As I understand, the Little Boy (gun barrel) concept is pretty straightforward if you have the material. You just take two nearly critical masses and shoot them into each other at a velocity sufficient to create a critical mass faster than the increasing reaction rates can blow the mass apart. I don't think the Little Boy design was even tested before Hiroshima...unless you count the scientists at the University of Chicago with their atomic pile in the basement. This design is apparently pretty dirty and has a very limited yield.
The compressed sphere/cylinder concept, as you said, is much harder. Collapse of the mass into a critical density has to be almost perfectly uniform or it fizzes out. It sounds to me like that probably happened in North Korea. I seriously doubt they were trying for a 1/2 kiloton bomb. In designing the HE shells to collapse the fissile material, they reportedly test them on hollow metal blanks the size and shape of the warhead. The metal blank is expected to be evenly shrunk to a fraction of it's original size, but not deformed in any way. It's so precise that they use hundreds of detonators, because the explosive burns to slow to create even pressure from a single detonation point, and all the wires are the same length, to avoid even minor changes in capacitance from delaying any one detonator.
BS. First of all, there are no Mars missions on the books of the scope of JWST. By far the biggest, the Mars Surface Laboratory is projected to come in around $1 billion. JWST is a roughly $4 billion project. The plans for Mars are fairly well established through 2013, and there's nothing in there that doesn't already have it's own money. In fact, the only candidate of similar scale is the Jupiter Icy Moons Orbiter, which has already been postponed indefinitely (read "cancelled").
Second, if you thought the astronomers raised a fuss when O'Keefe originally cancelled the Hubble servicing mission, you literally have seen nothing yet. Researchers seem to be almost unanimously agreed that however much they value the Hubble, they'll shoot it down themselves if it threatens to steal one penny from the JWST. There's plenty left that Hubble can explore, but it's biggest discoveries are probably done. To go deeper, they need JWST.
Third, JWST is already deep into the design phase and some parts are already being made, such as the sunshade and spacecraft frame. If Griffin drops the JWST now, all that cost and effort is wasted.
But perhaps you were thinking of the Moon program? Basically the same story as Mars. The Orion CEV and the Ares I are scheduled to be completed by 2012. The LSM and Ares V development will commence in earnest somewhere around that time and fly by 2018. All this is budgeted, too, mostly from money freed up by the shuttle program. If they even tried to sneak money away from the science budget to support this, they're going to face the wrath of astronomers around the world.
Human lives can be lost over just about anything a person deems is worth risking it for. People can lose their lives camping, skiing, driving to work in the morning, eating (see: Heimlich manuever. see also: obesity), or by just plain growing old. People can lose their lives helping other people (firefighters, police). People can lose their lives exploring mountains, caves, or the Great Barrier Reef (RIP Steve Irwin). People can sure as heck lose their lives exploring space. Death is a part of life. It's foolish to flaunt it, but it is equally foolish to waste your life being terrified of any little chance of death.
What politicians and the general public should not accept is if NASA were to lie to their employees about the risks of what they do. Frankly, I don't think it's possible to convince well-educated engineers, scientists, and pilots working in a field where several percent of their colleagues have died on the job that there are not significant risks to their job.
In addition to your comments, a quick browsing of the site suggests that this plan really only looks at the cost of going to the moon...not the cost of maintaining reliable low earth orbit access. That's the whole point of developing two distinct vehicles. One does heavy lifting for big projects like this (and furthermore could offer a platform for Mars exploration), the other gets people up and and down. This "grassroots" movement mixes the roles. It ends up that every time you go to the ISS you're paying to launch a vehicle with a 75 tonne capacity instead of one with a 20 tonne LEO capacity.
Essentially they are proposing just a scaled down Ares V, but NASA would then have to split the load differently. The big payload is the lander and the earth departure stage, carried by the Ares V. The little payload is the Orion crew capsule, carried by the Ares I. Now they're proposing to lose 50 tonnes of LEO capacity, meaning the overall architecture that NASA has already started contracting for (Lockheed is moving ahead on the Orion) may need to be reworked, tossing some of the design that's already been done out the window.
I'm not saying it's not worth considering. There are some very good points to it. For example, not having to develop a 5 segment solid rocket booster. It also looks freaking cool. But on their other side, our LEO launch capability 10 years from now will 40% lower than if we go ahead with the Ares I and Ares V concepts. Even is NASA agrees with their cost and feasibility, they may still choose to pay the extra bit to support the long term goals that have been proposed.
Not really related to Alienware, but I'm actually in the middle of building a new system right now, and have been struggling with three issues while picking components:
Reviewer paradigm: Since so many reviewers depend on the manufacturer's for their samples, they can't piss off the supplier with a bad review on a bad product. Therefore negatives are always cleverly worded, or they do the "ample ashtrays" trick and focus on the useless things that are done right. Professional reviews become almost worthless (mind you, consumer reports doesn't bother comparing evaluating geek parts like mobo's...just general consumer products, so they're worthless in this endeavor, too). On the other hand, try relying on amatuer reviews like Newegg's product feedback, and you can bet that a big chunk of the people who ever bothered to come back and write a review are the one's who had problems, so there's a paradigm shift the other way from that method of research.
Lack of experience: There's a few good exceptions like Toms Hardware and Anandtech, but it seems most sites don't actually test the products they review, they just compare specs. Toms Hardware would be great, but they can't review everything, and they only do one sample of each for a limited duration, so quality control and durability issues don't show up. Amatuer reviews like Newegg shoppers are also usually close to worthless in this regard, because they're usually from kids who just unpacked their new video card or whatever and are so excited to talk about it they just had to go write a review immediately.
Tainted Samples: I can't say for sure whether this is happening, but I've heard accusations of it, and comparing amatuer to professional reviews supports the accusations. It seems manufacturers are often (understandably) careful to send reviewers pre-tested and known to be perfect samples. In particular I noticed that motherboard reviews from the professionals all tended to be very positive and everything worked out of the box. Consumer reviews, however, showed most products to be very mediocre: plenty of DOA's, abnormally warm chips while others report cool running, and buggy BIOS'es...lot's of buggy BIOS'es in fact.
It does make me wonder how much of this Alienware has to go through in deciding what components to offer in their builds.
1.) There might really be life there that we're missing. If we "seed" Mars, we taint any future observations. We might even end up overwhelming it (eg, non-native invasive species).
2.) What do you send? As others have noted, the environment on Mars is extremely hostile to life as we know it. We could spend half a billion dollars sending a capsule with some fancy extremophiles there only to have them all die.
