PB666

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That first wiki page is kind of whack. Theoretically you could have a small rest matter traveling at very close to the speed of light. Not arguing this, but I would point out that all of our efforts to detect dark matter have failed in the lab. All efforts to detect dark energy have failed. As far as unknown aspect of gravity, I have to repeat gravity as a force is a faux force, Einstein pointed out that via observation that you cannot discriminate the quality of gravity from centripedal acceleration, -another know faux force. If I am in an evacuated chamber and throw a ball at a few cm per second from our perspective, just like being in a centrifuge the ball will fall, but once it leaves my hand no force is applied, it is in an intertial reference frame. The center of the earth in a newtonian context is applying force to the layers of earth above it all the way to the chamber and the evaculated chamber is being pushed up, the ball is not accelerating the chamber is. Yes mass curves space time, but so does energy. And yet the construction of space-time itself is almost a complete mystery. Possible explanations are 1. High rest mass low non-mass energy particles (good example would be black holes or fragments of super-dense matter 2. Low rest mass high energy particles. neutrinos for example 3. Variation in the manner in which average-out space-time interactions occur at the quantum level. 4. An official dark particle.

BTW mountains and trees do the same thing, just they don't generate power. Everest is blocking alot of wind, I propose we chop it down. When you drill oil and gas out of the ground, it makes the ground shallower, or stripmine a coal mountain you increase wind speed, so everything balances out. And of course all those CO2 emissions that generate warmer air over the altantic and increase the risk for higher intensity hurricanes. You compare all the DeltaE from turbines with a single unit change in category hurricane, the turbine DeltaE is trivial. Get a clue.

What you need to do is imagine the difference between collective observations and non-collective observations to comprehend gravity. Everything in this universe that we measure is the result of comparing interactions of collectives. For example, has anyone ever measure the gravitational interaction of two photons of light passing really close to each other? And yet photons propogate through the milieu of quantum space-time. As they are passing each other is it possible to measure quantum gravitational attacking between two cells of quantum space-time. The answer for several different reasons is no. Imagine you lived in a quantum world, now imagine that in this quantum world their were kingdoms each with a history and a future. Now imagine you could travel between the kingdoms and measure their statistics, (size, length of existence, energy). But if you probed the kingdoms you might find that the measures in each were strange, to gain a sense of the kingdom of what the king values, and his measures of space and time may differ from yours or the next guy. So it is in the collective of observations you come to understand how the kingdoms statistics relates. But in that case you have no real idea about measures of size or length of time; this best you could arrive at is a probabilistic estimate that has some parameter of power as a governing feature (in our case energy associated with field intensities) In the quantum world quantum space-time has a fleeting size and temporal existence. But we can measure the effects of the collective, but we are not of a scale that we can make sense of the singular object of space-time. Gravity is the measurement of the collective, the resolution of quantum events to a measurable collective is something we only presume to understand. Quantum space-time is an unfolding that begins from the big-bang itself, it is the oldest operational force of the universe, through which all other forces can exist. The universe according to this quantum space-time changed markedly from the singularity, though inflation to expansion. It is not for us to tell quantum space-time what it is by divinating and guessing, it is for us to discover what it is by better observations of the universe.

The thread starts the discussion. Since then it has evolved. Gravity is a perception from space-time perspective. The perception is created by the structural interactions of quantum space-time. These interactions defy dimensional logic (as they are based on the probabiiistic and not discrete measurement) and only can perceived in their accumulation. The universal gravitational constant may not be constant, but if it is not constant, then there are things about quantum space-time that we do not understand. That would not be shocking since we have as yet to measure quantum space-time. If we divorce the discussion from dark matter and instead refer it to an unknown source of gravitation surrounding galaxies then we do not need to make matter appear or disappear.

