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Everything posted by PB666
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Did they give a reason?
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Like yeah, dude, wow, definitely.
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Suprise, suprise . . antihydrogen looks like hydrogen
PB666 replied to PB666's topic in Science & Spaceflight
Spin is a property that is apparent only with observation . . . .Heisenberg tells us that we don't know what spin is until we attempt to observe it. How we observe it is we apply a magnetic field, about half the time it will flip, and emit a photon, the other half of the time it will not. So depending on the magnetic field and a UV tell, we know what the spin is. Charge spin is a magnetic dipole has nothing to do with gravity. For an electron at rest (like never, very very cold place, 0'K) energy and thus gravity is constant irregardless of spin state. When you observe a spin of an electron (all electrons have angular momentum) the angular momentum assumes a quantum state which is some integer function of reduced planks constant. The property that any given electron is -1/2 or +1/2 is 50:50, these are the eigenvalues for the eigenvector that is defined by the Dirac equations. How do we know that all electrons have an angular momentum, the reason we know this is that 1/2 - 1 = -1/2. Because you cannot add or subtract 1 from -1/2 or 1/2, respectively, to get 0 then an electron must always have angular momentum. So for example, if we apply a magnetic field, about 1/2 the time we will get an emission its always the same frequency. If we had a spin of zero, if we flipped electron to spin 1/2 we would see something like E=hv as some fraction of a -1/2 to 1/2 flip. The distribution of eigenvalues would not be 50:50 but something like 25 No hv: 50 smaller hv: 25 most hv. That is not what is observed, the eigenvalues are the observables of the eigenvector. [snipped explanation and beat to the point] It is the interactions between the flowing space-time and energy trapped in various energy systems that create a perception of gravity. If for example, if light requires space-time to flow, then conversely light effects spacetime. This is the way we understand things, C is not just the propogation rate of light, its the field propagation rate of space-time in which light and other massless fields can travel linearly in space-time. Thus if light has some dependency on space-time to travel, then light is also interacting with space-time creating gravity. All fields (e.g. electromagnetic fields, quarks, gluons, leptons, W-bosons, Z-bosons, higgs boson) in space-time contain energy, they all flow, some short distances and others great distances and in this process they warp space time. So that photon that interacted with a disturbance in the field, creates a positron and electron. Both flow in spacetime, there mass determines their inertia. The warp created by one particle interacts via space-time on the members of the pair. if the pair products are traveling slowly, they spend alot of time in the space of the field the integral effect of the interactions is greater. To reduce the integral effect you add more inertia, less time is spent in the field. If you add an infinite amount of inertia (you can't) the effect of local space-time would be minimal, but still present. And basically all particles breakdown into fields, some that flow linearly and others that travel short distances and interact, each interacting with space-time and space-time being influenced as some very small level by the energy. Gravity does not exist; the fictitious nature of gravity was first pointed out by Newton (mysterious force acting at a distance) and confirmed by Einstein. Our perception of space and time is different from the dimensionality of space-time. As stated only our perception of space is static, gravitons are not static, they dart around at c influenced by other fields in space-time and it just so happens that the influence is proportional to the energy. So that the flow of a massive particle (anti-proton or proton) is determined by its inertia and responds to the curvature of spacetime. Electrons (spin = 1, 0 or -1, no charge, its own antiparticle) also are influenced by space-time. If an antiproton wants to not respond to a warping of gravity it needs to spend less time in the space-time field. For that to happen energy needs to be added (either by addition to the system) or conversion of some of its mass to energy. -
Is the launch an actual paying customer or an ESA welfare project.
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With a dual SFR system and one booster faultering MECO simply isn't an option, 'destroyed by extreme aerodynamic forces rings a bell'. Lets say for some reason one SFR is packed improperly, and there is break in thrust on one side then the main engines have to correct all the rotational motion, but in doing that the two engines, now with a offset center of thrust is now creating its own windsheer. About the only thing you could do is to kill release the SFRs and then kill the main engine. One has to beg the question, given that liquid boosters capable of RTLS are available, with ~300 ISP (325 with methane) why exactly is it a good idea to stick with SFRBs on manned launches.
