installation often exceeds the cost of the panels themselves.

Besides, if you're looking at financing a new roof + solar installation, even if it ended up shaving off only 10% it would make things that much more attractive.

And I seem to recall that Solar City offers something like "pay nothing up front and less than your current electric bill" financing options for standard solar panels. If you could get a new roof out of the deal as well...

Comment Re:Wot? (Score 1) 79

True. However, solar panels are already sturdy and weather proof all on their own, and get used for leaky carport and pavilion roofs, they're simply not designed to interlock in a weathertight fashion. It certainly seems possible that you could add the ability to interlock the already-weatherproof solar panels more cheaply than you could put a weatherproof roof underneath them.

Basically you wouldn't be eliminating the cost of the panels, you'd be eliminating the cost of the roof underneath them. As for aesthetics, I imagine it would be relatively cheap to make a normal roof panel that *looked* enough like a solar panel for cosmetic purposes.

Comment Re:Using bandwidth (Score 1) 222

You are correct, the megabytes are not consumed. The bandwidth though (MB/s of possible transmission speed) certainly is - it's an instantaneous resource - in this second, there's only so many megabytes that can pass through a single network link (be it a cell tower, fiber a optic cable, or whatever). And used or not, that data-transmitting capacity will be forever gone after the second is over. You can't use yesterday's unused bandwidth to transfer data today.

Peer to peer file sharing is inapplicable - it's a wonderful technology to allow data transfer loads to be distributed across multiple network links instead of all being bottle-necked by the source's single uplink, but if all of your nodes (including the source) are connected to the same wi-fi access point, you won't see any benefit. (peer to peer *networking* is a completely different concept, and not related to the topic at hand)

I think the issue is being confused because we're dealing with coincidentally identical units. Consider the physics example of energy(Joules) and torque(Nm). Basically unrelated concepts, and yet both have the same fundamental units, 1 J = 1kg (m/s)^2 = 1 Nm, they're simply written differently to avoid accidental confusion.

Similarly, we have two different concepts:
Data quantity, measured in MB
bandwidth consumption, measured in (MB/s of transmission speed) * (number of seconds it's used). = (MB/s)*s = MB

When a network provider charges you for 1000MB/s*s they are NOT charging you for the data you download, they're renting you the bandwidth you're using: Use 10MB/s of bandwidth for 100 seconds, and you've consumed 1000MB/s*s of bandwidth. That you've downloaded 1000MB of data is irrelevant to them, they'd charge you the same amount if you had consumed the bandwidth just sending a single byte back and forth a billion times.

As an alternative, they could charge you by the minute, just as they do with voice calls. But that would mean that if the network was congested, so that you were only getting 1MB/s, then it would cost you 10x as much to download the same file, because it would take 10x as long. That would certainly discourage using the network when it's congested, but I really doubt many customers would be happy with that arrangement.

Comment Re:Makes more sense (Score 1) 222

Not really - because the reality is that demand *is* elastic, and if you build out the network to provide 10x the bandwidth, you're going to have to charge 10x as much for access to support it. If your demand truly is inelasitic - real-time control systems, high-speed stock-trading, etc, then those costs are worth it and you buy dedicated access, but for most people they'd much rather pay 1/10th the price and just avoid video-streaming and other bandwidth-intensive uses during peak hours.

You're free to do the same - guaranteed minimum bandwidths are generally listed in the fine print of your contract - if your demand is truly inelastic, then go find the package with the guaranteed minimum bandwidth you need, and pay the huge premium to get it. That's is *literally* what inelastic demand means - that no matter how much you charge, customers will buy roughly the same amount.

Beyond that, it's all about how exactly you sell and shape your bandwidth usage. I see three basic billing options:
1) Dedicated bandwidth - as I pointed out above, that can get *really* expensive, for something most people aren't using most of the time.
2) Usage billing - basically how other utilities operate: you pay a fixed connection fee plus a per-MB charge, possibly with a premium for on-peak usage and/or a discounted rate for the lowest demand periods
3) Access billing - you pay a fixed amount to be able to use a portion of whatever bandwidth happens to be available at the moment. Tiered pricing could come in the form of maximum bandwidth limits, and/or congestion priority (e.g. pay 3x as much, get 3x the bandwidth of normal customers during peak hours), but there isn't really any convenient way to discourage on-peak consumption with this model.

And then there's caps, which are sort of the bastard offspring of usage billing - you buy far more usage than you plan to ever actually use, or expect to occasionally be hit with throttling, overage fees, or cuttoffs. Traffic-shaping is still possible by over/under-counting data during on/off-peak hours, but the effects are likely to be muted since most people will have a substantial amount of "head room" in their plan.

Personally, I'd like to see caps die a fiery death, but assuming traffic shaping is a desirable thing, that basically means paying by the megabyte instead

Comment Re:Makes more sense (Score 1) 222

No, but you do *occupy* bandwidth.

Actually, it's rather akin to a small water company drawing from a large river - there's very little per-gallon cost to the water company, more total water delivery capacity available than there is demand, and the infrastructure requires constant maintenance regardless of usage level, and has to be built large enough to at least take a fair stab at satisfying peak demand. One option is certainly to simply charge a flat fee for water access, and that works fine if everyone is considerate, but if you have a few folks that want to water their rice fields 24/7 you have a problem - they're consuming most of your delivery capacity, and that's especially a problem during peak usage hours. One of the simplest methods to discourage such abuse is to charge by the gallon - it's not really reflective of actual cost breakdowns, but it's simple and does make the people getting the most use out of the infrastructure pay a proportional amount toward its maintenance and expansion, which is at least superficially fair (and we primates have a concept of fairness written into our genes)

If you want to get more sophisticated you can charge more per gallon during peak hours, encouraging your heavy users to temporarily reduce their consumption, but that tends to annoy the vast majority - peak hours are peak for a reason, those are the optimal hours for consumption. Alternately you could throttle everyone equally during peak demand, which seems reasonable on the face of it, but may engender resentment among customers, especially if charging a flat rate: "why am I paying as much for my low-pressure evening shower as that guy is to flood his fields with a firehose most of the day?", and perhaps more significantly among the shareholders: "why are we charging the guy using 1/10th of our total capacity the same amount as the guy using only 1/10,000th?"

Now, obviously the guy flooding his field is happy with the flat rate, but everyone else would probably be happier if he paid 10% of the maintenance costs, in line with his usage, and they all got a 10% discount on their bill. And that's a problem. Assuming you start with two companies with similar customer bases, overhead, and profit margins, FlatCo charging a flat rate, while UsageCo switches to this newfangled usage-based billing, how do you suppose the market is going to respond? The normal customers will all flock to UsageCo, and the unprofitable heavy users will flock to FlatCo, requiring them to increase their flat rate until it's basically the same as the heavy users would pay, on average, at UsageCo - after all they still have to pay the same maintenance costs. At which point all the below-average heavy users will be better off switching to UsageCo as well. And the cycle will continue until FlatCo is driven out of business.

Slashdot Top Deals

Nothing is impossible for the man who doesn't have to do it himself. -- A.H. Weiler

Working...