lajoswinkler

Interesting link. Bull**** laws, complications, etc. http://www.economist.com/blogs/economist-explains/2013/05/economist-explains-12

You're describing PWR, but were referring to BWR. No steam bubbles are allowed in PWR, of course. The temperature is too high and it would be stressful for its zirconium cladding to be constantly heated and cooled by the frothing water. PWR has emergency systems which drop the pressure, allowing the boiling, and the excess tritium laden steam is dumped through the exhaust stack as one of the last resorts while waiting for the pumps to go back online. I think the operators did that at TMI, resulting in very weak release of radionuclides into the environment.

NovaSilisko asked to provide a source for this info. It says in the latest post made by Hadfield on Google+ and is visible in the comment section of the clip.

Whoops, there was an earlier thread. http://forum.kerbalspaceprogram.com/threads/79842-How-cool-is-Chris-Hadfield-Today-is-the-last-chance-to-see-ever Please merge.

I can not believe they're going to remove it. What copyright rules are being breached here? There are hundreds of thousands of videos where people record themselves while covering songs. Whoever is doing this, do they really think you can delete something from the Web in 2014? What a bunch of tight ass twats!

What do you mean by reducing turbine efficiency? Bubbles in boiling water reactor are in the reactor vessel, where the water is. Turbine handles dry steam because there is a separator between the reactor and the turbine. If the separator should fail, droplets are the stuff that errodes the turbine. If the bubbles are large enough, they displace enough water so that the rods can overheat even if the reactor is in a shutdown mode because of the fission products decay. In any way, you don't want them to clog up the fuel bundles. In pressurized water reactor, you don't want them at all, so a pressurizer, using the feedback loop systems, holds the pressure high enough so that no boiling occurs. The negative feedback you're mentioning serves the purpose of removing the threat of sudden power excursion, but can not prevent a meltdown.

It does matter. You are mixing energy and power here. A huge deflagration (fireball) can be so immense that it sets on fire some stuff around it by heat rays, but it is not a detonation. Detonations have much greater powers than deflagrations, though can, and often have, lower energies. An earthquake can release as much energy as as several hundred megaton bombs, and the consequence can be few shaken buildings and spilled tea. That's why it's futile to put such info in the media. Again, power and energy aren't the same thing. In the worst case scenario, you'd get fairly large chunks of it, scattered over the launch area, with most of it crumpled somewhere. That is not a significant problem. Hazmat team would pick the mildly radioactive pieces and use special foams to imobilize any dust. It's enriched uranium, and that isn't very radioactive. It's fissile, but not very radioactive. NERVA which has been working, and is about to reentry, now that would be a disaster. I-131, Cs-137, Sr-90, wow... A disaster. The worst is hard beta, because we're opaque to it. Gamma poorly interacts with organisms, so even those photons have higher energy, much less of them actually manage to ionize the water in our bodies, which is the main reason why ionizing radiation is dangerous. Hard beta is like bullets which explode inside you. So those suits actually help a lot, and in addition, pose an obstacle to radiological contamination.

Chlorine Trifluoride.

Watch "2001: A Space Odyssey" and you will learn. tinyboss, you were faster

I do understant that concept, of course, but I don't understand how you're defending something completely opposite from what my professors of physics were talking to me. Where are those particles if you can't detect them anymore? Do you have one evidence to support your claim that they're "somewhere"? You've written a lot of words, yet none of them explained this. If a photon is ejected from a system, from our reference frame it travels for some time until it hits the target, where it disappears, leaving the target in an excited state. From its reference point, zero time has passed. In every literature I've read it was mentioned that photons appear and disappear, leaving excited states of the target systems they hit. If you're saying that we can't say they disappear because we have no proof of that, that would be fundamentally true, but that's on the order of saying we can't say all Al-27 atoms in cosmos have the same chemical properties because we haven't tested all of them. For all intents and purposes, we can consider them disappearing.

Saturn V had kerosene, LOX and LH2 in separate containers. I don't see how that would cause an extremely devastating explosion capable of dispersing ceramic material encased in steel. This is not a tank full of premixed compounds and it is not SRB which contains solid fuel, which is prone to cracks and violent explosions. The reaction would be violent as the tanks break and spill LOX, there would be a fireball, no doubt about that, but I think some of you are imagining something akin to a small yield nuclear device. That would not happen. When you see a liquid fueled rocket exploding in midair, it is not actually exploding. It's a fireball, a deflagration made by disintegrating structure. If the rocket turns in a wrong direction, the aerodynamic forces are too high and it is ripped to pieces, spilling fuel. This is not a detonation. You can watch what happens with liquid fuel spillage in this famous youtube video.

I don't see the point of glow over bodies without atmosphere, but all of the rest seems very cool. Downloading.

NERVA reactor can't catch fire. Nuclear fuel in all reactors is in the form of oxide, which is a ceramic material with 2865°C melting point, inert to atmosphere. Only nuclear bombs have metallic uranium/plutonium inside, for reasons of critical mass achievement. True, such engine would be a radiological hazard after it has been fired for some time.