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Confusing, who is going to pay someone to release their payload and then repick it up again. "Hey AO errr ehm yeah thanks for releasing my super duper ION driven Mars lander, yes, hmm, its on Mars at the moment could you, like, go there pick it up and return to Earth." {crickets chirping in the back ground}
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I think the EUS is supposed to share a common bulkhead with SIV upper stage. There is a major difference in the overall design. " The forward bulkhead of the LOX tank formed the aft bulkhead of the LH2 tank. This saved up to 20% of structural weight." this differs from the latticed structure of the EUS.
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Restricted from firing or physically unable to fire?
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Suprise, suprise . . antihydrogen looks like hydrogen
PB666 replied to PB666's topic in Science & Spaceflight
Mmmm, no, here is how spin states work. First there is spin zero Spin Zero. 0 (higgs) boson Spin 1/2 -1/2, + 1/2 (example Leptons and quarks) And example of this is a hydrogen molecule takes 2 s orbitals and creates 1 s-s orbital. Into that one s2 orbital we place two electrons, but QM prevents the placement of two electrons in one orbital with the same spin. So that a hydrogen molecule has an electron with spin 1/2 and spin -1/2. A helium atom has a 1s orbital and a 2s orbital (lowest energy orbitals), it has 4 electrons, we can place an electron -1/2 and 1/2 in the first orbital, then -1/2 and 1/2 in the second. [Stanford has a course in quantum entanglement and electrodynamics online if you want to take them, its designed for retirees] Spin 1 (Photons, Z-boson, W-boson, Gluons) -1, 0, 1 An example of this is that most photons we encounter have a spin of zero, but many photons have circular polarization, this means the polarization is not constant but changes with distance. https://en.wikipedia.org/wiki/Circular_polarization Therefore a photon can either have a positive circular polarization (left handed) a negative circular polarization (right handed) or linear polarization. Circular polarization is the basis of circular dichroism, the study of the bulk secondary structural composition of molecules. For example CD is very good at detecting alpha-helical content in proteins. Spin 3/2 (gravitinos?????) -3/2, -1/2, 1/2, +3/2 Spin 2 (gravitons?). -2, -1, 0, 1, 2 Spin is given as the largest positive charge but the spin can be any negative or positive as long as the absolute value of spin is not greater than the spin number as as long as it an interger variance of that spin number. https://en.wikipedia.org/wiki/File:Standard_Model_of_Elementary_Particles.svg the problem with what you say is this. For energy to be conserved in a closed system, for antiparticles to have negative gravity means that energy has to be added in addition to the energy in their mass. To thing about it like this what you experience as gravity we can do a little gedanken experiment, we are going to remove all the air from the room, now we move you to the north geographic pole, and then we lift you 1 mM above the earth. For the time it takes you to move that 1 mM you are on a suborbital trajectory your mass is following inertial motion. If the earth was a point mass you would have continued to fall and then return to its position exactly where it started. The Hamiltionian for energy SME = SKE - SPE is always conserved. This is the basis for planetary motion as we know it (disregard relativistic perspectives). You are technically not accelerating toward the ground, the electrostatic interactions of the earth are being forced in the direction of your shoes, preventing your shoes from falling. As this is to point out general relativity . . . the point is that the mass of your body is not important, but the energy contained in your body and you mass. If we could keep all your energy in a container, and convert all your mass to energy it would be the same. If we were to convert all your energy to antimatter it would be the same. An excellent example of this is a black hole . . . .technically once matter falls beyond the event horizon we no longer no ifs its mass or energy, in fact we do know that most of the energy in the black-hole is gravimetric in nature, it comes from the conversion of potential energy to kinetic energy. As an object approaches the speed of light, most of its energy is not in its rest mass, but in mass added by the Lorentz variance. You can add energy to an object but at the speed of light it no longer goes into kinetic energy but into mass. But from the perspective of the viewer, he cannot tell from a sterile black hole whether its internal contents are matter, anti-matter or energy . . .a black hole is a quantum singularity. And example of this is we could take