softweir

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About softweir

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  1. 50 km long cave discovered on moon

    Now I know why I felt a disturbance in the force, as if a million spelunkers cried out in frustration: "but *I* want to go there!"
  2. There are two types of fairing: one type is in the Structural Tab and can't be released - they are for building custom fuselages, and you don't want bits of fuselage dropping off mid-flight! The other type is in the Decouplers tab and can be released as you would expect.
  3. Why does Hydrogen peroxide is so toxic?

    There is a complex chemical process used to generate hydrogen peroxide. You can read about it On Wikipedia. Hydrogen peroxide (H2O2) is highly unstable: that extra oxygen atom is not a stable addition to a water molecule! For instance, when it comes in contact with copper and some other metals it spontaneously decomposes into oxygen and water, releasing so much energy that the water is converted to superheated steam. (This is used by some of those "rocket jetpacks" that you can find details about online - H2O2 is pumped through a copper mesh, and the resulting steam and oxygen can be used as a propellant. This can, of course, be very dangerous.) Also, when it comes in contact with some hydrocarbons (such as vehicle fuels) then it will spontaneously catch fire; that is, there doesn't need to be any spark to set the mixture alight. If there is enough fuel and H2O2 then the fire can be extremely hot: this is because the H2O2 generates heat as it decomposes, and more heat is generated when the fuel burns. Even when there is no fire or other emergency, H2O2 will slowly decompose, releasing oxygen. It can release enough oxygen that this can be hazardous to health, if it is in an enclose area. Not only that, but the buildup of oxygen in the air can make normally stable materials burn readily, so the tiniest spark can trigger a fire or explosion. In addition, when H2O2 comes in contact with living tissue it releases the excess oxygen, creating highly reactive free radicals that can damage and destroy the living tissue. The effect on fish and other waterborne organisms can be devastating: it kills them all! So: if H2O2 gets spilled on a road then there is a very serious risk of poisoning waterborne life or a major fire starting. It is imperative that Action is taken to prevent fuel coming into contact with the H2O2 spill Action is taken to prevent people touching the spill, as it can damage skin Barriers are set up to prevent it flowing into drains that lead to waterways It is neutralised using a suitable material. There are dry powders which safely absorb the H2O2, allowing it to be swept up. If there is no danger to waterways, then it can be washed into a drain using a very large volume of water to dilute it to safe concentrations Action is taken to repair the roadway, as H2O2 corrodes the tar used in many road surfaces (The exact order of actions depends on risks at a given spill site. For instance, if there is already a fuel spill when firefighters reach the scene then the first priority is to cover the spill with a suitable foam or dry powder.) Very dilute H2O2 is sometimes used in very small quantities as an antiseptic on minor cuts and abrasions. It is sufficiently oxidising that it kills almost all bacteria, while at the same time there are enzymes in the blood that can neutralise small amounts, preventing it causing deep damage to the wound. However, this practice is now frowned upon in much of America and Europe, as it does damage superficial tissues, which in turn can seriously slow down the healing process - and the damaged tissues can act as food for any bacteria that get into the wound later on. Instead of using H2O2, it is much better to use a sterile gauze to clean a wound and then dress it with a sterile bandage. If there is some special need to use antisepsis (such as the wound being open, the patient having some illness which predisposes them to infection, or the agent causing the wound being thought to be contaminated) then iodine is preferred: it damages tissues much less readily than hydrogen peroxide does, while being a very effective bactericide.
  4. How does Gravity exist?

