Nuke

better idea, abolish any coin smaller than a dime.

i think you are confusing ceil() with floor(). round(x) is just floor(x+0.5). using ceil() means if something costs $3.99, my mind just sees a 4.

i came up with another idea, what about those little engine on a chip devices? you know where you have a small mems turbine generator running on some kind of hydrocarbon fuel. obviously using a carbon based fuel would have its issues, but what about h2o2. your exhaust is water vapor, and oxygen. such a device would be packaged with a fuel reservoir that would last several years. of course such devices need to handle the water vapor in the exhaust so it stays out of the electronics, but i think its something that might be plausible for low power devices.

i always wondered if these kinda things existed. this things molten rock moon is interesting too, i assume that heat comes from tidal stresses.

once again i am impressed by canadian nuclearness.

in an emergency yes they can shut down pretty quick (scram). i dont think its good for the reactor though, you dont want a lot of rapid thermal changes. for general maintenance and operation i think the preference is to shut it down slowly over the course of several days. in a grid setting i think nuclear is the last thing you throttle back.

back in the olden days people who wrote malware actually wrote their own code. these days their code consists of one file with a bunch of #include <somelibrary.h> at the top and hit compile. these are the same libraries used in legit applications. as a result safe programs look like viruses and viruses look like pictures of cats.

this is what you call psychological pricing. by taking a penny off, people think they are paying a buck less, because most people dont pay attention to anything to the right of the decimal point. when i go shopping my brain automatically calls ceil(x) on all the numbers before adding them up. it gives me less headaches and i dont have to worry about not being able to cover the sales tax. buying stuff is too hard these days.

seems there are companies out there trying to bring back betavoltaics. http://www.widetronix.com/products they actually have some numbers about what kind of power you can get from their devices. they got a tritium based device you can source a microwatt for 12 years, and a nickel63 device that can source 500 nanowatts for 100 years. you can run a microcontroller with that if it spends most of its time in sleep mode, waking up for a few seconds and then going back to sleep. you might be able to accomplish burst transmissions (a few bytes over a very short period of time), but this wont work for voice communications (maybe text messages, tough you will need to wait for your caps to recharge after each send).

im wondering about some kind of motor/suspension hybrid where the wheel is essentially on a magnetic bearing that also doubles as the motor. the wheel rim is essentially a ring of neodymium magnets floating about the hub coils so it would allow some wiggle room for shock absorption. this might be used in addition to some kind of active suspension. it would take some rather complicated control stuffs to make it all work without being totally unstable.

ssds make everything faster. i dont expect to see mechanical hard drives on the market for much longer. especially with moore's law making ssds halve in price every 2 years.

yea some of the things used in leds are rather nasty, things like arsenic and germanium. one common hack is to use leds as light detectors by reverse biasing them, they will allow current to pass when exposed to whatever wavelength they produce when powered normally. detection is completely different from energy production though.

i never said any of that is practical. venus is such an impractical place for a manned mission. i think a manned mission to saturn (not its moons) would be more successful and would make more sense. that second part now, about blowing up its atmosphere (especially after seeing tonight's episode of cosmos) i see that as a distinct possibility. the obvious method is brute force, smash a freaking comet into it. a better option would be to take that gas and move it to mars, terraform 2 planets for the price of one. perhaps a glancing blow with precise timing can send some of that gas out on a mars crossing trajectory. im sure there is a less crude way to pull it off though.

there are betavoltaics which use tritium to produce a very small amount of power. i dont think they are powerful enough to run a phone though. they were used in pacemakers prior to the invention of lithium ion batteries. i could not find any actual numbers from actual devices, but from what i was able to find is that they usually produce power on the order of tens of microwatts to milliwatts. i think the main problem is that these kinds of devices depend on isotopes that do not exist in nature, and have to be produced as side products in nuclear reactors. so they are expensive, in limited supply and just not economical. tritium goes for $30000/gram.

roll control doesn't sound that hard to do. tilting an engine on x or y gives you yaw an roll control, you can generate a quat to store those rotations and multiply them together, and this gets applied to both the gimbal model and the thrust vector. make a 3rd quat to store a rotation for the roll axis, except this axis is going to be between the center of gravity and the gimbal model origin, but flattened on the local z axis. this can just be multiplied into the final rotation. this is then applied to your final thrust vector. simple maths. im supprised squad didnt bother trying to figure that out when it did its gimbal code.

some wavelengths of light can penetrate cloud cover better than others. couldn't you optimize your panels to operate in those spectra? this may require materials other than silicon though, sort of like how different color leds use different semiconductors to produce different wavelengths of light.

i figured it out from the op, and subsequently posted about it (look up).

