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Comment: Re:Isowhat? (Score 1) 95

This concept is known as isostatic compensation, and was actually uncovered by the famed British astronomer George Airy.

The work dates from M. Bouguer (he of the eponymous Anomaly) and the geodetic expedition to the Andes in about 1730).

It's from ; not worth further consideration.

Comment: Re:A large load of sheets from BB&B (Score 1) 150

I'd anticipate significatnt sublimation and thawing on even the backside if the solar sail does not reflect _away_ from the object.

Since at least some comets that cross Earth orbit (and are therefore a threat) have had insignificantly altered orbits for several thousand years and dozens of perihelia, then the lower limit of sublimation you're going to need to consider is under 1% per apparition. Even with a solar sail blasting the backside with essentially another Sun, you're still down in the 2% per apparition or lower range. (I'd guess lower). Comets on a sun-diving orbit are approximately half the threat of ones that don't sun-dive. The sun-divers don't get a second chance to hit the Earth.

But the idea provides far more available thrust and control than draping coverings directly on a tumbling asteroid or comet.

I agree on this point. But since the proposal is for a generic design to deal with any incoming impactor, be it comet, asteroid, or even generation ship, then a design that can handle any impactor without modification is needed. There won't be time to design a modification if it is actually needed.

Comment: Re:North Pole (Score 1) 493

by RockDoctor (#49747853) Attached to: The Brainteaser Elon Musk Asks New SpaceX Engineers

that brain teaser has been around for what, eons now?

I literally (not figuratively) cannot remember when I first heard that one, but I was using it to get a friend's head around spherical geometry in the mid-1980s, so I knew it long before then.

I'd finger Eratosthenes as the guilty party. Or a close contemporary.

Comment: Re:It's about money. (Score 1) 289

by RockDoctor (#49747833) Attached to: North Carolina Still Wants To Block Municipal Broadband

He was lying. [aside]You can tell when politicians do that by checking to see if their lips are moving.[/aside].

What a refreshingly open and honest political culture you have. Here, we can tell when our politicians are lying by their not being decomposing into putrid puddles of greasy bones. The only honest politician is a dead one. Dead and clearly decomposing.

Comment: Re: Sudafed (Score 1) 333

by RockDoctor (#49747817) Attached to: Genetically Engineered Yeast Makes It Possible To Brew Morphine

tasteless hops to make their piss water.

"their diabetic horse's piss", please. Go the whole hog on the (entirely justified) insult.

(The version I'm thinking of is $BIG_MERKIN_BREWERY$ sends crate of it's best product to Czech brewery $BIG_CZ_BRAUERIE$. Some weeks later a reply is recieved at $BIG_MERKIN_BREWERY$, which is opened with excitement : "Dear Sirs. We regret to inform you that your horse has diabetes.")

Comment: Re:The song remains the same (Score 1) 201

by RockDoctor (#49747747) Attached to: Baton Bob Receives $20,000 Settlement For Coerced Facebook Post

The policeman camera is the best reign of all,

From a country (most likely, this being Slashdot) where the reign of monarchs was overthrown by terrorists over two centuries ago, and where the national self-image is as a cowboy clutching the reins of his horse and riding off into the sunset ... I find the inability to distinguish the two homophones particularly hilarious.

And it seems to rapidly be becoming a more common misspelling.

Comment: Re:Get a second ethernet adapter. (Score 1) 384

by RockDoctor (#49747677) Attached to: Ask Slashdot: Best Way To Solve a Unique Networking Issue?
To be honest, I was thinking of a second laptop on a cart, with a bunch of cables hanging out of the back end of it. Possibly four laptops (TFS mentions VMs running XP so any brain-dead 32nd-hand laptop should have the necessary grunt) on a cart so you can do an entire island at a time.

- set out the cones to stop new cars arriving at the target island then hook up the cables as existing drivers finish and leave.

- set upgrade running on first system to be ready. When you're blocking on that pump, swap to starting the process on the next available pump ; lather, rinse, repeat until all 4 are running away.

- meanwhile, start moving the cones so the first machine to be finished will be the first available to the next customer, and you're ready to start isolating the first pump of the next 'island'

If you can spread things out evenly, then your maximum hanging around time has dropped to 7 and a half minutes, and if there is any significant amount of user input, your idle times are going to be shorter than that.

Though it is a networking problem, it's really an optimisation issue.

Comment: Re:A large load of sheets from BB&B (Score 1) 150

by RockDoctor (#49747137) Attached to: Ask Slashdot: Best Payloads For Asteroid Diverter/Killer Mission?

You can get a much, much larger effect by attaching a much larger, more easily manufactured and testable actual solar sail.

How are you going to do that attachment again? The attachment mechanisms for Philae worked spectacularly well given the amount of information that was available about the comet's surface structure ten years before contact. So we can realistically anticipate a similarly accurate degree of knowledge about the surface properties of the asteroid we need to manage in two years time.

Next suggestion?

Comment: Re:The issue isn't worth fighting over (Score 1) 293

Further to Itzly's reply, nor are there any volcanoes anywhere near the Larson B ice shelf. There are probably sub-glacial volcanoes in the hinterland of some of the more southerly ice fields and sheets of West Antarctica, but from the absence of ash bands in the surrounding ice cores, they're pretty marginal on the activity front.

Oh, BTW, we know from studies of Icelandic volcanoes that even quite minor sub-glacial eruptions tend to produce substantial amounts of ash because of the violent emission of steam from interactions between lava and ice.

Your hypothesis is superficially reasonable but is destroyed utterly by the facts of the situation.

Comment: Why care (Score 1) 167

by RockDoctor (#49713727) Attached to: How Spotify Can Become Profitable

but it can become profitable with some specific changes according to one analyst.

So, another attempt to get rich on music falls flat on it's face, burning it;s investors arses in the process. And why should anyone care? If we believe the bullshitters, the entire music industry needs to die so that people can pay musicians directly, instead of letting the money be stolen by the music industry.

Well, that'll be great. And if the music industry goes down the shitter and takes the musicians with it, who's going to care?

Comment: Re:And what of false positives? (Score 1) 94

by RockDoctor (#49673089) Attached to: Can Earthquakes Be Predicted Algorithmically?

Any seasoned geologist can do that these days, we've known about earthquake predictors for quite some time and given the measurements,

Citation required.

If this is true (which I strongly doubt) then the geological press would be more full of it than if NASA launched a faster-then-light space ship and came back with a pointy-eared Buddha. Because there has already been a Buddha, but an effective earthquake prediction methodology would be something startlingly new.

Citation required. Journal name, volume and page number.

Practical people would be more practical if they would take a little more time for dreaming. -- J. P. McEvoy