Alright lets just devolve this discussion into the real world and pull it out of fantasy. Presumbably the chixulub impactor was ovoid or spherical shape, and largely a silico-metalic bolloid that had a density comparable to a planet inner solar system satellite. It was probably an inner solar system object, and based on our observations this appears to fit the risks. So basically to get the quasi-donut shaped impact crater you need a spheroid object hit land or shallow water, and its going to throw out ejecta many times is size, sort of a scooping effect cause by the inertia of material in the roid compressing and moving outward. The central ring is cause by kinetic melting at the impact and isotatic rebound. So first we have to deal with tactical issues. You cannot make a crater from a mid air collision, certainly would not have isostatic rebound from the central melting. So chixulub is rougly sherical, is averaged surface area to mass is low, reducing kinetic friction. Presumably the asteroids explode because the heat penetration into the surface causes the rapid expansion of volatile chemicals. But if the impactor is fairly dense with few fissures it would not explode, much, it might on the surface, but there's alot of activity on the surface anyway. So the core of the bolloid survives and smacks the Yucatan, causing any vacationing dinosaurs to suddenly wish they had drank more tequila. This star killer is what an occupied ship with high axial ratio, is surface area to mass is relatively low. Now lets say it was a miss, it was headed to mars from say planet x but someone was asleep at the wheel. Ok so its traveling at say 30km/second. shields are not up because the driver is sleeping (prolly had to much tequila). And so lets just say he had shields are up so lets estimate the kinetic load in those shields. So lets just say we have traveled through 1/10th of the atmosphere at 1000 kg per square meter of air, it has to move out of the way at 10,000s of meters per second. E = 1/2 mv2 and we get billion to trillion joules of energy (lots of heat per meter). Not really dissipating the energy because, alas the ship has traveled from (Space) 80km to 20km in 1 second. So now we have power per surface area, which is now nastily in the gigwatts per squar meter range heading at before impact to the terrawatts per meter. So lets just say there is not a shield that can survive this. OK so no windows and metal has melted and cavitated, and the interior plastics are no hot gases and the whole thing has immense internal pressure. Boom. and micro impact craters and alot of dead trees and scattered metalic debris. Ok so our ship comes in nose first, we stave off the explosion for a third of a second or so, but the same thing happens; ships density within a foot of the surface is two low to resist the implosions events followed by over heating and explosion. Your star killer would make a nice mid-air kaboom and break lots of windows and leave a modest crater, but the mass and density is nothing near chixulub so . . . .

See thread on Dark gravity. Nothing new here.

Given that a photon drive is 100 MW/N and we 100MW/120N therefore its 120 time more power efficient that a photon drive. Not good but useful. JUst remember, to get to mars you need to carry a Kilotonn. Solar panels at best would produce maybe 1MW, though we are talking realistically space station size panels at double the efficiency at 300 kw range. That basically puts you in the .4N range sub microg range. Very difficult to get out of LEO with that. Its basically a high ISP ion drive. Very small devices maybe, tugging between mars L1 and Earth L2 maybe, Also remember, that the device has not be tested in space.

Banned for thinking Santa lives in Toronto. Banned for thinking Santa lives Banned for thinking Santa Banned for thinking Banned for Just Banned.

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http://phys.org/news/2016-11-grapes-earth-magnetic-shield.html

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But it is the big future plan, Note I did not bring the topic here nor did I introduce it as a SPACEX topic, SPACEX has pushed this idea and others dropped it in this thread. You can't control peoples thoughts. ANd I would add this point, Musk's and his associates (I assume) Mars dreams are a major motivating factor for a company called SPACEX, so to say discuss SPACEX without discussing Musk's plans for Mars is the same as saying don't discuss SPACEX's future plans, IMHO. Why practice landing space ships under a dozen different scenarios. Chute landings would cut the mustard on Earth, cept on Mars, nothing heavy can be landed on Mars without landing thrusters. These little wait for the last minute and take out 1000 m/s of velocity, thats what you need for landing on Mars.

As I previously said, you can place a hard frozen man on Mars (well if we except the ESA, they would collide him, lol) for the cost of a satellite that can reach interplanetary space. Each of the Mars problems can be dealt with, the question is can they be dealt with by SPACEX. 1. You need a surface targeting system which is precise on the scale of meters (we do not yet have this capacity), You need to establish a bootstrap powerstation on mars, and hope like crazy that subsequent landings do not damage it. 2. You need automated and robotized excavation/drilling equipment that can remove or move martian substate. We have to argue that the current SPACEX business plan lacks the scope to do this, this would require another enterprise of NASA assistence. a. To build a solar or nuclear power station on the surface for required power. b. To begin the process of wiring the complex for power distribution. c. A series of robots to do the above but also repair and recharge themselves. Essentially First step is to build a village of robots. 3. You need to be able to robotically built a close atmosphere environment, preferably underground (Why: your first occupation is to build a greenhouse and protect your plants). Again the vapor pressure on Mars is insufficient to support any earthen life, even deep in Mars surface. You would have to drill several killometers into the surface to arrive at a pressure were plants can grow. However if you drill sufficiently deep underground it is possible to close off caverns and seal them. 4. Robotic micro electricians, to set up an array of leds in the blue and red-orange wavelengths. Also you need substrate (bootsrap) since there is no composted or compostable material on mars. You need to plants seeds and nuorish the plants. 5. While it is possible to periodically transfer gases, some sort of vapor tight plumbing needs to be established between greenhouse and building. If subterranean building are built adjacent to the greenhouses the radiation problem can be eliminated and stable connections can be made between green house and living quarters. 6. So as I am talking you will note that as the colony expands, its surface impact declines, and more of the colony is subsurface. Not the kind of colony where you have Suits romping around on the surface. 7. We have to assume that Martian gravity will suffice for at least a year or two, otherwise you are going to have to provise crew rotations. Yes, as I mention its possible to build a small (3.5 meter in diameter) human centrifuge that humans can exercise in to maintain cardiovascular health, but this is not going to be an early stage employment. So now what about Mars support. That is more than just transport, this means you have a relay environment were stuff is being placed in LEO, then shuttled to MEO (eventually using ION drive ships I an presupposing). And you have an emmense number of these, probably 30 or so) that can shuttle equipment and supplies. The second problem is assembly on ground is almost absolutely required. The reason is that martian parachuting systems are horribly inefficient, and thus payload drops will be small. Thus the payload has either to be a micro version, or just about everything will need to be assembled on the surface. I see surface building on mars being dropped empty and then the interiors being assembled by other drops. I dont see little martian habitats being dropped complete with human inside. The larger the object i think the more difficult it will be to target were it lands, and the more difficult it will be to move if it is mistargeted. What SPACEX says (1 million people) I think is incredible, its 100 - 1000 times more difficult to manage resources on Mars relative to earth. When talk about about a million people on Mars you are talking about the management problem for a billion people on Earth. So realistically we need to talk about practicality, a research colony of maybe 10 to 50 people over 200 years or so, just to get that management problem down by a magnitude. So keeping this on a future SPACEX topic. I think a functional plan is on the scope of about 10 independent SPACEX Mars plans (each unit being a different business model) to provide a bootstrap facility. Beyond that bootstrap facility I think we are clueless as to how to reach the 'cheaper if a million people travel' idea.

