When Snowden released documents that indicated that (amongst other things) Huawei had been compromised, I wondered if human intelligence or "social engineering" may have been used to obtain some passwords. If so, and if the Chinese govt. found out who (perhaps inadvertently) gave them away, that person would at the very least seen their employment terminated and perhaps even been terminated themselves!

Now with the frank admission that there are human spies at work in China for the NSA, I'm sure the Chinese govt. has redoubled their efforts to find (and kill) them. If so, then these leaks may be directly responsible for the deaths (probably after considerable torture) of individuals who, for whatever reason, were helping the U.S.

So, this is a very serious consequence of the leaks. Do you still agree that Snowden was justified in leaking all of this presumably without giving the U.S. advance warning of what he was going to release (so that they could get vulnerable individuals to safety?).

From the abstract: "life as it exists on Earth could not take place at z>0.5". I take this to mean (since I'm not a professional astronomer I am guessing that the variable "z" represents redshift) that life couldn't get started in the earl(ier) universe because the galaxies were closer together/with more gamma ray bursters etc.

So a partial answer to Fermi's paradox (where are they?) is that we are one of the "first" to evolve into sentient beings because for "most" of the period before life evolved on the earth the whole universe was mostly uninhabitable. Of course I put "first" and "most" in quotation marks because we're talking about billions of years here; maybe the universe became reasonably habitable "only" a billion years before life arose on planet earth; that's still a lot of time! That's why I say this might be a "Partial" answer to Fermi's paradox, there would still be time for some civilizations to arise way before us. Just not as many and perhaps no really ancient multi-billion year old civilizations.

I know that this is a hard choice (especially since I heard Alibaba has soared by 38% in its first day) but please consider the following:

About 5 years ago I stopped investing in Chinese companies. Why? Because I didn't want to support even indirectly a regime that, without apology, oppressed Tibet and supported the despotic regime of North Korea. I hold them largely responsible for sacrificing millions of my long-separated brothers (yes, I'm ethnic Korean) through starvation and torture simply to keep a "buffer state" in between them and the "capitalist" (ha ha, what irony) South Korea and U.S.

My stance was only hardened by their support, for purely geopolitical/economic considerations (OIL), of Syria and Iran (and, I think Libya). They and Russia have kept those regimes propped up and have made the tragedies in the Middle East even worse (of course America started it but at least we know now that most of us were idiots to be led by one). That's not to mention the authoritarian and despotic regimes that the Chinese GOVERNMENT is supporting in Africa purely for their resources.

Look, I know the West (and especially the U.S.) have done a LOT of bad things but the Chinese government doesn't even make a pretense of things like human rights, even in their own country. As I've said, they've been willing to sacrifice millions for a modicum of security (they could've asked the U.S. and S. Korea if, in return for not letting the Kims return to North Korea from one of their trips to China, we would promise not to put American troops north of the 38th parallel. As if S. Korea would even want American troops on the peninsula once the threat was gone). Now, living in S.E. Asia, I see firsthand how the Chinese government with its growing power is throwing away treaties and agreements it has signed in order to bully the Vietnamese and Philippines with their ridiculous "cow tongue" shaped demarcation of the seas. They are returning to 19th century "gunboat" diplomacy in the 21 century world.

I fear that as China grows ever stronger, they will continue to discard previous commitments to peace and will literally force their will upon the world. Is that what you want to support? I'm a realist, and I love my gadgets and my improved standard of living brought on by the flood of low-cost Chinese products (often produced with stolen patents and technologies but that's another story) and I'm not quite ready to live without. However, when there's a choice, when you can purchase something that is identical (hopefully) in every way including price to another but one is made in China and one was made in Sweden(?), I hope you'll make the same choice I do.

If the Chinese government, not the U.S. government had the power the NSA has; would any of us have any protection at all? Think of what kind of world that would be to live in. (That's what 1.2 billion people ARE living in).

(If you're wondering why I'm advocating not buying/investing in China and hurting Chinese citizens as opposed to just their government, remember that the world boycotted South Africa during their Apartheid regime even though it undoubtedly hurt many whites and blacks who were good people. And it worked.)

I would think that on such a wildly irregular body (the topology has been likened to a rubber duck), not only does the strength of the comet's gravity vary from place to place but the DIRECTION does as well. Something that appears to be "flat" or horizontal may, in fact, be a steeply sloping surface because the gravity vector is not perpendicular to the surface. Of course if it the surface were a liquid or very fluid particles then the surface would always be perpendicular to the local gravity vector but it appears as if it is made of a very heterogenous bunch of materials some of which are rigid (like rocks).

Then again, the surface gravity is likely to be so small (1/100th of a gee? 1/1000th of a gee?) that maybe it doesn't matter. From what I understand the probe has to harpoon itself to the surface; though I don't know whether that is because the gravity is so low that it might just bounce back off into space or because of the outgassing from the comet as it approaches the sun will threaten to "blow it away".