3.) Assuming they survive, in a radically different environment, they may no longer be helpful. Instead of photosynthesizing CO2 for O2, for instance, they may decide they'd rather lie dormant until disturbed by a human host, turning him into a evil zombie that can only be stopped from spreading by wiping out all intelligent life from the galaxy (btw, mod +1: Halo reference).
Your question has been asked before. In fact, NASA has an oversight person titled the "Planetary Protection Officer" whose job is to ensure that probes which we send to Mars and other planets are as free from bacteria and spores as possible, and for sample returns like from the Moon or Stardust mission, make sure there is no threat of some unexpected, unstoppable contamination that might kill us all (or even just millions of people).
These are some of the more interesting ones currently operating or scheduled to come online before 2010. As you see, the different space agencies actually operate quite a few space-based observatories, each with different capabilities and goals. When any one of them is decommissioned, they lose a little bit of their overall capability, but that's life. Nobody made as much fuss, for example, when the Compton Gamma Ray Observatory was deorbited, despite its significant contributions to cosmology.
Also, the astronomers who were upset about the idea of Hubble being abandoned were almost universally agreed that if push comes to shove, they would much rather give up the Hubble than have any more features cut from the JWST.
600 million people were supposed to simultaneously jump on July 20th to alter the earths orbit to prevent global warming. Only after the fact did anybody bother to tell us this could lead to our extinction. Oh no!
Once again, a post suggesting that astrophysics research basically stops without the Hubble.
It is true that the particular wavelengths it images are largely unique among current and proposed space observatories, but those are certainly not the only wavelengths of interest. The justification of the high cost of the James Webb Space Telescope comes from the fact that no other observatory has the deep infrared capability or sensitivity to examine early galaxies in the detail that JWST will. In fact, JWST will actually build on what Hubble revealed with its ultra deep field survey. Basically, Hubble (and Spitzer) showed that infrared is the most interesting part of the spectrum inaccessible from the ground. Of course, there's also the x-ray, microwave, and ELF bands, all useful for astronomy, which the Hubble can not observe, but other projects do.
Furthermore, the Hubble's capabilities aren't really unique. There is significant overlap in the infrared capabilities between it, JWST, and several smaller space observatories, and even ground observatories in the near IR range. Obviously, the Hubble's visible wavelength observations are redundant with the many ground-based observatories, some with better resolution than the Hubble due to adaptive optics. Not to mention data collected by the Hubble will continue to be analyzed and even reused for additional projects long after Hubble is de-orbited.
Don't get me wrong, the Hubble is a great tool, probably the most versatile observatory available. It will be missed, and I personally think it's worth the risk of one extra shuttle mission to get another five years out of it. However, the cost of continuously maintaining it compared to the additional science it can offer versus investing in new observatories is hard to justify when we only give NASA $16 billion a year, and there's a huge political pressure (and plenty of slashdotters) that would have the shuttle grounded as soon as possible.
An "internet" of redundant space telescopes is a marvellous idea. NASA would surely love to have a fleet of Hubbles at their bidding, but the internet and astronomy, both functionally and economically, can't even be compared as apples to oranges. It's more of an apple orchard to Faberge egg comparison.
Because Hawking radiation scales inversely to the area of the event horizon, the Hawking radiation from anything but extremely small black holes (which we don't even know actually exist) is negligible and far below what we have the ability to detect. It is literally less than the background radiation of space.
For practical purposes, the grandparent is correct, if a little simplified.
You may find it interesting though, that if small black holes actually do exist (they would have to be incidental products of the Big Bang), we may be able to detect their last moments of evaporation by Hawking radiation as x-ray/gamma ray bursts. Some researchers are plan to look use data from one of NASA's upcoming x-ray observatories to look for such flashes that can not be attributed to other known sources.
For example, according to the US government, I grew up in a household well below the poverty level (ie, we were part of that 35% figure in the GP's linked article). My parent's owned our house and two cars. As far as the basic human needs go, we were never genuinely wanting for food, water, or shelter...or medical care. We had a TV, a computer, and internet service. heck, we even had a basketball hoop and a 4-wheeler. Of course, my parents were very smart about their finances, too. We weren't one of those families that spends $200 a week on microwave dinners.
Well, I guess "Gee whiz, we went there" is hard to value scientifically and altruistically, but I know a lot of people who spend thousands of dollars just so they can say "Gee whiz, we went there" for a vacation when they could've just bought a couple post cards.
Not that I think of mankind exploring the solar system in person as merely vacation or a distraction for our collective societal mind. However, I do think that such purpose justifies the investment at least as much as the $billions spent every year on music, movies, art, and fictional reading, etc. In the case of space, though, those of us interested in seeing it for the sake of seeing it have to vote or lobby our tax dollars in that direction rather than simply going to Amazon and buying a CD, and we have to respect our neighbors if more of them choose to vote or lobby tax dollars away from NASA.
As far as human space travel not being a distraction for the collective societal mind, I don't think humans in space has any less value for the ultimate growth of our understanding of the universe compared to that offered by robotic missions than the experiences of a tourist in a foreign city does compared to a post card. There are definitely limits to what cameras and spectrometers can provide us in either case.
The main difference, of course, is the price of a holiday versus a space program; those pesky launch costs you refer to. I really hope the current track we're on leaves us in good position to further our exploration over the next 10, 20, and 30 years to go beyond low earth orbit and the moon, but the cost/benefits will be coupled with the idealistic dreams and other factors in determining how far we go how fast.
I won't bother re-iterating others thoughts on the proposal of exploration as a survival tactic, but I think that's a worthy angle, too.
Would they change where they send him to play? Probably not. Current planning has been conducted based on images taken my the Mars Odyssey and Mars Global Surveyor probes. The best images of the area from those probes are around 1/4 the resolution (1-2 meters/pixel) if I remember right. Still, they show the major features and led to the decision to try to reach the crater.
If you look at the path the rover took from Endurance crater to Victoria, it's pretty much a straight line. The goal for the last 6 months was just to get there. The rover has been running for 10 times as long as needed to be considered a successful mission, and almost 3 times as long as even the most optimistic estimates (they had to get a special budget approval for the operations team after the end of the first year...after two planned-for operational budget extensions).
Even if they had more confidence in the continued longevity of Opportunity, they probably still wouldn't have changed the course much. First, Duck Bay looks like a potentially excellent entrance to the crater, so it's a good place to begin observations. Second, Victoria is half a mile across (1.5 miles around). In a little under 3 years, they've accrued a total of about 5 miles of driving. The further around they start their approach, the longer they have to wait for really detailed pictures that will allow them to pick the true points of interest.
