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## Comment Re: Rockets are too expensive (Score 1)333

You are confusing two different coordinate systems. Both can be true at the same time -- corkscrews and figure 8 -- but not in the same coordinate system.

Looked at from the outside, in the so-called "Galilean frame", you would see the satellite making corkscrews. Another observer on the surface of the earth would see the satellite tracing a figure 8, in his coordinate system.

Since your two coordinate systems are rotating with respect to each other, the parametric equation of motion looks very different. A fixed point in one necessarily traces some kind of spiral in the other.

## Comment Re: Rockets are too expensive (Score 1)333

I think we were thrown off point by AC, who doesn't seem to grasp that physical systems can be described in alternative reference frames.

I think he is trying to say that there is no such thing as a geostationary orbit, because satellites in that orbit are actually tracing out a circular (or even more pedantically, spiral) path.

I believe the responder was trying to point out, using the example of a rocket ship travelling to geosynchronous orbit, that "stationary" is a kind trick of perspective when viewed from the frame of fixed stars.

Of course in the rotating frame of where we happen to be sitting on the Earth geostationary satellites are indeed actually stationary.

## Comment Re: Rockets are too expensive (Score 1)333

geosynchronous satellites: when the sun circulates over the north pole and it causes the satellite to exhibit the figure 8 orbit

geostationary : are fixed (fiction) stations , allegedly ground based

That is the most garbled explanation I've ever heard of geosynchronous orbits.

A geosynchronous orbit is one with a period that exactly matches the Earth's rate of rotation.

Geostationary orbits are a special case of geosynchronous orbits where the angle inclination of the orbit to the Earth's equator is zero.

So: a satellite in a geosynchronous orbit that is also geostationary appears to continually hover 22,236 miles above some point on the Earth's equator. If it is in a geosynchronous orbit that is not geostationary, it will appear from the earth to drift north and south of the celestial equator, tracing a figure 8 against the background stars over the course of one Earth rotation.

Of course in both cases the satellite would actually be following an elliptical (in fact almost perfectly circular) path around the Earth. The "stationary" or "figure 8" thing is simply a trick of perspective -- the way car in the next lane traveling at the same speed appears not to be moving.

Yeah, most of you knew all that. But insofar as there's an explanation here, it oughtn't be gibberish.

## Comment Re:Poor on \$100k? Sure (Score 1)739

People can adapt to just about anything. If you live in a ditch, then a shack feels like a mansion. If the people around you live in mansions, a perfectly serviceable house seems like a shack.

It's the Red Queen's race:

"Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!"

And once you've adapted to running twice as fast, you'll have to run twice as fast yet again to feel like you're progressing.

That's why I say the most important thing in your profession, once you have achieved enough income to live modestly and set a little aside for the future, is to find work that is in itself rewarding.

## Comment Re:Less than public transit? (Score 1)323

That's not the point. IT's not whether any particular fed action is advisable or inadvisable. It's that the printing money analogy is broken.

## Comment Re:Less than public transit? (Score 1)323

That way the founders and investors could get out with their cash and Wall St. (read - your 401(k)) would be left holding the bag.

Only if the managers of your 401(k) were idiots.

After all, the Fed is pumping so much printed money into the system something has to soak up all that extra cash.

The Fed doesn't just "print money", either figurative or literally (the Treasury does the literal printing). It has several methods for adding money to the economy, all of which are quite reversible.

## Comment Re:"Research Projects" (Score 1)74

The problem is that all these attempts to interest kids in STEM are so earnest and dull.

What we should be doing is tempting them with mad science. You see? It's not all death rays and monkey testicle implants.

It's important to hook them by middle school, when the all important sense of being misunderstood is its keenest.

## Comment Re:Call me crazy... (Score 1)89

Well, they're both solutions. But they run afoul of questions. Which users benefit most from each solution? And if someone benefits most from the massive battery with conservative display and processor specs, can you sell it to him?

I'll tell you right here that I'd much prefer LG's approach, but I'm an engineer. I think about my requirements differently than most people.

## Comment US Life Expectancy is 91.9 years (Score 3, Insightful)108

If you're a woman in the top 1% by income. If you're a man in the top 1% it's 88.8 years.

If you're middle class you live about 78.3 years if you're a man, which is big step up from 1980, probably because of smoking. If you're a woman you live 79.7 years, a decline of a few months since 1980.

Now if you're a poor your life expectancy has declined since 1980, to 76.1 for men and 78.3 for women.

So here's the picture: if you're rich, medical advances since 1980 have increased your expected lifespan by about seven years. But those advances haven't had any effect on middle class lifespans. If you're poor you apparently are having difficulty paying for medical care at all, which is not surprising because health care costs have consistently outpaced inflation since the mid-70s. If you're a working poor American health care inflation meant you basically screwed by the 2000s: you were too rich for Medicaid, to poor to avoid medical care.

One more thing: US has a GINI coefficient (measure of income disparity) of 45. That's the highest in the industrialized world, and much higher than it's low point of 34 in 1969. Basically all of the income growth sicne 1990 have gone to the top quintile, in fact the lion's share to the top 5%. People at the 80th percentile by income and below have seen basically zero income growth when adjusted for inflation. And since health care inflation rises faster than inflation, it means 80% of the the US has seen a cut in its disposable income.

## Comment Re:So, America might have a lower life expectancy. (Score 1)108

Why single out one cause, when there's obviously many.

Take food. I live near a supermarket that is probably three times the size of the one my parents went to, but the produce section is smaller, the meat and dairy sections about the same size. The surplus acreage is taken up with cheap, calorie dense, no-preparation convenience food.

Or the fact that Amercians spend more time in cars than they used to, on average over 290 hours a year.

Here's another interesting fact: research shows that the portion size you choose is positively correlated to the size of the package you serve yourself from; this doesn't happen consciously, it's just that a cup of cereal from a 9 ounce box appears like a lot more than a cup of cereal from a 21 oz box.

The huge sizes are driven in part by an attempt to cut down on trips to the grocery store. American home kitchens are the largest in the world, and most of that is needed for storage because we don't do very much food preparation.

So if there's a single root cause it's the pursuit (sometimes failed) of efficiency; we have the wealth to try to reduce labor and time spent doing things, but our bodies are designed to spend time doing things.

## Comment Re:The US ranks with Mexico? (Score 2)108

Actually the number of Mexicans in the US has been dropping for years. That's because for years US politicians have been intent on turning us into a low-wage, non-industrialized nation run by and for an economic elite.

What's there to choose? They might as well go home.

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