Too bad the comet's orbit doesn't have its closest point closer to the sun, I'd expect some real "fireworks". As it is, I'm not sure how much outgassing they expect.

Hmm... It's only ahead of the comet Siding Spring by about a month. Will it have time/fuel to "duck and cover" by getting to the far side of the planet before the close approach of the comet and the potential of a cometary dust storm that could wreck it? (Contrary to what some people think, it doesn't take much energy to change your orbital position IF you've got time. A simple change of 1 meter/sec from the thrusters will, after one year mean a distance of over 30,000 km. That simplification ignores some orbital dynamics but you get the picture.) Of course Mangalyaan doesn't have a year but it has much greater delta-vee capability, its orbital insertion burn is (I think) 1.6 KM/sec. And maybe it would've been on the far side of the planet anyway.

On the other hand, maybe it's near the comet NOW, or nearer to the comet than any other spacecraft. Perhaps it can take some good close-ups of the comet or at least see it from a different angle. (If it can see a full or partial eclipse of the sun by the comet, scientists may be able to determine the comet's composition or the composition of the comet's coma. It might be able to do it using radio wave occultation from earth.). In any case, it's good that there will be another spacecraft near the comet when it arrives at mars! Too bad the U.S. isn't willing to risk sacrificing one of its older orbiters (I think one has been around mars for about a decade) for a close flyby. (Again, given enough advance planning, a surprisingly small amount of delta-vee would be required to put one of the orbiters on a collision course, especially if gravitational chaotic resonances AKA "the interplanetary highway" were harnessed.)

Too bad we didn't know about this close encounter say a decade ago. We might have been able to send a probe that could've used mars' gravity to slingshot a probe into a matching trajectory with it so that, like the ESA Rosetta probe, we could rendezvous, orbit and land on it!

No, the Chinese government would probably WELCOME piracy of their O.S. because it would mean that their backdoored (it that a word?) O.S. was spreading even beyond what they hoped for.

The problem is that very few software companies like Microsoft would write applications for it knowing that the number of actual PAYING customers in China will be few. I think I read somewhere that a Microsoft exec. said they made more money in the Netherlands than in all of China because of piracy. The simple business analysis would be that they wouldn't be able to recoup their development costs for another platform, especially if it was pirated even more. Maybe if China told every software company that wanted to sell its products in China that they HAD to develop for their O.S. then they would actually get some native applications; I think it would be equally likely that since these software companies weren't getting a lot of revenues anyway (because of piracy), they might pack up and leave. That's not to mention what using the Chinese O.S. would leak (more like gush like a firehose!) to the Chinese industrial complex about their products.

I'm assuming that if the O.S. was "compatible" in the sense that it could run Windows programs using some sort of similar API or emulation that people wouldn't tolerate the poor performance/bugginess. I figure they'd just buy a computer with the Chinese O.S., wipe the drive and install their (pirated) copy of Windows for the best computing experience (if you can call Windows "best"!). Also, as bad as the NSA is, perhaps the average Chinese citizen would prefer some faraway American govt. agency snooping on their computer than the jack-booted thugs who would kick down your door in a moments notice which is basically the Chinese State Security apparatus.

This is a step along the road towards the Morlocks and Eloi of H. G. Wells "The Time Machine".

While this isn't as bad as "Gattaca" or "Brave New World" with their emphasis on eugenics; it's definitely not good for the concentration of wealth, power and yes, intelligence. When people can be ACCURATELY rated in terms of all their various intellectual abilities (as they already are in Chess ability) it will mean a further stratification of society and concentration of advantages.

While this has always being going on throughout history (and pre-history) if they really apply scientific techniques it could dramatically enhance its predictive power.

Maybe, eventually, humanity will start to diverge into multiple species. :(

While the solar wind will blow away the atmosphere in a (perhaps) short time geologically speaking, in a human timescale it would likely take thousands of years. By then, the humans could have implemented a giant electromagnetic shield (powered by sharks with frickin lasers) or have developed wormholes to directly transfer water from the water from Jupiter's moons or have migrated to the far reaches of the galaxy. Or have gone extinct.

Mars didn't become the dry desert it is today in an instant, I believe for the first half billion years or so it was a warm wet place (because of the cometary impacts during the chaotic early solar system. Hence all the evidence of flowing water). Plenty of time.

By the way, responding to other posts, it is very easy to move satellites great distances in orbit GIVEN TIME. A simple 1m/sec change in velocity would, after a month, result in change in distance of several thousand kilometers. Remember that these spacecraft are capable of quite substantial delta-vee changes (in the KILOmeters/sec). And that isn't even taking into account any kind of sophisticated planning by the mission controllers (like using gravity assists or chaotic gravitational effects "the interplanetary highway").