This picture is way cool. I remember way back when they first landed and the MGS caught a picture of the rovers. It was single-spectrum (B&W), and you could see 3 or 4 darker grey pixels that were labeled as the rover, half a dozen or so pixels labeled as the lander, and a sparse string of very slightly darker pixels that seemed to nearly line up labeled as the rover tracks. In this picture you can actually see what direction it's pointed and just barely make out the white stripe of the camera mast.
Nice. But getting past the joke for anyone who may be confused:
If you observe a field of 100 stars and find that 16 of them have planets, then it is not unreasonable to speculate on the extension that 16% or so of all stars have planets. Thus from a galaxy with 200 billion stars, billions of them may have planets.
Furthermore, none of this precludes the possibility that more stars may have planets than don't.
Unfortunately, however, Worldcom didn't really have more cash than their independent auditors found, but that's another story.
The article said these findings were based on 7 days of observations, using the transit method. In this method, the planet passes in front of the star, causing a very small, but sudden and periodic drop in the brightness of the star. Presumably, they don't claim to have a candidate unless they see multiple dimming events. If so, the longest possible orbit they could have observed is 7 days, meaning the planets are extremely close to their stars. Even their moons would be inhospitable.
However, as another poster pointed out, these systems may also harbor smaller planets in more favorable orbits. In fact, some researchers believe that smaller rocky worlds can only form with the assistance of disturbances created by the gas giants.
In contrast, other researchers are skeptical that planets can form at all in the inner regions of the galaxy because of the high star density. Even if they did, they might not be able to harbor life because of all the radiation from said stars.
As another poster pointed out, however, we don't necessarily know the limits of conditions that life may form. This is getting a rather fanciful, but perhaps high-temperature silicon-based rock monsters are real, like Season 4, episode 7 where Kirk fought the lava man with the Abe Lincoln avatar (just kidding, I made that up...or did I?).
No. A G-suit essentially increases the pressure in your veins in your extremeties by squeezing to prevent blood from collecting in those areas, leading to blackout because the place where you need the blood is your brain. Astronauts, to the best of my knowledge, do not currently wear G-suits (accelerations not high enough to need them). Also a crash couch only protects against short-duration accellerations or uneven pressure caused by the funny shape of the human body. Once you run out of travel, you see the same acceleration as the bolts holding the couch to the floor.
It does not matter if you are floating in a liquid. If you are accellerating, then any given little incremental chunk of you is experiencing a force proportional to its mass and the accelleration. Filling you with a pressurized goo at 1,000 psi may sound like a good idea if you can assure that it is genuinely isostatic, but it's not actually supporting anything. It's just eliminating pressure points. Your body parts will still reach orbit neatly sorted by density. If you want you can test the theory by sticking an angler fish or other deep sea life in a pressurized tank on a rocket sled and brake it really hard at the end of it's run.
The science fiction authors were wrong on this one.
What I really want to know...As does alot of the world not in the united states but still grounded under it's definition of right and wrong is why can't a foreign self governing nation control its own airspace and space space. If I built a spy satellite and orbitted it over the united states I would be a terrorist and bombed in seconds. Why the difference for china?
First, as stated in the article, pretty much no one in the Department of Defense is surprised by the Chinese attempt to counter our satellites. It was bound to happen. The Russians have done it, too. Heck, the Russians shot down one of our U2's (a plane is a little more in your face, though). In fact, the Iraqis used a Russian-built system during the ground war in 2003 that was designed try to jam our GPS satellites (ironically, it was destroyed by GPS guided bombs). The DoD is not making the fuss out of this you pretend they are.
Second, no sane person debates China's or any other self-governing nation's right to control their own airspace (see above regarding the U2 piloted by Francis Gary Powers). Remember that P3 Orion that a Chinese MiG crashed into a couple years back and made an emergency landing on Chinese soil? Part of the fuss about that, and I think the reason they actually returned the plane to us without first reverse engineering every single black box inside it, is because the plane had been so careful to stay outside of Chinese airspace until it was seriously damaged in the collision.
Third, there are no claims on space. China has no "space space." The United States has no "space space." According to UN treaties and accords as well as some de facto understandings, basically once you get above that 100 km mark you are free from governance by the laws of any particular country you happen to be over.
Fourth, the United States is not the only nation that operates spy satellites. Off the top of my head, I can think of quite a few others, and I assume most if not all of those orbit over the United States (ie, they are not geosynchronous). For example, I recall seeing news blurbs about the launch of military satellites by the US, Russia, China, Japan, Italy, India, France, the UK, and Israel.
Your post is completely off base and quite misleading.
Furthermore...it's not like a Lieutenant Colonel has authority to launch weapons anyways.
While it may not require as high level authorization as it does in the US (I don't know, I'm sure their procedure is pretty secretive), I'd be willing to seriously bet that no one man in the USSR had authority to initiate a launch. Even Kruschev or Gorbachov or whoever would've had to have support from his generals to relay the order.
So this Lt. Col. is having a bad day and decides "Gee, the timing patterns and numbers of these launches are nothing like they told us to expect, but I'm not gonna be the guy who didn't finish destroying the world if the US starts it," and he escalates the warning. From there, some really important general goes "Oh crap! Are you sure?" to which our hero says "Umm...not really, there's only five and they were launched at weird intervals." At this point all the generals have a 2 minute pow-wow (The missiles take 20-30 minutes to reach their targets...they have something like 15 minutes to decide in order for launch to take place before missiles targeted against their own silos reach them). They choose to wait and see if there's more launch signatures and if anything appears on radar before making a decision that will guarantee missiles are heading their way. If there are more launch signatures, they have plenty of time to launch. If there aren't but the missiles are real, there will be plenty of infrastructure left over from so few warheads to authorize further launches. The order goes out for the missile crews to go on standby, all ready bombers to launch, and for the president to get in his bunker, but no launches take place.
Don't get me wrong, this guy did good, but it sounds like we were way closer back in 1962 over Cuba than in this case.
More data helps deal with random error. If there is a systemmatic error you can constrain the mean all you want with extra data, but it might still be a long ways off.
Say you're interested in the average global temperature 20,000 years ago. You figure out a method for estimating the temperature. For example, looking at the the ratio of O16 to O18 in the ice, since water formed with O18 evaporates at higher temperatures. From this you might get an increase of 1 degree, with a standard deviation of 1 deg. Then you say with something like 68% confidence the actual mean was 0 and 2 deg. However, your benefactor says that's not good enough, especially because the present day observed temperature trend over the past 100 years is about 1 deg; the same error described by your confidence interval.
