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SpaceX Launches Load to ISS, Successfully Tests Falcon 9 Over Water

Immerman Re:Not sure about the recovery test (100 comments)

Of course they still have to neutralize the horizontal momentum, otherwise they crash into the ground with only a high horizontal speed instead of having a high vertical speed as well. All a separate landing pad saves them is the fuel required to fly back to the launch pad - but they'd then need a ship to carry the rocket from the sea-based landing pad, and then transfer it to some sort of overland vehicle capable of carrying a 200 foot long rocket massing over 500 tons. Considering everything I've heard is that flying it all the way back to the launch pad only adds a tiny percentage to the needed fuel, which itself is a tiny percentage of the cost of a launch, it seems like that's adding a whole lot of complexity for very questionable benefit, in fact I wouldn't be surprised if flying it back was actually cheaper than the alternative.

3 hours ago
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Beer Price Crisis On the Horizon

Immerman Re:not bad news for the rest of us (204 comments)

How does recycling beer-brewing waste as a cheap, nutritious animal feed instead of burying it in a landfill contribute to ocean acidification?

4 hours ago
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SpaceX Launches Load to ISS, Successfully Tests Falcon 9 Over Water

Immerman Cost breakdown (100 comments)

So, is NASA currently paying a nearly 3x premium to SpaceX just to get their technology off the ground or what? Not that I object to such long-term thinking, quite the opposite in fact, but I could swear the SpaceX contract was marketed as a cost-saving maneuver.

It says here that it currently costs $10,000 to get a pound of payload into orbit, but from TFA SpaceX has a $1.6 billion contract for 12 launches, and if the current ~5000 pound payload is typical that works out to ~$27,000 per pound. Granted, assuming SpaceX perfects the reusable F9 that stands to potentially reduce launch costs 5 to 20-fold, easily making it one of the cheapest options available, even assuming that the current contract strictly covers launch costs and profit and without any R&D budget. But it's hardly a cost-saving maneuver in the short term.

Also, gotta love the phrasing in the summary "In another win for the company, as the L.A. Times reports, SpaceX also has launched a re-supply mission to the ISS." As though completing the mission that's actually paying the bills was just an added bonus.

4 hours ago
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Russia Writes Off 90 Percent of North Korea Debt

Immerman Re:THROUGH North Korea?! (122 comments)

To *be* bat-shit crazy, or to *appear* bat-shit crazy? Appearing insane can be an excellent military strategy, especially if you're in an extremely week tactical position such as North Korea is in. It makes your enemies extremely hesitant to provoke you because you may quite possibly engage in a completely disproportional and/or unexpected response. Of course keeping up the appearance requires that you do occasionally actually engage in insane behavior, but a sane commander using such tactics will be extremely canny in employing such behavior only when a studied analysis of the enemy suggests that he can get away with it with minimal real costs. The fact that North Korea is not only still standing, but has managed to repeatedly milk the western world for lucrative concessions despite the apparent insanity of its leaders, strongly suggests that that is the case.

Of course the beauty of such a strategy is that your enemy can never be completely sure exactly how much is an act, and must moderate their own behavior in the face of that uncertainty. Would North Korea launch an all-out attack on our regional allies in response to some moderate provocation, knowing full well that they would be completely obliterated in response? Certainly not. Probably. We hope.

4 hours ago
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For $20, Build a VR Headset For Your Smartphone

Immerman Re:uh uho. problems.. (38 comments)

No, we don't know all the unspoken rules that govern a patent examiner - but we *do* know the official, written rules which do so - and those rules require them to deny patents on non-novel technologies, mathematical algorithms, abstract ideas, and many other things which nevertheless routinely receive patents. Perhaps the examiners are only following orders when they grant such patents - but their actions are still illegal (well, extralegal at least) and carry a massive cost to the economy and the pace of US innovation. And I for one feel fully justified in condemning them for those costs. "I was just following orders" has never been an excuse for unethical behavior, though obviously the hammer should come down even harder on the ones who gave the orders.

5 hours ago
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SpaceX Launches Load to ISS, Successfully Tests Falcon 9 Over Water

Immerman Re:Not sure about the recovery test (100 comments)

Well, if they managed to bring the thing to a complete stop 8m above the water and then just drop it, that's still an incredibly soft landing compared to the traditional method of dropping it from a few dozen miles up at high speed.