If this happened (optimistically) 50 years from now, we'd be able to deflect the comet to HIT mars, thus delivering a lot of water and warming things up a bit. (Only, I'm afraid, a little bit of terraforming, it would probably take thousands of such comet strikes to make the planet "habitable"). Or we could make it hit one of the moons and, if done very carefully, could deliver said water to possible Mars Moon colonists (but they'd have to find a way to keep the resulting fragments from ruining near-Mars space for space travels).

More realistically, I wonder if NASA (and the ESA) have plans to move their spacecraft for best viewing. If they're worried about damage, they could have them be on the other side of the planet when it makes its closest approach. If there are any spacecraft that are on their "last legs" (low propellent, malfunctioning equipment, no more spare reaction wheels), perhaps they could even make a very risky close approach!

I expect there will be some great images! (If the HiRes camera on the Mars Reconnaissance Orbiter can take 1m resolutions of Mars from orbit, it surely will be able to take great pictures of a comet only a few tens of thousands of kilometers away).

Before I read the article, I'd have been predisposed to agree with the poster who called this "The crackpot cosmology theory Du Jour". However the article does note that not only does negative matter possibly explain the current lack of detection of gravitation waves but (presumably unlike many other phenomena) predicts that if there is negative matter, we WOULD be able to detect gravitational waves but only above a certain frequency:

"the evidence that could back it up would be the discovery of the threshold frequency above which the waves do propagate"

If anyone who can read and understand the actual paper could tell us non-cosmologists when our improving technology might be able to detect gravitational waves above the cut-off frequency I would appreciate it. I mean is it technology that is (very roughly) 10 years away, 25 years, a century or basically only when we have god-like powers. I seem to remember that NASA was going to launch a space based interferometer with "arms" (free floating platforms) in a triangle 5 million km on a side. Would that be able to detect them? The whole point now isn't just to prove the existence of gravity waves but also negative matter (and the possibility of warp drives, yay!).

Actually, since (if I am reading the article correctly) they are looking for "higher frequencies", doesn't that mean the detectors should be smaller? ("arm" length shorter?) Shouldn't they be increasing the sensitivity instead? Or is the sensitivity increased by making the detector larger? I'm so confused!

So while I'm not ready to completely discount the stories of some Swedish "focus groups" (from the article), that anecdotal evidence would be balanced (overwhelmed? flooded? washed away? submerged?) by the experiences of tens of millions of rice farmers here in S.E. Asia (Mekong delta) who are literally seeing their future disappear before their eyes.

I think the rate of inundation by the ocean here (I live in Vietnam) is getting ridiculous, I frequently read in the local papers about KILOMETERS per year of rice paddies being lost to the sea; if not by direct submergence then by saltwater infiltration. I don't think there's a shadow of a doubt to these farmers that SOMETHING very bad is happening, though honestly I'm not sure if many of them have even heard of climate change.

Now of course there are a lot of other things going on that could be contributing to this. Overuse of groundwater, damming of the Mekong, improper irrigation; I'm not a climate scientist and I haven't screened out those effects (of course climate scientists who've looked at this closely have and they say the effect is real). But neither are those Swedes climate scientists so if their unprofessional opinion is that nothing out of the ordinary is going on, well I've got ten times (a hundred times? a thousand times?) more opinions here to counter that. Then again, there just might be some biases in listening more to white europeans as opposed to brown asians so maybe their opinions don't count. (I rarely if ever see any articles in Western media about the tremendous loss to agriculture that these farmers in the Mekong are facing; the rice basket to HUNDREDS of millions of people; nor do I see articles about the gloomy forecasts made by the governments here that in 20 years or so millions of people in cities like mine, saigon, will be flooded out).

I thought they meant WIRELESS automated remote charging. Like as in a laser or microwave beam transmitting power to a drone to keep it flying indefinitely.

I was wondering how much power it would require to keep a relatively small drone (but still capable of carrying a decent camera and transmitter) aloft. Of course the drone would have to be equipped with some sort of receiver capable of converting the beamed energy (visible light? IR? microwave?) into electricity. By "power" I'm referring to the power of the beam as well as the power fed into the transmitter (more because of losses).

Would there be a 10:1 ratio of power fed into the transmitter: power converted into electricity? 2:1? 100:1? I assume the beamed power would be way beyond what is regarded as "safe", certainly for a visible light laser maybe not for microwave. (That's why I assume it would be illegal). On the other hand, I assume a reasonably simple pointing system on the ground station could illuminate the (not too big) receiving antennae on the drone and would be able to compensate for sudden gusts of wind, etc. Of course the drone would have a small reserve battery.

