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Comment: Re:No they don't (Score 1) 212

by CrimsonAvenger (#49373943) Attached to: Chinese Scientists Plan Solar Power Station In Space

Look at the image at the top of the page. Do you see it? That's Mir's solar panels after about *10 years*. Hubble replaced its panels twice over a period of 13 years. Space absolutely sucks for solar panels.

The Hubble panels were replaced to provide more power, not because the panels were broken.

Note that since the last Hubble solar panel upgrade, Hubble has operated for longer than 12 years (13 so far). Currently, they're expecting the Hubble to be operational for another three years. At least.

So, with Hubble as a data point, and 2002-era solar panels, we're seeing an expected lifetime of 16+ years (there's no particular reason to believe Hubble is going to fail due to solar panel problems as opposed to other issues).

Note that 16 year lifetime for the solar panels would increase the numbers for the space-based system by 1/3. Still behind the ground-based system, but not by very much (~89%, comparing 2002-era solar panels in space to 2015-era panels on the ground). And that's a MINIMUM for the space-based system....

Comment: Re:maybe because it's a quote (Score 1) 272

by CrimsonAvenger (#49373593) Attached to: Attempted Breach of NSA HQ Checkpoint; One Shot Dead

"To be or not to be", or, in it's C style syntax: "2b || !2b", is not a question at all. It is a tautology. It is true regardless of what semantic value you assign to 2b.

I gather you've never read the source material?
That particular soliloquy was Hamlet's musings on suicide as a solution to his problems....

Comment: Re:No they don't (Score 1) 212

by CrimsonAvenger (#49370089) Attached to: Chinese Scientists Plan Solar Power Station In Space

I just took a look at that site, and while in general I agree with his conclusions, I am perplexed by some of the math that he uses.

I don't necessarily agree with his conclusions, but agree that some of his math is...perplexing.

For instance, he gives a ground-bases system a lifetime of 40 years, but a space-based system a lifetime of only 12 years. Off the top of my head, I can't see any particularly good reason why a space-based system should be shorter-lived than a ground-based system.

If, instead, he'd assumed a similar lifetime for the space-based system, his conclusions would have been the opposite, since he'd have increased the lifetime output of the space-based system by a factor of 10/3, moving the 40K+ to 130K+ (nearly twice the output of the ground based system).

Arguably, a space-based system will last less time than a ground-based system. On the other hand, arguably, a ground-based system endures more weather events that can break solar panels, so the reverse may be true as well...

As to the Tg, it is possible that it will have a better value for the space-based system, since it can be beamed down to a location near where the power will be used (thus reducing line losses). This is not mandatory however, so it's possible space-based Tg will be the same as anywhere else (no reason it should be worse exists, but better is certainly possible). Even with Tg the same as ground-based, space-based solar would come out considerably better than ground-based so long as you assumed essentially identical lifetimes for the systems.

Comment: Re:And why not? (Score 4, Interesting) 187

Safe until it kills millions when a plant blows up.

Unlike, say, coal, which kills millions under normal operations, right?

Or didn't you know that routine coal-mining fatalities are a couple of orders of magnitude more numerous than all fatalities associated with nuclear power? Hell, coal mining fatalities in the 20th century in the USA ALONE were comparable to the death-toll from the Hiroshima and Nagasaki bombings.

And then there's the rest of the world's coal mining casualties, plus secondary effects from the pollution.

And never mind that nuclear plants don't "blow up". Unless you fill them up with TNT and set it off, of course.

Comment: Re:Tax (Score 1) 390

by CrimsonAvenger (#49366759) Attached to: Experts: Aim of 2 Degrees Climate Goal Insufficient

Nuclear is dead, I can't be bothered to argue about it. Ten years from now renewable energy will be a fraction of the cost of nuclear and will be the cheapest form of energy worldwide without any need for subsidy. 10 years from now if you suggest we use more nuclear energy, anybody who knows anything will frown at you like you're mad.

