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You would need to keep the crystal in a vacuum ,and somehow suspend it. Even magnetic suspension will transmit vibrations (the magnet will vibrate). Crystals have extremely low losses, but still far too much to be practical for energy storage

Really? you think they could hide rockets exploding when the whole world was monitoring it? The most expensive part of a rocket is the turbopump. By comparison, designing the rest of the rocket is almost easy once you have a working pump. If they can just salvage the pumps, they will save at least half the cost.

There an even simpler way. Build a large square matrix, of size r*r. Now count how many points of this matrix are less than r away from the origin, you can do that by checking if x²+y²<=r². The points that fit that rule are within a quarter disk of area pi*r²/4, and the whole matrix has an area r². So take the number of points in the quarter circle, multiply by 4, divide by the number of points in the whole matrix, and you get an approximation of pi. the more points in the matrix, the more accurate the result. You can optimize by: doing that only for one half of the matrix (it's symmetric along the diagonal) measuring the surface of a ring with r1 > distance >r2. If you do it smartly, you will only have to check a few points (all points in the ring have neighbours that are also in the ring) massively parallelisation of the task.

Crystals with very high quality factor will be able to oscillate for a few thousands cycles before spending all their energy, which means a few ms. The main problem is that vibrations propagate out of the crystal. It would be like shouting in a glass and quickly putting a cover on top, the vibrations of the medium cause the rest to vibrate, and you loose your energy very fast. A relatively good way to store energy as vibrations is to use a large pendulum in vacuum. I don't think you can keep one running for much more than a day or two though.

It's a giant dampener and a bunch of thermonuclear weapons. Using explosions to propel stuff is not exactly new technology, and neither are springs. The only difference with what has been built is the scale. Building a dampener able to support the weight of a generation ship, or a delivery system for thousands of bombs is not trivial, but it is just a scaling problem. It's like going from building a small boat to building a large ship: it will take some work, some good engineering, and some new infrastructure, but not scientific breakthrough. At the time of project Orion, they thought they could do it in 10 or 20 years.

Russian space technology works very well, with no fatalities during spaceflight since 1971. It is a bit crude, and probably not the most fuel efficient, but it gets the job done. Given the records, I'd prefer to fly SOyouz than whatever NASA manages to fund next. That being said, having parachutes or any form of emergency solution is always a good idea when humans are flying.

Nuclear pulsed propulsion: using nuclear bombs as a propulsion method. http://en.wikipedia.org/wiki/Project_Orion_%28nuclear_propulsion%29 It has massive ISP and TWR, and uses technology from the 50s and 60s, basically a heavy duty plate, a shock absorber, and bombs. Of course, nobody ever tested the concept since it involves detonating a large amount of nukes in the atmosphere, and it doesn't work for small ships, but it is not especially difficult to build once you have nuclear weapons.

I'd like experiments for my satellites: imaging, radar, spectroscope. They could be big, heavy, power hungry and in different nodes, to motivate players to have either flotillas or put them on large stations. I would also like parts that could do some on site analysis: mass spectrometer, x-ray diffraction, etc. The idea would be that if you have them, you could transmit a bigger ratio of science. Same thing, these parts should be challenging, but less than a return mission, and different nodes, to motivate players to improve their rovers. If we ever get missions, we could get one-shot experiments too. A big, expensive part that needs to be put in a specific place to work (orbit, high orbit, solar orbit, etc) to measure one thing (cosmic radiation, solar flares, gravitational waves, etc)

To avoid the transmission spamming and make players have goal oriented missions, a simple idea is to make parts like the goo canister and the material bay work only once. Right now, I can send a probe of a Mun free return trajectory, and use a single goo canister to get science in 8 or 9 biomes, even without using transmission. If each goo canister can be used only once, I would have to choose between putting 5 times as many or bringing them back, and would send separate missions to study different areas.

The ultimate goal is to land on the launchpad after separation. If you use parachutes, you'll fall down somewhere east, in the ocean.

It's nice to see posts by people who know what they're talking about. That being said, I disagree on the usefulness of dividing phenotypic effects into genetic and environmental. Some phenotypes are clearly commanded by genetics, such as eye colour, while others are clearly caused by environment and behaviour, like deformities caused by teratogens or repeated activities. Of course, there are lots of traits that are a combination, and we're used to the terms genetic predisposition and risk factor.

We have the technology to do it, and we don't need any large-scale space-based manufacturing sector. We could build a giant ship made of steel and concrete and put it in orbit, and the price would not even be that ridiculous. But to put it in orbit, you would need to blast a lot of nukes, which would be terrible for people staying on Earth, and that's a political and social problem. Faced with an extinction-level event and enough time, that would be a sensible solution.

We could make a generation ship now, with nuclear pulsed propulsion. At project Orion, they were thinking of sending whole cities to Mars. Also, if you build machines with the goal of improving themselves, they will always want more energy. It is possible to limit expansion by defining specific rules, but expanding to use all available resources is the default state for self replicating machines.

You would need some pretty insane accuracy in your trajectories to catch anything like that. The best proposition I've heard is the laser broom. Use a laser to ablate part of the debris, which causes a little thrust and a change of orbit. If you did it right, the new orbit will have a lower apoapsis and decay rapidly. If your laser is powerful enough, you don't even need to focus and aim precisely, and you can 'sweep' a number of debris at the same time.