an atom, and by focusing powerful lasers (photons have no mass) at a single atom from a very great distance and from all directions (I think it would be something like 40 light years) we could create a black hole. Probably not the easiest way of doing it, but certainly at some very great distance you could transmit enough power on a spot that the energy of the photons will create a black hole. It matters little if they are polarized left or right or linear. If we started with a positron as the single particle, it would be the same, a black hole. The reason for this is a photon is its own antiparticle, which is also true for all bosons except the W-boson, but in a nucleus of an atom both Z and anti-Z bosons coexist, and also true for the higgs boson. So what would happen if, in a black box, I converted all mass to energy, all energy to antimatter of the exact opposite quality and the antimatter had anti-gravity. This would mean that I added some additional energy to the system such that there was a force being applied making it non-intertial. So lets imagine I create anti-lead from lead, the lead would sit on the bottom of the resilient black box, if it was anti-gravity lead it would adhere to the top means I would have to convert entropy to some starting energy (normal lead falls, in falling in converts potential energy to kinetic energy and kinetic energy to heat as it strikes the bottom of the container). This is a problem, because the only way I can practically do that is to reverse time. IOW in our time the lead falls to the bottom as soon as it forms, in reverse time it floats back to the top. This is not how our universe works beyond the point of QM resolution (i.e. about 1/10,000,000,000,000,000,000,000,000,000,000,000,000,000,000 th of a second) and it kind of would imply that if antimatter was also anti-gravitational that it could never persist long enough to be detected. It might be the case that we could see some very fast particles (like antigravitational neutrinos) because of time dilation. -
Hmm, I wonder then why they would not expand the Centuar to accomidate new functions. Yep you are correct. EUS 129,000 kg of propellant. (dont know of any stats for dry weight) DCSS 26,000 kg of propellant (3490 kg of gross weight) for DIV-5metter - 11.83% Centaur 20,830 kg of Propellant (~2250 kg of gross weight) - 9.7%
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This can be contrasted with DIVUS (probably more efficient but for large PLs, very little thrust) [Note NASA little rear bumber 'decorations'] And EUS The interesting thing about these two is the spheroid tanks and the Russian-like lattice between the hydrogen and oxygen tanks. Also not that compared to the RL10B-2 that the RL10-C[3?] on the EUS have very little engine detail.
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The problem with the DC3 is that it is only used in application where it almost has to be used, and keeping engines up an running in an aircraft engine is tedious unless you are going to use it. But my point was not about that, if the 787 is useful say 80 years from now, even in small numbers then one might expect some very well worn 787 to be flying. Its even more abstract than that, because if you look at the types of frame ending damage (for example what happened to some of the last DC6 and 7) they tended to be used by nefarious operators which did the types of things that would end the life of an air-frame. The same can be said about old 737, its generally at the end of their life once they are sold to other parties that the real test of the airframe begins. If you talk about hours and cycles, the primary culprit that takes jet aircraft out of service are the engines. You come to a point where its cheaper to by a new craft (after the current had been fully depreciated anyway) than to buy two (or four) new engines. In the case of a DC8 or earlier craft, you really can't buy them. In the case of other craft (such as 727, 707, and some early 747) many municipalities basically tell you that the planes engines are too noisy or too pollutive to be allowed in and out of a particular airspace. The 727 is an excellent example, it was the fastest of the mid-sized jets, it also used more fuel, its engines were more noisy and in produced more pollution. Eventually it ended up doing package delivery services overnight, and pretty much has been pulled from service. " When the Stage 3 requirement was being proposed, Boeing engineers analyzed the possibility of incorporating quieter engines on the 727. They determined that the JT8D-200 engine could be used on the two side-mounted pylons, but the structural changes to fit the larger-diameter engine (49.2 inches (125 cm) fan diameter in the JT8D-200 compared to 39.9 inches (101 cm) in the JT8D-7) into the fuselage at the number two engine location were prohibitive. "-wikipedia - Boeing 727.