What would be the effective range for a (practical) system? 100m? 1km? 10km? Anyway, it could be an excellent observation/surveillance platform. Imagine having a permanent camera flying (lazy circles?) above your house. Maybe if it was robust (and safe!) enough, power could be beamed BETWEEN drones (or even from orbit) thus getting rid of any range restrictions. On the other hand, if the tracking was really good, perhaps the "ground" station could be mounted on a moving vehicle; that might make the kind of flying companion drone, as seen on the cartoon "Speed Racer" where we have a robotic bird following the car, practical.

A really sophisticated long range drone might even have power AND communications beamed on a tight microwave beam from a (BIG) antennae in geo-sync orbit. Being able to loiter at almost any altitude over any area for any length of time might make this very valuable to the military (And a big drone could, of course, carry weapons). On the other hand, if the transmitter/receiver/converter overhead wasn't too large, it could be used in the exploration of other worlds. NASA was recently talking about having a quadcopter drone combined with a balloon in Titan's atmosphere; the drone would have to periodically dock to recharge its battery from the nuclear generator on board the drone. Well, this would allow the drone to keep flying without docking.

Since we don't know what the long term effects of low-gee gravity (Mars is 1/3 that of Earth) as well as the higher level of background radiation (Mars' atmosphere is too thin to screen out a lot it), we're going to be evolving a new race of Humans! (I guess we'll call them Martians).

This is the way Nature has done it for billions of years and it's worked. It's called Evolution. Sounds fine except Evolution works through DEATH, DEATH killing off those who can't survive long enough to pass along their genes to the next generation. So we may find that the first generation of colonists on Mars are going to have an absolutely horrific death rate (in addition to all the problems they'll run into with accidents, running out of supplies, breakdowns, etc.) but the next generation will be less so and so on. This is not a pretty picture but then again Nature; "red in tooth and claw" rarely is.

The only way to make sure that there are enough Humans to evolve into Martians is to have a very high birth rate. So perhaps, as Dr. Strangelove would have it, we should have a wildly disproportionate sex ratio of females to males, in order to have the maximum population growth ("and they should be of a highly stimulating sexual nature" :). So maybe there's something in it for (men) to go to Mars!

Of course we could actually avoid all this trauma (and sex?) by avoiding the natural selection process of Nature by fully understanding the problems we will face. Then we could either, pre-select the individuals who happened to be genetically endowed to survive and reproduce under those conditions or genetically engineer people who can. But that would actually require spending (comparatively little) money on such things as a centrifuge for the ISS to study mammalian reproduction under partial-gee situations. Since our species is not particularly good at planning (climate change anyone?) it appears as if we may be colonizing the old fashioned way; send a lot of people and see who lives.

I think the first polynesians to cross the pacific in their canoes, the first americans to walk across the bering strait and even the first pilgrims to land in New England (1/3 died the first winter) would sympathize.

About 5 years ago I stopped investing in Chinese companies. Why? Because I didn't want to support even indirectly a regime that, without apology, oppressed Tibet and supported the despotic regime of North Korea. I hold them largely responsible for sacrificing millions of my long-separated brothers (yes, I'm ethnic Korean) through starvation and torture simply to keep a "buffer state" in between them and the "capitalist" (ha ha, what irony) South Korea and U.S.

My stance was only hardened by their support, for purely geopolitical/economic considerations (OIL), of Syria and Iran (and, I think Libya). They and Russia have kept those regimes propped up and have made the tragedies in the Middle East even worse (of course America started it but at least we know now that most of us were idiots to be led by one). That's not to mention the authoritarian and despotic regimes that China is supporting in Africa purely for their resources.

Look, I know the West (and especially the U.S.) have done a LOT of bad things but the Chinese don't even make a pretense of things like human rights, even in their own country. As I've said, they've been willing to sacrifice millions for a modicum of security (they could've asked the U.S. and S. Korea if, in return for not letting the Kims return to North Korea from one of their trips to China, we would promise not to put American troops north of the 38th parallel. As if S. Korea would even want American troops on the peninsula once the threat was gone). Now, living in S.E. Asia, I see firsthand how China with its growing power is throwing away treaties and agreements it has signed in order to bully the Vietnamese and Philippines with their ridiculous "cow tongue" shaped demarcation of the seas. They are returning to 19th century "gunboat" diplomacy in the 21 century world.

I fear that as China grows ever stronger, they will continue to discard previous commitments to peace and will literally force their will upon the world. Is that what you want to support? I'm a realist, and I love my gadgets and my improved standard of living brought on by the flood of low-cost Chinese products (often produced with stolen patents and technologies but that's another story) and I'm not quite ready to live without. However, when there's a choice, when you can purchase something that is identical (hopefully) in every way including price to another but one is made in China and one was made in Sweden(?), I hope you'll make the same choice I do.

If China, not the U.S. had the power the NSA has; would any of us have any protection at all? Think of what kind of world that would be to live in. (That's what 1.2 billion people ARE living in).