So then you take more data and analyze it and find a mean of 0.9 deg (there we see that random error affecting the first measurement) with a standard deviation of 0.25 deg. Now we can say with something like 98% confidence (2 stdev's) that the change was between 0.4 and 1.4 degrees and your benefactor is happy.
Then some jerk from another university does a different study using tree growth rings (note: I don't think this method is actually useful for such long timescales, but we'll pretend it is for the discussion) and comes up with an 0.9 deg decrease with a standard deviation of 0.25 deg. What happened?
One of you is wrong. Somebody has a systemmatic error. You may not have read the ratio of O16 to O18 accurately. Or it may be that there was a greater difference between the temperature at the poles and the equator (note there are no trees at the poles and not much ice at the equator...these hypothetical methods can not be directly compared) in the past than at the present, and that caused the results of the two methods to differ. Perhaps your samples were tainted during handling. Etc.
Furthermore, none of that precludes Stephen Hawking building a time machine and sending back weather stations to a variety of locations in the past whic find the 20,000 year temperature trend to actually globally be 10 degree (Oh no we're screwed) or -10 degree (quick, burn more coal, it's an ice age!); showing that both methods have major systemmatic errors.
The OP had a legitimate question and I'm not exactly sure of the answer or how much dissenting data there is (I have seen some). However, I do know much more of the debate is over systemmatic error than random error. For example, when someone claims a study by Exxon is wrong, they are usually claiming a systemmatic error (intentional or accidental). I would say at least as much of the debate is not about errors, but the degree of human influence versus natural effects, which is why many people have brought up points like the receding polar ice caps on Mars over the last decade and the increase in solar activity over that past 100 years.
But, for the love of science, when do we get the rest of the data from the mission -- you know, the stuff that is, like, going to alter the way we view Mars? Is the public never going to see these results?
First off, I debate the implication that pictures of the surface have no value. There is a reason why almost every space probe we've launced bothers with the bulk and weight of at least some sort of camera, much less a big one. At the very least, visible light is the format our eyes are used to looking at and good for picking out spots of interest based on geometry, color, and shadowing. Things as mundane as color can differentiate types of rock, for example, and apparent texture yields clues as to the degree of weathering that occurs in a location (ie, how the atmosphere affects the surface, from your post). Also, if I understand right, the stereo cameras on the Express give them the ability to create a 3-D map of the surface, so simultaneously they're getting topography data (certainly that has value, although I don't know what large scale errors might be inherent to the method) without the added weight/power requirement of a radar.
Besides, far infrared, microwave, x-ray, or broadband spectrometers are not magic. They only give us details that visible light doesn't. What you use depends on what you're looking for.
Secondly, if you want to see all the data returned from the mission, you probably aren't going to find it on the ESA public website. There's a lot of data. Gigabytes so far if I understand right. Even the extremely well-published Mars rovers, the hyper-photo-active darlings of NASA, only have data from the visible/near-visible light instruments posted regularly. I think if you want any really comprehensive set of data, especially raw data, you need to formally request it.
Also, related to the last point, I've heard the ESA is somewhat protective of their data. Not surprisingly, since their tax money built the Express, they probably want to give their scientists the first crack at interpreting it and publishing the papers that will change the way we view Mars.
Anyway, you may have already seen it, but here is a pile of Mars Express-related images from ESA. It looks to me like a lot of them are screenshots of textured 3-D models based on multiple exposures.
I assume you're not talking about electrodynamic tethers, which work against the earth's magnetic field to produce an acceleration, but rather a rotating tether that dips into the atmosphere? In either case, they are only theoretically well understand. NASA has had a couple inconclusive experiments with the former, and the latter is conceptually simple but no one has ever tried tackling the practical challenges of building one.
There's a bigger problem though: All that energy has to come from somewhere and it comes out of the tether's orbit (compared with a space elevator where it comes from the earth's rotation). The result is that as your satellite goes up, your tether falls out of the sky. Also, I've read that the stress from the centripetal accelleration of the payload still exceeds what can be accomplished with present day materials.
I prefer the tether idea as a means of launching probes out of low earth orbit and into deep space. Couple two masses together, find a way to accelerate them (perhaps counterotate them against two other masses using a solar powered motor), then let go and watch them fly way.
That's exactly what I was thinking while looking at those pictures.
Half of the purpose of having neat wiring is maintainability (in addition to aesthetics, air flow, and just plain keeping crap out of the way of other things). That setup is almost as unmaintainable as a wall draped in spaghetti. I at least hope they either have good documentation kept up to date to match the small fortune and abundant time they spent on zip-ties or else have both ends of their cables labeled so they know which cable to yank once they do cut all those zip ties, because you aren't going to trace those out by hand.
I guess if your system is perfect and you have no need to ever replace equipment or expand, this is fine, but for the rest of us, give us some service loops and removable wire clips.
I wonder what happens to the power cell when you try to turn your laptop 180 degrees with this thing spinning 20,000 rpm. You're completely reversing the momentum of the turbine, and unlike in a jet engine, it happens rather quickly and rather frequently.
As they are still obviously in development of a benchtop prototype, I further wonder if that thought has crossed their minds.
I'm thinking longevity here, not safety. Precession would create a high load on the shaft and bearings.
All correct, but I want to add in that since the the rate of evaporation is inversely proportional to mass, small black holes evaporate extremely quickly. For example, in the wikipedia entry on Hawking Radiation, I found sample calculations showing that black hole with a mass of about 200,000 kilograms would evaporate in about 1 second! Anything smaller would evaporate much more quickly (imagine the curve y = 1/x as a rough approximation of the rate). At LHC, the mass is obviously far lower (I'm not sure how much equivalent mass is contributed by kinetic energy from the collider, but it seems to me the total is only a few hundred AMU), so for all practical purposes, evaporation happens instantly.
I think the energy yield would actually be rather freaky (we wouldn't want to be anywhere near it). The largest nuclear bomb ever detonated had a yield of 50 megatons, and probably only converted a few grams of tritium and plutonium into energy. In the 1 second case, that's 200 tonnes of matter! The yield would be a million times greater than the biggest nuclear bomb ever made.
Obviously, we don't want to be anywhere near such an event. The garbage disposal method someone else proposed (a few posts up) is pure fantasy. If micro black holes exist, they might be detectable as they "blow up" like this.
On the other hand, I've read that string theory may affect this, as somehow extra dimensions would slow down Hawking radiation. I have no idea how much, but the final burst would still occur extremely rapidly.
Actually, it would evaporate before it could even encounter another particle. In fact, even if it did encounter another particle, it couldn't encounter more at a rate faster than it evaporates. Hawking radiation is inversely proportional to mass.
The distance it would fall before radiating into nothingness is on the order of a proton radius.