The brain is not symmetrical, and has a dominant hemisphere. It's still a bit of a mystery why certain parts are symmetrical and others not, and what makes an hemisphere dominate the other. It could be genetic, environmental or behavioural factors that decide it. Brocca's area, for example, is on the dominant hemisphere, which means it's not on the same side for right and left handed people. I think we have developed this asymmetry as a smart way to manage brain resources. Throwing stuff used to be critical for survival, and we are insanely good at it. This suggest a significant part of our brain is dedicated to that task. On the other hand (ha ha), if you are already able to throw stuff with great accuracy from your right hand, it's not very important to be able to do it from the left hand too, so the most efficient use of your brain capacity is to invest more on one side. You can then either let the other side underdeveloped and save energy, or use it for other tasks (more likely).

I knew thorium was a common waste of rare earth production, but I wasn't aware rare earth ores were a big part of the thorium reserves. According to wikipedia, thorite is the most common ore of thorium, with 12% content, compared to 2.5% for monazite, but it is mined for its uranium content, so I guess it is prospected for too.

Depends. If it's low power, normal battery. That's what is used for retina and cochlear implants, as well as pacemakers. For retina and cochlea, the battery is usually outised with an inductive power transmission through the skin. For more power, you'd have to go fuel cell. Inside your body, I imagine glucose/oxygen fuel cells would be the way to go, but current prototypes are still very low power. Otherwise, metal/air fuel cells are extremely promising in terms of charge to mass ratio. They are not exactly rechargeable, but the electrolyte can be recycled.

Another issue with typical generation ships, is that you build a self-contained colony, that can sustain a limited number of people. So for a few generations, you need to have strict birth control, and basically build a culture centered around equilibrium and stability, with the goal of ultimate expansion. I don't see the people willing to embark on a centuries long journey to expand the human race being very strong on the growth control thing and the idea of living in a supersiezed tuna can. I don't see their descendants breeding like rabbits once they arrive either. Ending with a generation ship in orbit of another star full of people content with barely replacing their population and not interested in exploration is not desirable. Anyway, any type of slow travel will imply some form of social engineering (brainwashing) to keep the crew focused on the initial goal generations after the launch, and forcing generations to come to cope with your choices. It's an ethical nightmare no matter what solution you propose. Requiring the crew to breed is probably one of least unethical things in this context.

There's also the fact that we currently have no industrial use for Thorium, so we basically throw it away and never look for more of it. The day it becomes a strategic resource, you can expect prospecting to be funded in pretty much every country and the known reserves to explode.

There is also the possibility of social healthcare paying for augments. From the tone of the discussion, I assume that most of you are from countries with pretty much no public healthcare system. I'm from France, where the government will pay for reconstructive surgery (ie boob job after a mastectomy), dentures or glasses but not for esthetic surgery or laser eye surgery because they are considered comfort things rather than useful ones. If we had super bionic eyes or livers available tomorrow, and they caused a big difference in job opportunities and life expectancy, I think we would subsidize them. If they just made you better at sports, we wouldn't pay for them, and I don't really have an issue with rich people having better stuff. I know in countries like the USA, socialism is almost a swear word, but many people like it. If a new technology that could help mankind ends up increasing inequalities and human exploitation, the fault is probably not in the technology.

Still about the gyro. You can use it to show the sun doesn't move significantly during the day, but that the Earth spins. That already one part of geocentrism broken. Foucault's pendulum does the same, but is a bit more difficult to explain to the layman. The angle between the sun and the direction the gyro points at should change by about 1° per day, which should be measurable with a decent gyro.

The concept of generation ship, as it is generally shown, doesn't appear very realistic to me. If I was in charge, I would put a small crew, let's say a few dozens, of women, and a few tons of frozen sperm and eggs. That way, you can sustain a large genetic diversity while moving a minimal weight. I would restrict the crew to females because you will need to breed several generations, and you don't want to waste life support on males. It also allows each woman to bear less children, and limits the consequences of infertility risk. If you have artificial wombs, or metahumans, the sexual segregation is not useful anymore. With a small crew, rather than a heavy cylinder, you can have a smaller habitat at the end of a tether spinning around the main ship. How much machinery you'll need once you're there depends on your technological level. You would need a few furnaces to process metals and other raw elements, some reactor tanks and general chemistry equipment, and finally a microchip foundry. If you combine that with a vaccuum-chamber 3D printer that can print several types of materials, you have pretty much everything you need to kick start a colony once you're there. I think you could fit all that into a modern ship. Of course, it relies on you building tools once you arrive. If you want to carry all the tools of modern industry with you, you're looking at a town or city in term of scale. Think Hong-Kong, but with every thing in storage, all housing and service infrastructure removed, and 200 technicians to keep it in a good state.

What about a high precision gyro? Assuming you're on the equator, if it is set up to be perfectly vertical at noon the first day, after 3 months it will be horizontal at the same hour, and you can show the direction 'turns' at one rotation per year, consistent with the heliocentric model. Especially since it won't move relative to distant stars.

If the rock is outside the physics radius, so is the kerbal on top of it.

how is that different from throwing money at crazy ideas from non-credible people? Well, at least you're not trying to con anyone but your money would be better spent on a nuclear physics book.