    Depends. A candle, yes, that is true - the wax has such low melting & vapourisation points that the plasma loses heat very rapidly. The candle also conducts away a lot of heat. You end up with a spherical puffball of vapourised wax! A match, however, acts differently. If there are no air currents to mess things up and the match is held perfectly still, then the plasma can't lose heat except by radiation, and plasma is not a very efficient black-body radiator! The wood is not a good conductor of heat, so the combustion doesn't lose heat that way. The centre of the sphere of plasma is almost perfectly insulated by layers of decreasingly hot air that can't conduct the heat away. However, combustion continues: oxygen molecules diffuse in to the plasma, and combustion products diffuse out, exchanging heat with the oxygen molecules as they go so the zone of combustion barely loses any. As the gasses diffuse, so the oxygen mixes with superheated combustants and reacts with them, generating more heat. You end up with a concentration gradient of superheated combustants at the centre and cold air outside. The "fire" is perfectly spherical, intensely hot, emits no visible light, and slowly consumes the entire match. If disturbed by an air current then there is a very sharp "pop" as the plasma mixes with fresh air and combusts, and then the fire goes out as heat is carried away by the moving air. Such fires are hard to detect. No smoke is generated, as any particulates formed would diffuse more slowly than the gasses, and so would stay in the hottest zone until they evaporated and combusted. Though IR is emitted, it is at a shorter wavelength than is normal for gravity-sourced fires, so beyond the range of most IR detectors. Combustants are perfectly oxidised, so CO monitors would fail to pick them up. This would be a serious danger on on any space station that is less than perfectly-maintained. A short-circuit could create combustion that would be almost undetectable. The danger is that the sphere of combustion would grow large enough that it could become supercritical, expanding rapidly until it turned into an explosion, or at least caused critical equipment failure. (Sorry, very off-topic!)
  5. You are assuming these people will be working on KSP. However, though Squad makes KSP, Squad <> KSP. There is nothing preventing them from making other games. An alternative is that they have an Acting Lead Developer, but that person doesn't have experience outside of Squad in that field and is making it up as they go along learning on the job. This is very common in Startup companies in game development, but it isn't a long-term sustainable situation in a growing company: it is too easy for an inexperienced person to set up faulty development models that then need to be reworked. We've seen some comments in The Daily Kerbal over the years which suggest they have had to rework their development paths repeatedly. It is common practice for one of the more experienced developers to fill the lead developer role in an informal capacity, and then for a more experienced lead developer to come in to streamline the production of more complex games. One important skill for a Lead Developer worth their pay is to make good guesstimates of how long it will take to do any given job, and decide who is best suited for that job. This enables them to dovetail work more efficiently than a less experienced person can, thus making sure everything ends up being done on time and with nobody hanging around for somebody else to finish their job. The more games a person has worked on, the better the guesstimates! At some point, the Acting Lead Developer will use the experience he gained in that role plus the experience he gained under a professional Lead Developer to get a job elsewhere as Assistant Lead Developer, and if s/he has the chops will go on to be Lead Developer for somebody, somewhere.
  6. Do you launch / revert / re-launch? Any launch to rendezvous algorithm can only guess at your rocket's characteristics and how it will launch, and therefore can only guess at what time to launch. In order to deal with this, a full simulation has to be performed: NASA and co use powerful computers to do this, we have to use a trick to get the right "guess": Launch the rocket using Launch to Rendezvous/Plane. Mechjeb will make its best guess and will probably get it wrong, but it will save data on the characteristics of the rocket that will allow it to do a better job next time. This step is the "simulated" launch. Revert to launch. Repeat the launch without changing any launch profile settings or rocket loadout. (This is essential. The characteristics Mechjeb saved will only be valid if the launch profile and loadout are identical. If you change anything then you must go back to Step 1.) Mechjeb will use the saved rocket characteristics to get a very-nearly spot-on rendezvous or launch-to-plane. I hope this helps!
  7. Agreed. Getting started would be a huge effort, and a lot of machines and essential components would need to be sent to whichever body one is talking about. One might be able to build some simple machines on the moon by sending the electronics and other precision components, along with a small robot to assemble them and a small oven to construct larger components by fusing regolith. The fused regolith wouldn't be very strong, but in that low gravity strength is much less of an issue than on Earth so it might be sufficient. Building a rocket... Nope. Not without many, many billions of dollars and many, many decades, even centuries of effort. We would have to start by sending a huge amount of startup infrastructure, and it would take a lot of trial and error to build new machines from scratch using the materials available. It is quite likely that a rocket manufactury on the moon would never be completely self-sufficient, and would depend on some refined materials being sent from Earth: the infrastructure needed for producing the dopes used in semiconductor manufacture (for instance) is huge! Considering the very unlikely hypothesis that we could do it, then there would be advantages. There is no ecology on the moon to destroy, so we could mine and plunder what we needed without any concerns for the morality of wiping out species or fears for poisoning ourselves. Without a rain cycle, waste would stay where it was dumped. Solar power would be available in huge amounts, just by laying out large arrays of solar panels. And the products of a moon-based infrastructure would be in an ideal gravitational situation to be sent to much of the rest of the solar system, helping to start infrastructures elsewhere.
  8. [1.2] RCS Build Aid v0.9.1

    It is rather counterintuitive!
  9. A Claw Wheel

    What are you trying to achieve? Wheels that lock a craft down while landed?
  10. [1.3] RealChute Parachute Systems v1.4.4 | 01/06/17

    The advantage of using a mini-cfg is that it will stay even if a new version of RealChute is downloaded, saving effort repeatedly! A neat trick is to put any such cfg's in a separate folder within gamedata, where it is easier to keep track of them.
  11. SpaceX Discussion Thread

    Since it has to be robust enough to provide more acceleration during an emergency than it carries during launch, then it would inevitably be at least robust enough to survive. But why put it in the first stage interstage? Why try to save the second stage? The second stage has no facilities that would be useful during a launch emergency, and during an emergency is just dead weight, making a ring LES needlessly heavy to launch every time. Why not have it as part of the second stage interstage, just below the capsule?
  12. SpaceX Discussion Thread

    NASA are concerned about hypergolics - the safety procedures surrounding them are complex, detailed, and rigorously documented and adhered to. But there are no reliable alternatives.
  13. Auto-Extending Nozzle?

    (My emphasis.) Unfortunately, the problem with the idea lies right there in the bolded phrase. If the nozzle extension improves ISP, then the upward acceleration it experiences due to the pressure of gasses inside it will prevent it dropping - would have to be forced down. If it is inert enough to drop, then it "weighs" more than the extra force it returns from the gas stream. I like the idea of a "collapsible cup", but some other mechanism would be needed to extend the nozzle! I have no idea if there are any mechanisms that could do that and deal with the extremes of heat, vibration and pressure experienced by rocket nozzles.
  14. SpaceX Discussion Thread

    I watched it, a few hours after the launch. Have another look?
  15. is "Kerman" a family name after all ?

    IIRC, HarvesteR once mentioned that "Kerman" is an honorific, like "mister" or "san".