It's funny, but I remember hearing the same sort of comment back in the '70s during the energy crisis.

Oddly enough, it didn't seem to have worked out that way.

Comment: Re:Oh goody (Score 2) 343

by CrimsonAvenger (#49365903) Attached to: Former HP CEO Carly Fiorina Near Launching Presidential Bid

Wait until the SCOTUS tells states that immigration enforcement is a federal matter, and that states therefore cannot prevent illegal immigrants from voting or holding elected office.

While some elected office require citizenship, not all do, in case you are unaware.

However, voting requires citizenship at local, state, or federal level.

Which means that even if SCOTUS says that immigration enforcement is a Federal issue (it is, frankly), that won't result in any new voters until citizenship requirements are met. Though it might result in some new candidates for public office....

Comment: Re:Goddard and Von Braun (Score 1) 118

by CrimsonAvenger (#49365813) Attached to: SpaceX's New Combustion Technologies

As far as we know, there may be no way to produce or find and mine hydrocarbons such as methane. Mars's atmosphere lacks significant hydrogen content. If there's subsurface minable water, that could solve the problem, but only if there's plenty of it.

Hmm, methane is 1/4 H2 by mass, and 3/4 C...

Which means, absolute worst case, that we have to carry the H2 to Mars, thus giving us only a factor of four improvement over having to carry ALL the fuel to Mars.

If, as seems moderately probable, Mars has frozen water under its surface, you produce all the fuel there. Or, if our moon has H2O, as seems probable, then it's actually easier to ship fuel from Luna to Mars than to put the same fuel into Mars orbit FROM Mars.

Note that a mass-driver, a la "Moon is a Harsh Mistress" (which would also be workable on Mars, if you built one on steroids) would make the process even more efficient, in that all the H2O from Luna could be sent to Mars or LEO without having to burn any of it to get it off the moon.

Comment: Re:Bad name (Score 4, Informative) 178

by CrimsonAvenger (#49361877) Attached to: Commercial Flamethrower Successfully Crowdfunded

A flamethrower is primarily useful for clearing bunkers.
Squirt a jet of flame through the firing slit on a concrete bunker, and it quickly ceases to be a threat to the guys on the outside.

Like a demolition charge, it's utility is pretty limited, but when the right (or wrong, depending on perspective) situation comes up, there's no substitute....

Comment: Re:He's good. (Score 1) 198

by CrimsonAvenger (#49361653) Attached to: Prison Inmate Emails His Own Release Instructions To the Prison

Interesting that you'd pick those names. A quick google for wealth of US Presidents (adjusted for inflation), puts Bush at 15 (the elder) or 17 (the younger).

And this is as opposed to, say, John Kennedy (1), Lyndon Johnson (7), FDR (9), Clinton (10), who all have that peculiar D after their name.

And note that Obama is #21. Hardly poor by any definition of the term....

Note that I ignored the rest of the top 10 because they served far enough back that the Party they were part of had no real similarities to the current version of the Parties of the same name (once upon a time, the Republicans were the anti-slavery Party, not the Democrats, for instance).

Comment: Re:Stars collision rarity (Score 4, Informative) 233

by CrimsonAvenger (#49358611) Attached to: Dark Matter Is Even More of a Mystery Than Expected

What I find more interesting is why stars rarely collide?

Too much empty space.


Consider that for two stars to hit each other, they essentially have to pass within one stellar diameter of each other (absent gravity, but they're moving at over escape speed relative to each other, so gravity won't enlarge that distance a whole hell of a lot).

So, one stellar diameter is ~1.4 Gm for Sol. Nearest star is 40,000,000 Gm away. If that nearest star were headed toward us (it's not), it's course would have to be within 0.01 seconds of arc of our Sun in order to actually hit it.

And stars farther away have an even smaller course window to be in to smack us....

CCI Power 6/40: one board, a megabyte of cache, and an attitude...