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Just to point out that if you bury your on-site storage tanks underground and use trickle heaters around the tank you can keep them at a temperature for an appreciable amount of time. Its the tanks that you need to go in space that will need to be high pressure, but you can store those empty or partially full, removing at least some of the stress. The only way humans fly to mars every year is when we have a massive improvement in propulsion systems (i mean 10x higher ISP and vastly greater energy production per fuel mass). And yet mostly what musk is doing is conservative technologies creating slightly more efficient applications. SSMEs afterall were 460 ISP (tradeoff liquid H2 . . . ) His ISP max are int the 350 range. Nuclear is not that much better, the best ION drives have 10 fold better power but 1000 fold worse power production rate on the generators (Solar panels). The technology is not ripe. I think if you had a mission, pretend this plastic doll is human, see if you can get it to mars and back, that would be mission number 1. My guess that doll would be back in LEO 5 years after leaving LEO. The next ship leaves 18 months later after the first. With good planning and alot of luck, proper staging of fuels its more or less a 3 year turn around. So this learning process is something you do after you know how to colonize an atmosphereless rock.

But unlike space the moon offers a huge inertial sink. It also offers a potentially cavernous interior. So it is possible to put an artificial gravity machine so that astronauts could spend a certain mount of time each day in an earth like gravity. In addition the moons potentially cavernous interior offers a place to shield oneself from cosmic radiation. Three of the biggest problems are therefore removable on the moon with a little effort. I still think asteroids are a better choice, but the moon is not a dead end for colonization practice. Its is because of the challenges of exoplanetary colonization that we need the moon to learn the craft, thats kind of the entire point, because whatever long term problems you have on the moon, they will be a magnitude more difficult to 'manage' on mars. No-one in their right mind expects this to be easy, if it was why go their first.

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High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter A repurposed martian satellite with new adopted missions: Find and explain the surface remains of European and Russian spacecraft. Mission completed. Beagle 2 - critical solar panel failed to deploy - to examine the effects of incomplete deployment on the final state of a spacecraft landed on mars - mission success. We now know that incompletely deploying a solar panel can now explain critical non-communication. Mission completed. ExoMars 2016. - repurposed mission - to examine the effects of smashing a spacecraft into Mars at 150 m/s to determine if the hyperglolic tank will explode. - mission success - we now know that a hyperglolic explosion on contact can create 50cm impact crater virtually disintregating the spacecraft. Not a failure (at least according to ESA) as we now know that smashing at 150 m/sec is so inferior a method compared to having a smashing with a hot fuel tank on board. Notice how there is actually no way to fail a mission to Mars, its simply an unplanned mission repurposing engaging international causality cooperation for unmanned spacecraft observation.

There's always a way to do it wrong though. Top two organizations with Mars curse, what is their relationship with exomars 2016? http://www.bbc.com/news/science-environment-37715202 Ah yes, so we have yet another communication satellite for the fatigued NASA rovers to use? Does anyone remember the Beagle. Technically speaking with a relatively low grade ion drive and the ability to make Mars L1, which isnt that difficult even with an ion drive. Reaching mars orbit is hardly a novel technical feat anymore.

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