i think your biggest problem would be your ascent stage. this video seemed to indicate a vtvl ssto. this ship needs to operate over a wide range of temperatures and be capable of pushing through the atmosphere of venus. you also need a rocket engine that can handle a wider range of pressures than what is used for earth launch. some kind of nuclear thermal rocket that can operate in both open and closed cycle modes (on hydrogen or atmosphere) would probibly work, provided it can be run in the hot atmosphere of venus without melting down. it might also be possible to use an "air" augmented rocket, the dense venusian atmosphere may actually work in your favor here. the good news is that you can probibly land a mostly full rocket, the atmosphere is dense enough that a small de-orbit burn, and a small amount of thrust near the ground for final touchdown would be all that would be neccisary. the thing is you are going to need to bring a lot of heavy refrigeration hardware for survival on venus (ice a thousand degrees below zero cannot exist, coldest you can make something is 0k, which is -459.67f, or -273.15c, fortunately refrigeration is a well known technology). short duration suits can probibly be built. they would be well insulated and carry much cryogenic coolant, vaporization of which would cool the suit. of course you run out, you have a very short time to get back to the ship. it would be of design similar to the newt suit, but it would need to be made with high temperature materials, and given the gravity of venus and the bulk and weight of the suit, it may need to be robotically augmented to allow ease of use.

using liquid metal coolant is different from a molten salt reactor. msrs usually have the nuclear fuel dissolved in the salt, so the salt is the fuel. the russian topaz reactor was still a solid core reactor, i believe it was cooled with NaK alloy, but this is only a heat transfer medium. the aircraft reactor experiment back in 1954 had one of the first molten salt reactors ever built, the reactor was ran for 9 days. this was followed by the molten salt reactor experiment in 1965. the resulting 7.4MW reactor ran for a year and a half at full power. i think msrs were pretty much shelved in favor of research into fast breeders back in the 70s. blame nixon, its all his fault.

even if the majority of people are in favor of owning electric vehicles there are still going to be those people in harsh climates that will still need to use gasoline because of limits in battery technology. i kinda spent a few years in phoenix and know what kind of mayhem hundred degree weather can play on a regular car battery. im kinda curious about using active temperature control of the battery compartment. if a well insulated battery can maintain its temperature within its safe operating range using the regular air conditioning hardware you usually find under the hood of most vehicles, it could solve the problem, of course at the cost of range and weight. in a hot sunny climate it may be possible to maintain the temperature of the batteries with that backup solar panel i mentioned earlier. so you can maintain charge, maintain battery health, and keep them from blowing up.

all i can say is go canada. please invade us.

seems desert environments you could just have a fold out solar recharge panel for emergencies. you could even have them integrated right into the vehicle's roof, not only is it good for emergency recharging, but also to maintain charge to keep the battery in prime condition (free trickle charging, eliminate the issues with charge loss). for infrequently used vehicles it may be possible to keep the batteries charged in certain climates without plugging it in at all. i also rather like having a removable gas apu that you can install in your electric vehicle as a range extension if range is required, or otherwise left in your garage. you might even see these kind of things as standard equipment for electric vehicles in the not too distant future. i think the range issues are sufficiently solvable such that its not even worth bringing them up. the real concern is beefing up the power grid to support electric vehicle infrastructure. use gasoline in power plants where efficiency and pollution can be controlled, replace coal with nuclear plants designed in this century (*points at canada and claps*), use renewables wherever viable and use storage tech to maximize their effectiveness, get fusion working at all costs. if there is a thing you can do to make the grid more efficient, do it.

in a fusion reactor you dont need water that is as readily available in a nuclear reactor, since the reactor can be shut down quickly if there is a shortage. so its probibly acceptable to source cold intake water from the normal utility. the hot end of the heat exchanger (where the heat exchanger is the sink side of a brayton cycle) goes out for public consumption as hot water/heat. by the time the water goes through the consumers, the water treatment plant, and back to the reactor, it is cold again. the hot water would mostly go to industrial centers built around the power plants for basic applications like heating and manufacturing.

i actually rather like the rail-rocket approach, the missile is a fully guided warhead with enough delta-v to make minor course corrections en route to target. it is however launched from a big honking rail gun (or perhaps gauss, not sure which is better on power usage and dealing with waste heat) so that it may reduce the close in time (and thus the reduce deltav needed to stay on target), and increase the ke of the projectile. just because the idea is ripped from star trek, doesn't mean its not a good idea.

this is what i like to call the iter yardstick. you take a well understood design, the tokamak, which is also one of the most complicated and expensive reactors to construct. then you create a plan for a prototype reactor that will take a 50 year 2-stage multi billion dollar research program which does not result in a commercial design, and even if it does it will be so expensive that no one could afford to build one. then you use this as the yardstick by which to measure every other reactor concept. this just perpetuates that silly notion that fusion is always 50 years away. fusion is however many years away it is. even though i think the results will actually work, i dont think its the best use of research funds because the end result is less economically desirable than fission plants that we already know how to build. id rather fund all the small fusion concepts that show promise (dont fund quack science) and economic feasibility, than stick all my eggs into one very expensive basket.