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As I understand, the Little Boy (gun barrel) concept is pretty straightforward if you have the material. You just take two nearly critical masses and shoot them into each other at a velocity sufficient to create a critical mass faster than the increasing reaction rates can blow the mass apart. I don't think the Little Boy design was even tested before Hiroshima...unless you count the scientists at the University of Chicago with their atomic pile in the basement. This design is apparently pretty dirty and has a very limited yield.
The compressed sphere/cylinder concept, as you said, is much harder. Collapse of the mass into a critical density has to be almost perfectly uniform or it fizzes out. It sounds to me like that probably happened in North Korea. I seriously doubt they were trying for a 1/2 kiloton bomb. In designing the HE shells to collapse the fissile material, they reportedly test them on hollow metal blanks the size and shape of the warhead. The metal blank is expected to be evenly shrunk to a fraction of it's original size, but not deformed in any way. It's so precise that they use hundreds of detonators, because the explosive burns to slow to create even pressure from a single detonation point, and all the wires are the same length, to avoid even minor changes in capacitance from delaying any one detonator.
BS. First of all, there are no Mars missions on the books of the scope of JWST. By far the biggest, the Mars Surface Laboratory is projected to come in around $1 billion. JWST is a roughly $4 billion project. The plans for Mars are fairly well established through 2013, and there's nothing in there that doesn't already have it's own money. In fact, the only candidate of similar scale is the Jupiter Icy Moons Orbiter, which has already been postponed indefinitely (read "cancelled").
Second, if you thought the astronomers raised a fuss when O'Keefe originally cancelled the Hubble servicing mission, you literally have seen nothing yet. Researchers seem to be almost unanimously agreed that however much they value the Hubble, they'll shoot it down themselves if it threatens to steal one penny from the JWST. There's plenty left that Hubble can explore, but it's biggest discoveries are probably done. To go deeper, they need JWST.
Third, JWST is already deep into the design phase and some parts are already being made, such as the sunshade and spacecraft frame. If Griffin drops the JWST now, all that cost and effort is wasted.
But perhaps you were thinking of the Moon program? Basically the same story as Mars. The Orion CEV and the Ares I are scheduled to be completed by 2012. The LSM and Ares V development will commence in earnest somewhere around that time and fly by 2018. All this is budgeted, too, mostly from money freed up by the shuttle program. If they even tried to sneak money away from the science budget to support this, they're going to face the wrath of astronomers around the world.
Human lives can be lost over just about anything a person deems is worth risking it for. People can lose their lives camping, skiing, driving to work in the morning, eating (see: Heimlich manuever. see also: obesity), or by just plain growing old. People can lose their lives helping other people (firefighters, police). People can lose their lives exploring mountains, caves, or the Great Barrier Reef (RIP Steve Irwin). People can sure as heck lose their lives exploring space. Death is a part of life. It's foolish to flaunt it, but it is equally foolish to waste your life being terrified of any little chance of death.
What politicians and the general public should not accept is if NASA were to lie to their employees about the risks of what they do. Frankly, I don't think it's possible to convince well-educated engineers, scientists, and pilots working in a field where several percent of their colleagues have died on the job that there are not significant risks to their job.
In addition to your comments, a quick browsing of the site suggests that this plan really only looks at the cost of going to the moon...not the cost of maintaining reliable low earth orbit access. That's the whole point of developing two distinct vehicles. One does heavy lifting for big projects like this (and furthermore could offer a platform for Mars exploration), the other gets people up and and down. This "grassroots" movement mixes the roles. It ends up that every time you go to the ISS you're paying to launch a vehicle with a 75 tonne capacity instead of one with a 20 tonne LEO capacity.
Essentially they are proposing just a scaled down Ares V, but NASA would then have to split the load differently. The big payload is the lander and the earth departure stage, carried by the Ares V. The little payload is the Orion crew capsule, carried by the Ares I. Now they're proposing to lose 50 tonnes of LEO capacity, meaning the overall architecture that NASA has already started contracting for (Lockheed is moving ahead on the Orion) may need to be reworked, tossing some of the design that's already been done out the window.
I'm not saying it's not worth considering. There are some very good points to it. For example, not having to develop a 5 segment solid rocket booster. It also looks freaking cool. But on their other side, our LEO launch capability 10 years from now will 40% lower than if we go ahead with the Ares I and Ares V concepts. Even is NASA agrees with their cost and feasibility, they may still choose to pay the extra bit to support the long term goals that have been proposed.
Not really related to Alienware, but I'm actually in the middle of building a new system right now, and have been struggling with three issues while picking components:
Reviewer paradigm: Since so many reviewers depend on the manufacturer's for their samples, they can't piss off the supplier with a bad review on a bad product. Therefore negatives are always cleverly worded, or they do the "ample ashtrays" trick and focus on the useless things that are done right. Professional reviews become almost worthless (mind you, consumer reports doesn't bother comparing evaluating geek parts like mobo's...just general consumer products, so they're worthless in this endeavor, too). On the other hand, try relying on amatuer reviews like Newegg's product feedback, and you can bet that a big chunk of the people who ever bothered to come back and write a review are the one's who had problems, so there's a paradigm shift the other way from that method of research.
Lack of experience: There's a few good exceptions like Toms Hardware and Anandtech, but it seems most sites don't actually test the products they review, they just compare specs. Toms Hardware would be great, but they can't review everything, and they only do one sample of each for a limited duration, so quality control and durability issues don't show up. Amatuer reviews like Newegg shoppers are also usually close to worthless in this regard, because they're usually from kids who just unpacked their new video card or whatever and are so excited to talk about it they just had to go write a review immediately.
Tainted Samples: I can't say for sure whether this is happening, but I've heard accusations of it, and comparing amatuer to professional reviews supports the accusations. It seems manufacturers are often (understandably) careful to send reviewers pre-tested and known to be perfect samples. In particular I noticed that motherboard reviews from the professionals all tended to be very positive and everything worked out of the box. Consumer reviews, however, showed most products to be very mediocre: plenty of DOA's, abnormally warm chips while others report cool running, and buggy BIOS'es...lot's of buggy BIOS'es in fact.
It does make me wonder how much of this Alienware has to go through in deciding what components to offer in their builds.
A couple reasons:
1.) There might really be life there that we're missing. If we "seed" Mars, we taint any future observations. We might even end up overwhelming it (eg, non-native invasive species).
2.) What do you send? As others have noted, the environment on Mars is extremely hostile to life as we know it. We could spend half a billion dollars sending a capsule with some fancy extremophiles there only to have them all die.