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You do realize they eat the slave for dinner. I wonder why you single him out. He has delusions of grandeur. He is killed in two universes. He obviously has poor choice in women. He ends up being killed by an ex-lover and an unranked specialist in his command (who he should have sent to prison). He built a machine designed to suck the life out of the multiverse and despite that he cannot control diddly in either universe and gets himself killed. In our culture we say his eye is bigger than his stomach (particularly after the empress impales him) I find the series rather interesting in that the different actors have some insight on klingon behavior but none (except the empress from outside the universe) approach an insight into that behavior that would have saved them. Oddly they have the girl-friend of the successor to the Klingon empire but no-one bothered to ask her a very simple question . . . "why the . . . did you attack us in the binary system". As kind of role models they are all poor, because they all have great technical insights but not have the insights on behavior that would allow them to like do James-T-Kirk like manipulations. So now at the end of season 1 we have _ an anti-terran empress free who will probably start her own empire and like start enslaving members of the federation _ a klingon empire who has a human (who had all the knowledge of the previous emperor) that also was involved in 'worm-hole' like travel _ a freed klingon empress that is going to unify the empire. Such leadership. Nice graphics though.
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https://www.wired.com/story/inside-the-cleanroom-where-nasas-new-mars-lander-waits-to-launch/
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Since the PalAnth thread was blocked. https://www.wolfcast.co.uk/all/2018/4/10/arabian-h-sapiens-fossil-key-information
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This I just picked up off reddit science https://www.recode.net/2018/4/10/17220060/facebook-trust-major-tech-company Apparently 2% of people for some odd reason don't trust Tesla, "Elon is going to have eyes in the sky's?"
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But they are separate, BTW, I forgot to add monopropellants are equally vulnerable. So if you are worried about liquids igniting then you best have an electric propulsion system. Monopropellant is generally closer to your payload than the LfOx.
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Its a dirty job but someone has to, but hey i read through the reddit science stuff, most of which is politically biased science.
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The charges for main guns of a battleship make great fodder when the main guns get hit. . . . . .the vulnerability of using solid explosives anywhere.
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The difference principle difference between a solid rocket at and a liquid rocket is that solids are good for boosting and tossing. For fine flight control one requires liquid rockets. The SFRBs on the shuttle provide most of the thrust, but the liquid engines provide most of the dV, but also provide a means of tempering the thrust near MaxQ. Solid only rockets are dangerous for human space flight because of g-load limitations of biological organisms. Solids - Boost and weight tossing. Liquids - acceleration x time and control. If you thought about it like this . .if a solid rocket is free, and all you have to do is pay for structural connection to the core then it cost almost nothing to the core to boost the core up and then toss the SFRB. But as it turns out SFRB thrusters might be cheaper, but not cheaper then RTLS liq boosters that can be reused. So if you pretend the RTLS liq booster is free, then there is no reason ever to use an SFRB.
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Neither does a 787, in fact compared to a bullet train its IAS is actually similar. Since it never gets to Mach Speed, and when it gets close its essentially at 30,000 feet, about 1/3 surface pressure. Niether does it experience the windshere of going in and out of a tunnel at 150+ m/s. But you would know about the difference of both vehicles if you had experienced both, but you haven't. And there is not much in the normal structural loading on a carbon fiber hull of a 787 that would significantly age it. Maybe in 40 years, but again judging by some of the DC3 in service currently (i.e. built in 1935), it would generally have to require some unusual service that would cause a 787 hull to experience the type of stress that would be useful (determine the limits of that design). I would seriously doubt anyone would put the kind of money down on a 787 if its expected life was less than 30 years. BFR is to be designed and completed in 5 . . .its would be rather useless. It means that SpaceX needs to do some stress testing on their own, for example a sounding rocket with lower than expected tolerance in order to see what stress can be observed. ------ I should add to the above that a rocket passing Mach 1 has a boundary layer that separates from the craft the rejoins down the craft, as the speed increases that layer moves down the side of the craft until it surpasses the engines. Its a primary reason you don't want to linger near Mach speed. This is very similar to what happens when a fast train passes into a tunnel. As the train approached the tunnel a pressure gradient builds at the face of a tunnel, which dissipates as it travels into the tunnel, and pressure declines on the skin.
