Well, the lead is 11.34 times as dense as the water. So, yes, if you need 18 times as much water, then you need 1.59x as much water than you would lead, so presumably in the end, only 11.3 Saturn Vs for your lead spaceship.

On the other hand, can get water from plenty of comets out there, or a moon or two. Lead could be tricky. Not sure if saving on fuel matters that much. Water seems prettier too, and has other uses for humans as well :)

Not to mention the mass of the propellant, much less the nuclear fuel. And then there'd be the need for another 18 Saturn Vs for braking.

Unless, there's some orbit that could be managed using minimal fuel that passes both Mars and Earth regularly? :)
Then it would be "All-aboard the water bubble Mars-Earth express!" You'd only need to accelerate it once, and reuse it an unlimited number of times.

Er. 17k tonnes of fuel (that's what I get for putting a k in there).
Thaaaat's not so good. That's almost 9 Saturn V rockets worth :-/

Also:
http://en.wikipedia.org/wiki/Radiation_shielding#Shielding_design

Seems to suggest an 18:1 ratio. So, 33 metres of water, 590k tonnes of water, and almost 37k tonnes of fuel.

So, 18 Saturn Vs...

Cool. So the spaceship would be more of a small planet?
I mean, if they feel it would require 6 feet of lead, that would be 72 feet of water by your ratio.

22 metres of water. Assuming a spherical spaceship, with a living space of, oh, 20 metres in diametre (yes, just a WAG, I looked around, I couldn't find any estimates for transit vehicle sizes in various proposals like Mars One), that would be:
4/3*pi*42^3 - 4/3*pi*20^3 or 277k cubic metres of water, therefore 277k tonnes of water.

So, Wikipedia helpfully offers this calculation:
https://en.wikipedia.org/wiki/Spacecraft_propulsion#Power_to_thrust_ratio

Of 620kg of fuel mass to push a 10 tonne spacecraft. That presumably means a 277k tonne spacecraft would require 17 tonnes of fuel, not including the mass of the living quarters, nuclear power plant, thrusters, whatever... Maybe 20 tonnes of fuel?

That doesn't sound that horrible actually.

And we get a pretty pool too! Maybe it'd even sparkle with the lights off from high energy particles crashing into it. Just don't dive too far down, or you'd get irradiated as well as run out of air? :)

When I first watched Space:1999 season 1 in the mid-70s, one of the things they did made a big impression on me: Some of the episodes would end with something like this:

John: What the hell was that and how did we survive?
Victor: I don't know. We don't know. There's a lot of stuff in the universe that we have no idea about, and it could just as easily have killed us all. We survived due to sheer luck and not because we're anything special.

That's paraphrased of course, but compared to the tone and formula/attitude of all the other action and sci-fi on TV in that era, and it was downright subversive.

I must be getting very old. Back in the 8-bit heyday (1979-1983), Softside Magazine (for TRS-80, Apple ][ and Atari 800 users) used to have 2 submission contests that they ran in almost every issue: One line programs ( "one-liners" I think they called them) and 1K programs (program size without running = 1023 bytes or less).

The TRS-80 was probably the best machine for one-liners as a single line could be 245 or so characters long (the Atari was limited to 120 characters, but you could abbreviate some keywords, I don't recall the Apple ][ Basic line limit).

The one-liner I remember the most was a graphical version of the old "Lunar Lander" game for the TRS-80. Yes, graphical. A loop (X =0 to X= 127) created the lunar landscape, followed by a loop which updated the state machine of your ship (a single "dot" drawn with the SET and RESET commands) that factored in which keys you were holding down (PEEK of the keyboard matrix I think), and tested to see if you hit the ground with your velocity under some threshold. *THAT* single-line effort was certainly more interesting that the one presented here.

Requiring even a 90% threshold to pass a law, a supermajority, is still democratic. Everyone gets a voice. It just requires more people to agree before imposing something on everyone.

IMO there should be a higher threshold to passing a law, than there is for dissolving one.

Heinlein suggests this (among many other ideas just tossed out there) when they are forming the lunar government in The Moon is a Harsh Mistress.

