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Comment Re:Spam (Score 2) 211

It's surprising because the peak of the sun's spectrum is in the green. So the plants ignore the strongest part of the spectrum. That is surprising.

There's nothing surprising here anywhere for people who have actually thought aout this. Please refrain from confusing your ignorance with some kind of general human lack of expectation of this very result.

- Some photosynthetic processes benefit from being executed as often as possible. They thus benefit from chemical processes that absorb in the red, because there are many more photons per wavelength interval in the red than in the green (as a matter of fact, in terms of photons per second per area per solid angle, the sun doe NOT peak in greeen. It peaks in the near-IR). Thus evolution drove towards an optimum of absorption in the red.

Some other photosynthetic processes need as much energy as possible. They thus benefit from absorption in the blue, since the energy per photon is higher in the blue than anywhere else that the atmosphere transmits.

There is thus no reason to expect any biological system to optimize for absorption in the green (other than for non-photosynthetic reasons like attracting insects or such). If the number of photon counts, absorb red; if the energy per photon is more important absorb blue. It would be a rather odd coincidence ever to find something as complex as a biosphere that just so happens to develop a chemistry where the two just so happen to be perfectly balanced in the middle AND is unable to develop more than one chemical pathway to make use of sunlight (photosynthesis has been re-re-re- discovered during evolution many times).

Comment Re:data recorder (Score 1) 347

it's 128MB. The first 64MBchip is addressed correctly, the second one is mapped into the rest of the 500GB (I.e. responds to the low-significant bits no matter what happens on the high end of the address bus). The FAT and the root directory end up in the first 64MB. Large data files end up "up there somehwhere".

It ain't exactly rocket science.

Comment Re:Enough is enough (Score 2) 159

Is it easier to carry a fat tube than a thin rectangle? Possibly.

No. Definitely not.

Anybody who has ever flown with a laptop (which will fit into any backpack) knows the practicality of that situation - but anybody who has ever tried to fly with any kind of tube, knows how next-to-impossible that is. The overhead bins are made for rectangular items, so is the space underneath the seat in front of you. And where do you put it after you unroll it?

What possible advantage is there to something bulky that cannot be stacked; when we've already figured out how to make it razor-thin and infinitely packagable?

Comment Re:Good for US economy (Score 1) 617

If anyone doesn't, they are opening themselves up to risk of lawsuit.

I think this is an understatement. What I read this to mean is "If anyone doesn't, they are opening themselves and everybody downstream up to risk of lawsuit."

So Dow uses your pipe to make some plastic that gets whole-sold to some manufacturer that makes high-quality cutting boards that you can buy at Bed Bath And Beyond. Apparently they're now on the hook too. And if I buy that cutting board to make sandwiches that I sell from a cart by the street, then I'm on the hook as well. And if my cart is located on MS's campus in Redmont and I sell my sandwiches to their employees...

Hilarity ensues.

Comment Re:No (Score 1) 370

And then you google him. Or not. In fact, I throw the card away as soon as I discreetly can (no point pissing off someone needlessly, especially someone with whom I'm clearly never going to have any future contact with.)

No, you wouldn't.

Maybe it bears mentioning on /. that I am NOT some mindless IT drone who met with you to sell you something. If you have my card in the first place, it means that YOU came to ME because I can make you clever aerospace gadgets that nobody else on Earth can.

According to Google, there's ONE other person on this planet with my first and last name. He's one of those mindless IT drones. Somewhere in eastern Germany. I think you'd remember that you came to southern California to meet me, not to Europe.

Comment Re:No (Score 3, Interesting) 370

Actually, that exactly what I have on my business card: my name. That's it. Not even my company. Makes people do a double take - and guess who they remember from that meeting: All those forgettable task-managers and project-element-managers and systems engineers - or that guy who just put his name on the card?

Comment Re:No.. that would be silly. (Score 1) 397

Modification of your OWN property is not a crime.