3.) Assuming they survive, in a radically different environment, they may no longer be helpful. Instead of photosynthesizing CO2 for O2, for instance, they may decide they'd rather lie dormant until disturbed by a human host, turning him into a evil zombie that can only be stopped from spreading by wiping out all intelligent life from the galaxy (btw, mod +1: Halo reference).
Your question has been asked before. In fact, NASA has an oversight person titled the "Planetary Protection Officer" whose job is to ensure that probes which we send to Mars and other planets are as free from bacteria and spores as possible, and for sample returns like from the Moon or Stardust mission, make sure there is no threat of some unexpected, unstoppable contamination that might kill us all (or even just millions of people).
FYI (my apologies for the gratuitous use of wikipedia)
Hubble Space Telescope
Spitzer Infrared Space Telescope
Chandra X-ray Observatory
Infrared Space Observatory
Corot Space Telescope
MOST Telescope
Astro-F Space Telescope
Swift Gamma Ray Telescope
Kepler Space Telescope
SOHO
These are some of the more interesting ones currently operating or scheduled to come online before 2010. As you see, the different space agencies actually operate quite a few space-based observatories, each with different capabilities and goals. When any one of them is decommissioned, they lose a little bit of their overall capability, but that's life. Nobody made as much fuss, for example, when the Compton Gamma Ray Observatory was deorbited, despite its significant contributions to cosmology.
Also, the astronomers who were upset about the idea of Hubble being abandoned were almost universally agreed that if push comes to shove, they would much rather give up the Hubble than have any more features cut from the JWST.
600 million people were supposed to simultaneously jump on July 20th to alter the earths orbit to prevent global warming. Only after the fact did anybody bother to tell us this could lead to our extinction. Oh no!
Stupid people are funny.
Once again, a post suggesting that astrophysics research basically stops without the Hubble.
It is true that the particular wavelengths it images are largely unique among current and proposed space observatories, but those are certainly not the only wavelengths of interest. The justification of the high cost of the James Webb Space Telescope comes from the fact that no other observatory has the deep infrared capability or sensitivity to examine early galaxies in the detail that JWST will. In fact, JWST will actually build on what Hubble revealed with its ultra deep field survey. Basically, Hubble (and Spitzer) showed that infrared is the most interesting part of the spectrum inaccessible from the ground. Of course, there's also the x-ray, microwave, and ELF bands, all useful for astronomy, which the Hubble can not observe, but other projects do.
Furthermore, the Hubble's capabilities aren't really unique. There is significant overlap in the infrared capabilities between it, JWST, and several smaller space observatories, and even ground observatories in the near IR range. Obviously, the Hubble's visible wavelength observations are redundant with the many ground-based observatories, some with better resolution than the Hubble due to adaptive optics. Not to mention data collected by the Hubble will continue to be analyzed and even reused for additional projects long after Hubble is de-orbited.
Don't get me wrong, the Hubble is a great tool, probably the most versatile observatory available. It will be missed, and I personally think it's worth the risk of one extra shuttle mission to get another five years out of it. However, the cost of continuously maintaining it compared to the additional science it can offer versus investing in new observatories is hard to justify when we only give NASA $16 billion a year, and there's a huge political pressure (and plenty of slashdotters) that would have the shuttle grounded as soon as possible.
An "internet" of redundant space telescopes is a marvellous idea. NASA would surely love to have a fleet of Hubbles at their bidding, but the internet and astronomy, both functionally and economically, can't even be compared as apples to oranges. It's more of an apple orchard to Faberge egg comparison.
Because Hawking radiation scales inversely to the area of the event horizon, the Hawking radiation from anything but extremely small black holes (which we don't even know actually exist) is negligible and far below what we have the ability to detect. It is literally less than the background radiation of space.
For practical purposes, the grandparent is correct, if a little simplified.
You may find it interesting though, that if small black holes actually do exist (they would have to be incidental products of the Big Bang), we may be able to detect their last moments of evaporation by Hawking radiation as x-ray/gamma ray bursts. Some researchers are plan to look use data from one of NASA's upcoming x-ray observatories to look for such flashes that can not be attributed to other known sources.
Here here.
For example, according to the US government, I grew up in a household well below the poverty level (ie, we were part of that 35% figure in the GP's linked article). My parent's owned our house and two cars. As far as the basic human needs go, we were never genuinely wanting for food, water, or shelter...or medical care. We had a TV, a computer, and internet service. heck, we even had a basketball hoop and a 4-wheeler. Of course, my parents were very smart about their finances, too. We weren't one of those families that spends $200 a week on microwave dinners.
Well, I guess "Gee whiz, we went there" is hard to value scientifically and altruistically, but I know a lot of people who spend thousands of dollars just so they can say "Gee whiz, we went there" for a vacation when they could've just bought a couple post cards.
Not that I think of mankind exploring the solar system in person as merely vacation or a distraction for our collective societal mind. However, I do think that such purpose justifies the investment at least as much as the $billions spent every year on music, movies, art, and fictional reading, etc. In the case of space, though, those of us interested in seeing it for the sake of seeing it have to vote or lobby our tax dollars in that direction rather than simply going to Amazon and buying a CD, and we have to respect our neighbors if more of them choose to vote or lobby tax dollars away from NASA.
As far as human space travel not being a distraction for the collective societal mind, I don't think humans in space has any less value for the ultimate growth of our understanding of the universe compared to that offered by robotic missions than the experiences of a tourist in a foreign city does compared to a post card. There are definitely limits to what cameras and spectrometers can provide us in either case.
The main difference, of course, is the price of a holiday versus a space program; those pesky launch costs you refer to. I really hope the current track we're on leaves us in good position to further our exploration over the next 10, 20, and 30 years to go beyond low earth orbit and the moon, but the cost/benefits will be coupled with the idealistic dreams and other factors in determining how far we go how fast.
I won't bother re-iterating others thoughts on the proposal of exploration as a survival tactic, but I think that's a worthy angle, too.
Would they change where they send him to play? Probably not. Current planning has been conducted based on images taken my the Mars Odyssey and Mars Global Surveyor probes. The best images of the area from those probes are around 1/4 the resolution (1-2 meters/pixel) if I remember right. Still, they show the major features and led to the decision to try to reach the crater.
If you look at the path the rover took from Endurance crater to Victoria, it's pretty much a straight line. The goal for the last 6 months was just to get there. The rover has been running for 10 times as long as needed to be considered a successful mission, and almost 3 times as long as even the most optimistic estimates (they had to get a special budget approval for the operations team after the end of the first year...after two planned-for operational budget extensions).