I would assume the rocket was unrecoverable in a "reusable" sense - as you point out it wasn't designed for a water landing, and there is absolutely no point in doing so since this was only a full-scale proof-of-concept "landing" before attempting it on actual land. At most they would be looking to recover the rocket to analyze it for flight-related damage that could help to improve the next rocket - after all this is the very first rocket to manage anything remotely resembling a soft landing after a real-world orbital launch, there could be a great deal to be learned from it towards improving the reusability of the next rocket they build and launch. Ideally by the time they're confident enough in the safety of the landing procedure to attempt it over land, they will have worked out enough of the kinks that they can actually attempt to reuse it. Presumably in a situation where success is not assumed. A high-risk, cut-rate orbital launch perhaps? Or maybe just just a test firing.

5 hours ago
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The Design Flaw That Almost Wiped Out an NYC Skyscraper

Immerman A clear lack of taste (136 comments)

I particularly like the part where LeMessurier, the structural engineer given most of the credit for this giant ugly glass-and-steel rectangle on stilts (with a *gasp* slanted roof, how exciting!) calls the Old Saint Peters Church that it was built to accommodate “a crummy old building the lowest point in Victorian architecture."

If that's the sentiment of the people designing our buildings, then it's no wonder that US cities are such colossal eyesores.

5 hours ago
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The Design Flaw That Almost Wiped Out an NYC Skyscraper

Immerman Re:Math (136 comments)

Actually no, the odds of collapse would be much lower, unless you are assuming that any storm capable of knocking down the building would automatically also cause a blackout that disabled the tuned mass damper that would otherwise allow it to survive. Without knowing the conditional probability of a blackout occurring during such a storm it's impossible to calculate the chances of a collapse.

5 hours ago
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For $20, Build a VR Headset For Your Smartphone

Immerman Re:How much WiFi energy? (38 comments)

I suppose ass-cheek-cancer *is* probably less horrible. For what it's worth though I've still yet to see any study conclusively linking cell phones to cancer, suggesting that the link is tenuous at best. The strongest link I recall reading of was a link to benign cancers along the auditory nerve, and the correlation was insufficient to make a confident statement that a link existed.

5 hours ago
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SpaceX Launches Load to ISS, Successfully Tests Falcon 9 Over Water

Immerman Re:Not sure about the recovery test (100 comments)

Why would you land at sea at all though? After the testing phase at least. Once they're confident that they can land as intended, then they would presumably land someplace convenient for recovery and reuse, most likely at or near the launch site - a location already equipped to deal with all the horrible things that can go wrong during a launch.

5 hours ago
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For $20, Build a VR Headset For Your Smartphone

Immerman Re:How much WiFi energy? (38 comments)

Consider this - your phone doesn't stop connecting to cellular/wifi networks just because the screen is off. How many hours per day do you suppose you microwave your nuts by having your phone in your pants pocket?

6 hours ago
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For $20, Build a VR Headset For Your Smartphone

Immerman Re:Google Glass (38 comments)

Why would you wear such a thing in public? VR and AR(including the crappy Glass implementation) are *completely* different concepts. Good luck walking down the street wearing a headset which completely blinds you to the world around you.

Not to mention that virtually all the backlash against Glass isn't related to people having a screen strapped to their face, but to assholes walking around with a *camera* strapped to their face, often in situations where it's completely rude to be taking pictures. If I can't tell whether you're filming or not, then the presumption must be that you are. And frankly if you're walking around filming people without their permission then an occasional punch in the nose would seem to be a fairly justified response. Reporters and paparazzi are no strangers to physical confrontations over such things, why should Glass wearers be any different?

6 hours ago
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For $20, Build a VR Headset For Your Smartphone

Immerman Re:Instantly the most practical solution (38 comments)

Except for the fact that there is no reason for a phone to have a low enough "full-loop" latency (motion-tracking -> rendering -> screen refresh) to avoid rapidly inducing severe nausea in most users. And positional tracking, another essential component to limit nausea, would likely have to be done through live image analysis on a camera video feed, introducing even further lag, and likely saturating the limited CPU power of even a relatively powerful phone.