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Well certainly not diesel, low fuming kerosene would be tolerable. But just to clean it you would need some kind of volatile chemical and that in and of itself is a problem. If you were going to weld in space you would at least have to have it clean enough to flux the metal. Its very difficult, short of sanding or flaming to clean oil off metal. There are other solutions, such as using prefit brackets that can snuggly fit and snap together in an unwelded manner. Once these are attached false interior walls can be placed and welded. Here's the problem, there must be some sort of welding work done to create a dock port or hatch. That means recycling means a mandatory work in space. . . . . . or the tanks itself is built with a docking port installed.
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Well if you are going to use a 787 as a model, a craft that climbs to 8000 feet before the cabin undergoes pressurization, and gantly climbs over 20 minutes to its cruising altitude with a craft that at maxq traveling 500 m/s nearly vertical to a complete. A typical descent rate is 3 natical miles per 1000 feet of elevation, essentially 100 meters per 1.8 km traveled. . . . .at 250 knots FL100 trans limit that occurs about 125 m/s and on 10s of meters per second vertical change versus 100s of meters per second, that is a fairly major difference in the rate of pressure change. There is almost no chance at all that a 787s pressure hull will ever fail, there could be other damages that LOAF but gently climbing in and out per standard climbout and descents are not going to be that cause. If you [snip] looked it up, you would find that the stretching of a shinkansen as it moves into a tunnel is considerably more than 787 and notable by the passengers, the vibrational forces per unit of cabin structural mass are also alot greater than a 787 during flight, 787 runs on air, the trains runs on rails. Despite what you bias tells you, a bullet train faces the types of forces per unit of structure mass more comparable to a rocket.
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They drop at about 5-10 feet per mile east bound. SpaceX does not, as of yet have a port facility in Port of Brownsville which is like 12 miles from their launch site. You could potentially launch from a retired derrick (not quite as many as there used to be). That sea lane shoots out from the Port Isabel jetties due east into the Gulf of Mexico, that is the last Seaway in the continental United States. Its not used like the galveston ship channel, but during the summer you see tankers lined up about 10 miles offshored anchored waiting to get to the port of Brownsville. In fact currently there is not even a road going to BC suitable to carry a BFR, let alone a road going to the Port that could carry a BFR. Boca chica hiway is essentially a park road. So, when are we going to see a SpaceX facility at the Port of Brownsville, not to mention, expansion of the port requires an environmental impact study which takes years to complete. The ends of the Port Isabel jetties the water is 65 feet deep (20 meters). . . . .tropical marine gulf, and going and coming out of their its has some of the steepest swells in a gulf going trip. I don't see this as a major problem, but during the summer the wind can blow 15 to 25 knots constantly, only quietening for a few hours in the morning and this can go on for days, offshore the wind dies down considerably, their launch site experience some of the highest constant winds . . .in mid summer these tend to blow strait up from Mexico (why S.Texas is semi-arid). Downrange is east, so they will have protracted launch delays due to heavy winds along the coast. OTOH in the winter a cold-front can pass over, and short of a cloud line and a modest shift of wind its hardly noticeable. In august and september it might actually be easier to launch off-shore from BC.
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Even if they choose to launch in the mid-pacific, they still have range issues. Don't forget maritime laws apply to everyone, so if they planned to launch from the mid-pacific then they have to provide their own range officers. I should also point out that for communication satellites that are LEO (high LEO) they don't really want (need) equitorial launches. The satellites need to be able to cover ranges of latitude relative close to Earths surface. This requires as stated above dozens of orbital planes.