Even if they had more confidence in the continued longevity of Opportunity, they probably still wouldn't have changed the course much. First, Duck Bay looks like a potentially excellent entrance to the crater, so it's a good place to begin observations. Second, Victoria is half a mile across (1.5 miles around). In a little under 3 years, they've accrued a total of about 5 miles of driving. The further around they start their approach, the longer they have to wait for really detailed pictures that will allow them to pick the true points of interest.
This picture is way cool. I remember way back when they first landed and the MGS caught a picture of the rovers. It was single-spectrum (B&W), and you could see 3 or 4 darker grey pixels that were labeled as the rover, half a dozen or so pixels labeled as the lander, and a sparse string of very slightly darker pixels that seemed to nearly line up labeled as the rover tracks. In this picture you can actually see what direction it's pointed and just barely make out the white stripe of the camera mast.
Nice. But getting past the joke for anyone who may be confused:
If you observe a field of 100 stars and find that 16 of them have planets, then it is not unreasonable to speculate on the extension that 16% or so of all stars have planets. Thus from a galaxy with 200 billion stars, billions of them may have planets.
Furthermore, none of this precludes the possibility that more stars may have planets than don't.
Unfortunately, however, Worldcom didn't really have more cash than their independent auditors found, but that's another story.
The article said these findings were based on 7 days of observations, using the transit method. In this method, the planet passes in front of the star, causing a very small, but sudden and periodic drop in the brightness of the star. Presumably, they don't claim to have a candidate unless they see multiple dimming events. If so, the longest possible orbit they could have observed is 7 days, meaning the planets are extremely close to their stars. Even their moons would be inhospitable.
However, as another poster pointed out, these systems may also harbor smaller planets in more favorable orbits. In fact, some researchers believe that smaller rocky worlds can only form with the assistance of disturbances created by the gas giants.
In contrast, other researchers are skeptical that planets can form at all in the inner regions of the galaxy because of the high star density. Even if they did, they might not be able to harbor life because of all the radiation from said stars.
As another poster pointed out, however, we don't necessarily know the limits of conditions that life may form. This is getting a rather fanciful, but perhaps high-temperature silicon-based rock monsters are real, like Season 4, episode 7 where Kirk fought the lava man with the Abe Lincoln avatar (just kidding, I made that up...or did I?).
No. A G-suit essentially increases the pressure in your veins in your extremeties by squeezing to prevent blood from collecting in those areas, leading to blackout because the place where you need the blood is your brain. Astronauts, to the best of my knowledge, do not currently wear G-suits (accelerations not high enough to need them). Also a crash couch only protects against short-duration accellerations or uneven pressure caused by the funny shape of the human body. Once you run out of travel, you see the same acceleration as the bolts holding the couch to the floor.
It does not matter if you are floating in a liquid. If you are accellerating, then any given little incremental chunk of you is experiencing a force proportional to its mass and the accelleration. Filling you with a pressurized goo at 1,000 psi may sound like a good idea if you can assure that it is genuinely isostatic, but it's not actually supporting anything. It's just eliminating pressure points. Your body parts will still reach orbit neatly sorted by density. If you want you can test the theory by sticking an angler fish or other deep sea life in a pressurized tank on a rocket sled and brake it really hard at the end of it's run.
The science fiction authors were wrong on this one.
First, as stated in the article, pretty much no one in the Department of Defense is surprised by the Chinese attempt to counter our satellites. It was bound to happen. The Russians have done it, too. Heck, the Russians shot down one of our U2's (a plane is a little more in your face, though). In fact, the Iraqis used a Russian-built system during the ground war in 2003 that was designed try to jam our GPS satellites (ironically, it was destroyed by GPS guided bombs). The DoD is not making the fuss out of this you pretend they are.
Second, no sane person debates China's or any other self-governing nation's right to control their own airspace (see above regarding the U2 piloted by Francis Gary Powers). Remember that P3 Orion that a Chinese MiG crashed into a couple years back and made an emergency landing on Chinese soil? Part of the fuss about that, and I think the reason they actually returned the plane to us without first reverse engineering every single black box inside it, is because the plane had been so careful to stay outside of Chinese airspace until it was seriously damaged in the collision.
Third, there are no claims on space. China has no "space space." The United States has no "space space." According to UN treaties and accords as well as some de facto understandings, basically once you get above that 100 km mark you are free from governance by the laws of any particular country you happen to be over.
Fourth, the United States is not the only nation that operates spy satellites. Off the top of my head, I can think of quite a few others, and I assume most if not all of those orbit over the United States (ie, they are not geosynchronous). For example, I recall seeing news blurbs about the launch of military satellites by the US, Russia, China, Japan, Italy, India, France, the UK, and Israel.
Your post is completely off base and quite misleading.
Furthermore...it's not like a Lieutenant Colonel has authority to launch weapons anyways.
While it may not require as high level authorization as it does in the US (I don't know, I'm sure their procedure is pretty secretive), I'd be willing to seriously bet that no one man in the USSR had authority to initiate a launch. Even Kruschev or Gorbachov or whoever would've had to have support from his generals to relay the order.
So this Lt. Col. is having a bad day and decides "Gee, the timing patterns and numbers of these launches are nothing like they told us to expect, but I'm not gonna be the guy who didn't finish destroying the world if the US starts it," and he escalates the warning. From there, some really important general goes "Oh crap! Are you sure?" to which our hero says "Umm...not really, there's only five and they were launched at weird intervals." At this point all the generals have a 2 minute pow-wow (The missiles take 20-30 minutes to reach their targets...they have something like 15 minutes to decide in order for launch to take place before missiles targeted against their own silos reach them). They choose to wait and see if there's more launch signatures and if anything appears on radar before making a decision that will guarantee missiles are heading their way. If there are more launch signatures, they have plenty of time to launch. If there aren't but the missiles are real, there will be plenty of infrastructure left over from so few warheads to authorize further launches. The order goes out for the missile crews to go on standby, all ready bombers to launch, and for the president to get in his bunker, but no launches take place.
Don't get me wrong, this guy did good, but it sounds like we were way closer back in 1962 over Cuba than in this case.
More data helps deal with random error. If there is a systemmatic error you can constrain the mean all you want with extra data, but it might still be a long ways off.
Say you're interested in the average global temperature 20,000 years ago. You figure out a method for estimating the temperature. For example, looking at the the ratio of O16 to O18 in the ice, since water formed with O18 evaporates at higher temperatures. From this you might get an increase of 1 degree, with a standard deviation of 1 deg. Then you say with something like 68% confidence the actual mean was 0 and 2 deg. However, your benefactor says that's not good enough, especially because the present day observed temperature trend over the past 100 years is about 1 deg; the same error described by your confidence interval.