That depends on the property and the type of modification. If the "property" consists of certain (perfectly legal) chemicals, for example, and the "modification" consists of letting them undergo certain reactions that result in the creation of, say, explosives, drugs, or fertilizers(!) then that modification may very well be a crime.

Comment Re:Riiight (Score 1) 815

Eh - I didn't "sort by" anything - I followed a link from google.

Meanwhile, the links you provided look credible at first look, until you try to follow the links to the sources. For the Gold one, one of the sources doesn't exist. Two are simple PSEs with atomic numbers but no obvious information on abundance in the crust. The last one ( has an entry for abundance in the crust. The value is "p.p.m.: 0.0011". This would appear to be 1.1e-3 mg/kg, but the link you gave cites it as 4e-3 mg/kg. (and just in case there's something going on with molar vs "by weight", the entry for Lead at states 14 ppm and is listed at eoearth as 1.4e-1 mg/kg). There's something fishy going on here somewhere .

So it's up to you to back that up [...]

Absolutely. Of course. If I had had the slightest idea that the abundance of lead and gold are apparently either under dispute or otherwise apparently not known better than to within about two orders of magnitude each, I would have done some kind of research job trying to find something I consider defensible (and then presented the defense). It didn't occur to me that such a simple set of numbers could be in any way disputed or otherwise unclear - I did the exact same thing you did: hit up google and go with the first result I find.

This has made me curious, however, whether there even actually is a central authority in geophysics that would collect factual information about the Earth's composition and would have the citations into the peer-reviewed literature how this kind of thing is actually measured and what the error bar on it really is.


Comment Re:Riiight (Score 1) 815

Oh, a pretty plot on wikipedia says something. It must be true.
Never mind that the link given as a source for the graph doesn't actually have any numbers at all. Odd. It does have a graph, which itself doesn't give any sources either.

Let me try something revolutionary and enter "abundance of elements in the earths crust" into google and see what happens. Just for the sake of the argument let's skip wikipedia and its copies and the first link that I get is
Which is the first link I looked at before submitting the previous post. Check it out: Gold more abundant than Lead. Odd, eh? No source given.

Second link is
which appears to agree with the picture in wikipedia. And it's the only one I can find that actually cites a source: Mathematica's "ElementData[]" function. Makes me wonder what program was used to make the plot in the USGS article that was then apparently copied (uh, "vectorized") for wikipedia...

The next link that I get is
which doesn't have crust abundances. The closest thing they have is abundance in the ocean with Pb:Au ~3.

I'm skipping links, as they are about as useful as asking some guy at the bus stop. gives me the wild run-around without ever presenting me with a table with actual numbers (or even sources). I'm guessing I need to pay for it to get that service.

Next I find
which merely copies the plot from Wikipedia. It does give a table with numbers (unsourced) which does not appear to contain Lead at all. Stranger and stranger.

My next link is
but not only do I not see a table or anything similarly useful, a quick glance down the side-bar at the left makes me doubt this as a reference.

I admit to being baffled - there's wildy varying numbers out there and the only references I find are to mathematica (which, in turn, doesn't give me a reference at all on their web-page). nndc, lbl, - none of my standard sources appears to have that data.

At this point I'm not willing to accept ANY of the above as valid numbers (including the one that I happened to see on my first quick check) until someone points me to a credible source: who determined which number how?

Comment Re:Riiight (Score 1) 815

"We've perfected the transmutation of the elements! Heavy, lustrous gold can now be alchemically tranformed into LEAD!"

Given that there's more gold than lead in the Earth's crust, that's actually not a bad thing.

The only reason gold costs more than lead is the crazed speculators.

Comment Re:Nickel and Hydrogen? (Score 1) 815

Your comment doesn't make sense. If hydrogen is the only fusion reaction that produces energy then stars would collapse after enough helium accumulates in the core. That they actually collapse when fusion of iron begins indicates that iron is the first element that requires more energy to fuse than it produces.

And Nickel is ... heavier than Iron.


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Whenever people agree with me, I always think I must be wrong. - Oscar Wilde