I know all about it. It depends on the distance, duration, etc. There sure were some idiotic things (just look at early Chinese tests with their expendable fanatics, charging and chanting), but in essence, watching an atmospheric nuclear test can be done safely. This has to be one of the stupidest posts on KSP forums. Honestly, dude. I was talking about geochemical data which has an extreme scientific value. Introducing a new life form to Mars would render all that useless. A whole planet filled with data, ruined. Killing domestic microbe life would be even worse. It's a wealth of knowledge. If you think that is comparable to corn, then I pity you.

Something like this? This is not dangerous at all. Few kilometres away, gamma rays can't reach you. You can be blinded, but that's what covering your eyes is for. I meant to say a trench, sorry. You can get even closer, where the blast is sufficient to knock you on the ground, but you're safe in a trench. There was at least one test where ordinary citizens participated in the trenches. This is all harmless if you gtfo after the blast... something which many people didn't do. And the microbes would alter the geochemical image of the planet, rendering it useless for research. That would be a crime against the environment on a planetary scale. So many data would be lost.

Wolfram Alpha says autoignition temperature of hydrogen is 536°C, so yes, active engine would release readily flammable hydrogen and it would look like this. Safety flame, or perhaps sparklers, would simply have to be used because liquid hydrogen readily boils off. It is lighter than air and would go up, but explosive mixtures might form nevertheless.

If NERVA uses hydrogen, it's a pretty safe exhaust. Hydrogen has a tiny cross section, meaning it doesn't capture thermal neutrons easily, and it takes two captures to reach tritium, so the amount of tritium expelled would be pretty small, probably negligible. Ignoring the danger from the reactor meltdown and fission product release, the only danger from firing such engine in atmosphere would the the flammability of hydrogen. You'd need to make sure there is a safety flame at the nozzle, so that a great cloud of hydrogen-air mixture doesn't appear and detonate.

I can't define the moment it stopped existing, but I can say I can't detect it anymore, can't I? Instead, I have a bunch of other particles. Let's say that two protons collide at extreme velocities and we get a burst of exotic particles. Where are those protons? They're gone. Nothing is lost except the concept. If you tear down a building, the building is gone. You have a rubble. Mass is conserved (let's ignore the infinitesimally small change), energy is conserved, but the building ceases to exist. It boils down to semantics, really.

Correction: put hypothesis instead of theory. It was safe. The gutter shields you from the initial blast of gamma rays, glasses from blinding light, and you won't be spending enough time there waiting for the fallout to approach. I'd go and watch it anytime, but I'm glad those experiments are a thing of the past.

Existing microbes would not adapt, and using GM ones would be a gross crime against nature and scientific progress. Pristine environment, showing us the geological history of Solar system, and you'd contaminate it with microbes tailored for successful growth? So many information would be lost. We can simulate any kind of condition in the lab, and that's where microbes should stay. This not only it would be stupid, but it would be insanely expensive, too.

This is semantics. Particles do disappear. If I throw a ball into a window, and the ball turns into mushroom, and the window breaks into several roses, mushroom and roses will possess the qualities of the ball (momentum, just to name one), but it isn't a ball anymore. The ball, as a round, rubbery, bouncy object is gone. QM works exactly that way.

People have s gross misunderstanding of the word extremophile, and that's obvious from the original poster's entry post. Those aren't organisms that are capable of withstanding whatever you put in front of them. It means the qualities of their ecological niches are such that organisms we're encountering on regular basis (mesophiles) can't stand it. If you put such organisms in a different niche, they will die. Being an extremophile doesn't mean your niche is wide, and I can't stress that enough. (this is just for the temperatures, there's pressure, pH, salinity, heavy metal content, etc.) We do not have organisms on Earth that could live in space, Mars, Venus, or anywhere else. Why? Because they've evolved to live in their own narrow niches. The only way we could seed another place in space is to genetically engineer an organism, but the problem is that such places are very rare. Interior pockets of Mars, Europa, and other icy bodies, where liquid water exists, are a candidate, but we'd have to investigate those niches and then tailor the organisms for them. Other than that, any attempt is futile and laughable.

Is this a joke? Because those pills have nothing to do with this...

LOL You clearly have little or no knowledge about these things. Energy sources can't be compared only by their power outputs. PV can't be used for base load power in a economically viable and reliable way. It's either coal, fission or hydroelectric. I guess PVs grow on trees. I thought they were made in China, burping insane amounts of pollutants into the environment during the process.

First of all, it's not relatively affordable. It's insanely expensive compared to our common sources. The difference of joules per square metre in orbit and in best ground conditions is not very large. It might look fancy and everything, but this is a pipedream. It's nothing new, it's something the media digs out every decade and people just show how short memory the society has. For the price of such installations in orbit, we could make much more solar power down on Earth. Exactly. I don't even need to calculate the costs. I just know they're insane. They should invest in nuclear energy because base load is what Japan needs. Wind and solar are for peaks and applicable in certain areas and cases, but for peaks only. We can't use anything like that for the base load. Japan doesn't have notable fossil fuel sources, and it invests a great deal of money in high technology. Too bad their society hasn't co-evolved.