So then you take more data and analyze it and find a mean of 0.9 deg (there we see that random error affecting the first measurement) with a standard deviation of 0.25 deg. Now we can say with something like 98% confidence (2 stdev's) that the change was between 0.4 and 1.4 degrees and your benefactor is happy.
Then some jerk from another university does a different study using tree growth rings (note: I don't think this method is actually useful for such long timescales, but we'll pretend it is for the discussion) and comes up with an 0.9 deg decrease with a standard deviation of 0.25 deg. What happened?
One of you is wrong. Somebody has a systemmatic error. You may not have read the ratio of O16 to O18 accurately. Or it may be that there was a greater difference between the temperature at the poles and the equator (note there are no trees at the poles and not much ice at the equator...these hypothetical methods can not be directly compared) in the past than at the present, and that caused the results of the two methods to differ. Perhaps your samples were tainted during handling. Etc.
Furthermore, none of that precludes Stephen Hawking building a time machine and sending back weather stations to a variety of locations in the past whic find the 20,000 year temperature trend to actually globally be 10 degree (Oh no we're screwed) or -10 degree (quick, burn more coal, it's an ice age!); showing that both methods have major systemmatic errors.
The OP had a legitimate question and I'm not exactly sure of the answer or how much dissenting data there is (I have seen some). However, I do know much more of the debate is over systemmatic error than random error. For example, when someone claims a study by Exxon is wrong, they are usually claiming a systemmatic error (intentional or accidental). I would say at least as much of the debate is not about errors, but the degree of human influence versus natural effects, which is why many people have brought up points like the receding polar ice caps on Mars over the last decade and the increase in solar activity over that past 100 years.
First off, I debate the implication that pictures of the surface have no value. There is a reason why almost every space probe we've launced bothers with the bulk and weight of at least some sort of camera, much less a big one. At the very least, visible light is the format our eyes are used to looking at and good for picking out spots of interest based on geometry, color, and shadowing. Things as mundane as color can differentiate types of rock, for example, and apparent texture yields clues as to the degree of weathering that occurs in a location (ie, how the atmosphere affects the surface, from your post). Also, if I understand right, the stereo cameras on the Express give them the ability to create a 3-D map of the surface, so simultaneously they're getting topography data (certainly that has value, although I don't know what large scale errors might be inherent to the method) without the added weight/power requirement of a radar.
Besides, far infrared, microwave, x-ray, or broadband spectrometers are not magic. They only give us details that visible light doesn't. What you use depends on what you're looking for.
Secondly, if you want to see all the data returned from the mission, you probably aren't going to find it on the ESA public website. There's a lot of data. Gigabytes so far if I understand right. Even the extremely well-published Mars rovers, the hyper-photo-active darlings of NASA, only have data from the visible/near-visible light instruments posted regularly. I think if you want any really comprehensive set of data, especially raw data, you need to formally request it.
Also, related to the last point, I've heard the ESA is somewhat protective of their data. Not surprisingly, since their tax money built the Express, they probably want to give their scientists the first crack at interpreting it and publishing the papers that will change the way we view Mars.
Anyway, you may have already seen it, but here is a pile of Mars Express-related images from ESA. It looks to me like a lot of them are screenshots of textured 3-D models based on multiple exposures.
I assume you're not talking about electrodynamic tethers, which work against the earth's magnetic field to produce an acceleration, but rather a rotating tether that dips into the atmosphere? In either case, they are only theoretically well understand. NASA has had a couple inconclusive experiments with the former, and the latter is conceptually simple but no one has ever tried tackling the practical challenges of building one.
There's a bigger problem though: All that energy has to come from somewhere and it comes out of the tether's orbit (compared with a space elevator where it comes from the earth's rotation). The result is that as your satellite goes up, your tether falls out of the sky. Also, I've read that the stress from the centripetal accelleration of the payload still exceeds what can be accomplished with present day materials.
I prefer the tether idea as a means of launching probes out of low earth orbit and into deep space. Couple two masses together, find a way to accelerate them (perhaps counterotate them against two other masses using a solar powered motor), then let go and watch them fly way.
That's exactly what I was thinking while looking at those pictures.
Half of the purpose of having neat wiring is maintainability (in addition to aesthetics, air flow, and just plain keeping crap out of the way of other things). That setup is almost as unmaintainable as a wall draped in spaghetti. I at least hope they either have good documentation kept up to date to match the small fortune and abundant time they spent on zip-ties or else have both ends of their cables labeled so they know which cable to yank once they do cut all those zip ties, because you aren't going to trace those out by hand.
I guess if your system is perfect and you have no need to ever replace equipment or expand, this is fine, but for the rest of us, give us some service loops and removable wire clips.
I wonder what happens to the power cell when you try to turn your laptop 180 degrees with this thing spinning 20,000 rpm. You're completely reversing the momentum of the turbine, and unlike in a jet engine, it happens rather quickly and rather frequently.
As they are still obviously in development of a benchtop prototype, I further wonder if that thought has crossed their minds.
I'm thinking longevity here, not safety. Precession would create a high load on the shaft and bearings.
All correct, but I want to add in that since the the rate of evaporation is inversely proportional to mass, small black holes evaporate extremely quickly. For example, in the wikipedia entry on Hawking Radiation, I found sample calculations showing that black hole with a mass of about 200,000 kilograms would evaporate in about 1 second! Anything smaller would evaporate much more quickly (imagine the curve y = 1/x as a rough approximation of the rate). At LHC, the mass is obviously far lower (I'm not sure how much equivalent mass is contributed by kinetic energy from the collider, but it seems to me the total is only a few hundred AMU), so for all practical purposes, evaporation happens instantly.
I think the energy yield would actually be rather freaky (we wouldn't want to be anywhere near it). The largest nuclear bomb ever detonated had a yield of 50 megatons, and probably only converted a few grams of tritium and plutonium into energy. In the 1 second case, that's 200 tonnes of matter! The yield would be a million times greater than the biggest nuclear bomb ever made.
Obviously, we don't want to be anywhere near such an event. The garbage disposal method someone else proposed (a few posts up) is pure fantasy. If micro black holes exist, they might be detectable as they "blow up" like this.
On the other hand, I've read that string theory may affect this, as somehow extra dimensions would slow down Hawking radiation. I have no idea how much, but the final burst would still occur extremely rapidly.
Actually, it would evaporate before it could even encounter another particle. In fact, even if it did encounter another particle, it couldn't encounter more at a rate faster than it evaporates. Hawking radiation is inversely proportional to mass.
The distance it would fall before radiating into nothingness is on the order of a proton radius.