This could be great for novelty purposes, maybe quick games that only last for a few minutes, or a new generation of animated View-Masters, but unless the phone is specifically designed to address the nausea-related issues it will be completely unsuitable for extended VR. Basically to work properly you wouldn't need a mounting bracket for your phone, you'd need a VR helmet with a removable screen that just happens to have a smartphone built in. At which point you've got a hybrid device that probably costs about as much as getting two dedicated purpose-built devices - after all small screens and micro-gyros are only a small portion of the total cost of either device.

6 hours ago
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For $20, Build a VR Headset For Your Smartphone

Immerman Re:uh uho. problems.. (38 comments)

Hell, back in the VGA days, or maybe it was even CGA, I had a few games that recommended making a cardboard "view box" to strap over the double-screen displayed on your monitor for the full stereoscopic effect. Before that the View-Master had been around for almost a century, and before *that* there were prism-based toys that did much the same with pairs of stereoscopic photographs. Doing the same F'ing thing with a mobile screen with built-in motion sensors hardly seems innovative or patent-worthy. Except perhaps in terms of the specific fastening mechanisms.

7 hours ago
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Kepler-186f: Most 'Earth-Like' Alien World Discovered

Immerman Re:Better leave now (221 comments)

Quite so. "Flat space" has zero potential energy, and any gravity well lowers the potential energy from there. In fact IIRC someone recently published a paper claiming that the negative energy of a gravitational well exactly balances the positive mass-energy creating it, suggesting that under the right circumstances (such as the creation of the universe) matter can literally be created from nothing.

However, gravitational energy is special in current physics in that it's the only energy field which is assumed to not generate a gravitational field of it's own - Einstein felt that doing so would be "double-counting". And that means it can't be used for bending space. Even under alternate theories which presume that gravitational energy does in fact generate its own gravitational field the effect is primarily to limit the extremes to which space can be bent - for example black holes become impossible. The extreme negative gravitational energy creates a "secondary" positive gravitational field that partially neutralizes it, limiting the curvature to something light can still escape. Such energy though would presumably still be unsuitable for spatial engineering where you need to create a net positive gravitational field. And I don't know that anyone has done the math, but it would seem possible that such limits might render wormholes and warp drives impossible as well.

"Freestanding" negative energy would seem to require something more exotic.

7 hours ago
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Samsung's Position On Tizen May Hurt Developer Recruitment

Immerman Re:What's the problem here? (81 comments)

Nothing, so long as they don't care if developers ignore their schizophrenic platform.

yesterday
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Kepler-186f: Most 'Earth-Like' Alien World Discovered

Immerman Re:Better leave now (221 comments)

I believed that for a long time, but actually if you get into the mathematics of Relativity it turns out that with a little cleverness virtually *any* FTL mechanism will allow you to travel back into your own past. I don't really understand the mechanism well enough to explain it, and can't find the nice almost-comprehensible explanation that finally convinced me, but it's the reason that many scientists assume that FTL is inherently impossible. In current physics the adage is: Relativity. FTL. Linear causality. Pick any two. All three can't coexist.

yesterday
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Kepler-186f: Most 'Earth-Like' Alien World Discovered

Immerman Re:People getting wierd about liquid water (221 comments)

That does sound very weird, and way too full of plot holes for my tastes. I mean I could see dino-sapiens escaping to Mars if it was postulated that it had been life-supporting at the time, but tiny lifeless Phobos? As long as you're going someplace that will need a completely artificial environment why not just go underground on Earth? And the aliens sound downright sadistic, murdering entire planets to study the deep-frozen remains that survive an interstellar journey? Or did they include an artificial sun as well? Either way the tectonic stresses of Earth-based rockets would likely be devastating.

Yeah, what can I say? I like my SF to be at least plausible.

yesterday
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Kepler-186f: Most 'Earth-Like' Alien World Discovered

Immerman Re:interstellar surveilance (221 comments)

Hmm, hadn't thought of that, and Google isn't turning up anything useful on the equations governing the diffraction limits of a gravitational lens as wavelength, eyepiece, and target distance vary - if anyone could point me in the right direction for those it would be much appreciated. I did find the results of some other people's calculations though:

That an eyepiece at 550AU could theoretically resolve 4m details from a target 10 lightyears away
That a double-ended gravitational bridge radio-link to Alpha Centauri would need only ~100mW transmission power to virtually eliminate transmission errors.
And that a gravitational bridge to a sunlike star in the galactic bulge (~27,000ly away) would only need a transmission power of ~1kW

yesterday

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