Neat story. Decided to DDG for a bit more detail.
http://www.npr.org/blogs/krulwich/2011/10/03/140815154/dissolve-my-nobel-prize-fast-a-true-story

That doesn't prevent the passage of laws, it just requires a supermajority of 60% to pass, which, if the legislation is heavily controversial, sounds like a good idea to me. Prevent the whole 51% dictating to 49% thing.

Not that different from needing a supermajority to override a presidential veto really, except it works even if the president is of the 51%
Just one more check.

I was listening to an old episode of 2000 Ans D'Histoire where he was discussing l'Affaire Farewell.

The researcher he was interviewing noted that the upshot for the Americans at the time was that apart from needing to engage on a campaign of disinformation and sabotage to mitigate the damage, the scope of the Russian theft of technology and science from government and private research in the West indicated how hopelessly behind the USSR was.

And that, the course of action at that point would be to push the USSR over the edge through expenditure of resources.

His argument was that Farewell's revelations triggered the Americans to come up with Star Wars as a ploy to force the Russians to pour scant resources of their already disfunctional system into space weapons technology and into producing enough missiles to overwhelm the theoretical American system. So, this being a French program, he was suggesting that Farewell in a sense led to the eventual victory of the West in the Cold War.

What I got from it was that Star Wars might have been provocative and probably not workable, but it may well have had a legitimate strategy behind it. Reagan could have been selling an idea proposed by those who had studied the fallout from Farewell.

There were no unencumbered jpeg formats w/ an alpha channel out at that time.
Certainly nothing available in a browser.
There's some hope now, but not a lot of progress.

MNG had feature creep, but that's why there was MNG-lc and MNG-vlc.
Which was successfully integrated into Firefox as a drop-in replacement for libpng.

APNG is fortunately slowly being picked up. Maybe it'll even someday get accepted despite the mistakes it made and the division caused.
https://en.wikipedia.org/wiki/APNG#History

It's sad we lost like 12+ years due to some egos back then tho.

Oh well. Whatever.

I think JNG would have been a bigger selling point.
APNG doesn't offer much on its own. Heck, I'm better off just using a javascript to animate a PNG sprite sheet in terms of browser support. Also, MNG was already out there with existing implementations. APNG had to start from scratch.

To summarise, I think APNG took some slow progress at replacing GIF w/ MNG and extending PNG to lossy images, completely squashed it, removed features, caused a bunch of division in the community, and then was all surprised at the loss of progress.

Well, MNG might have had more traction if Firefox had kept support. Even for the "light" version of MNG.
Initially the accusation was that MNG took up too much space in Firefox (entire kilobytes more!) amusing in this age of slapping in megabytes of libs for the latest camera/microphone HTML5 support.
Anyway, the MNG guys went and stripped down libmng (minimal support) so that there was no increase in resulting size.

At that point, the reason changed to concerns about security. Which, is reasonable I guess, although I'd again point to all the libs they are just slapping in.

MNG had a lot of potential. There was the JNG - can you believe that over a decade ago we had browsers with lossy images with alpha channel?

Personally I think it was the fact that the people who were most active in killing off https://bugzilla.mozilla.org/show_bug.cgi?id=18574 were those who had created APNG.
I'd be fine w/ APNG even with the less efficient animation frames if only they hadn't killed off JNG to get it :(

Amusingly, I've the opposite experience.
USPS carriers, ridiculously incompetent.
I'm routinely carrying letters over to neighbours, sometimes several streets over, despite clearly marked, usually typed, addresses.

Then there's stuff that just never arrives, like Netflix.

By contrast, if I want something absolutely positively to arrive, such as a document that needs a signature, I'm going to use UPS.

For a mortgage payment... that should all be done online nowdays. Providing remote communities with some public terminals should be way cheaper than maintaining USPS.

Just for the heck of it, although you'd hope actual costs of a full system could be lower...

Shipping a 10 pound package from Washington, DC to Aleknagik, Alaska using UPS which is presumably seeking to turn a profit on this, costs $90.45

10 pounds would be ~160 letters.

That's 56 cents a letter for a bulk delivery.
That's really not that bad.

Now I'm assuming costs might be lower if UPS and FedEx went into general mass delivery, although, who knows, maybe UPS piggybacks an a USPS plane or something to get to Aleknagik.

IMO though, it isn't the end of the world if USPS shuts down most of their operations, I think we have enough alternatives these days, which is the other reason they've been losing money.