Nuke

this thread reminds me of this: https://what-if.xkcd.com/4/

if you have enough foam to make a planet, it wont maintain its foaminess for long. it will collapse into a liquid or solid (depending on the composition of the foam, you can make foam out of everything from soapy water to aluminum) near the core. you might have a sea of foam near the surface though.

you could probibly reinforce a soda bottle with epoxy and fiberglass/carbon fiber. the bottles are thickest towards the base and also around the opening, but paper thin around the cylindrical part. wrap from under the ridge beneath the cap to the tail end should be sufficient to contain pressure. i think the typical way you lay out fiber composites is to lay down a layer of epoxy and then lay down a fiber mat (for a bottle you might want to wrap the bottle, overlapping once, and alternate your seams). repeat while rotating each additional layer 30 degrees from the previous one. give it a final macro coat of epoxy. you then vacuum seal the finished part in a plastic bag and you can use heating pads to accelerate the curing time.

what if an antimatter star collapses into an anti black hole, then you collide a regular black hole with it?

like those diode pumped solid state lasers, i figure you could switch such a laser fast enough to be useful in communication. i think another part of it is picking a laser with a wavelength in one of the host star's dark bands to make pickup and filtering a lot easier.

as soon as one blows up they are going to be declared unsafe. nasa will use them for a few more years, and then can the whole line. a few years after that the government is going to want a new ship. they are going to spend billions to re-develop 1960s technology. the project will get canned right as the last screw is being turned, and a cheaper even more sloppy project will take its place. meanwhile in russia, they will be launching a mars ship.

id go with a small lipo battery over a cap bank due to size constraints (if you want lots of capacitance, you are going to need a large bank). some of them brushless motors eat power like it was nothing.

you need solenoid valves to regulate oxidizer flow to each of your engines. cycling the valve open and closed will regulate the oxidizer flow to your combustion chamber which turns the engine on and off (you need an ignition source too). you do this at a fixed frequency but you vary the duty cycle (this is called pulse width modulation). the duty cycle is the ratio between on time and off time, this is what you change to control your throttle. but remember you are controlling a valve, and this will limit your frequency to the maximum cycle time for the valve, i figure tens to hundreds of hz. ignition is a problem. you could use like a glow plug or something like that, but you need an initial ignition source. you could also use a boost regulator to make a spark gap, running continuously during operation (good luck keeping your electrodes from vaporizing). i think the hardest part would be machining the nozzel. of course thats because i dont have much shop experience. an ardupilot board should work for the control side, though you are going to need to tweak the firmware to handle your engine control. they normally work with hobby servos and escs, but you are going to need different timing than your typical hobby servo to make it work. you are also going to need driver transistors because your mcu wont be able to push enough current for the valves, and you are going to need flyback diodes across your solenoid terminals, because inductive loads play havoc on semiconductor devices. if you ask me it sounds like a lot of work and money for a high school egg drop.

just compile planet factory to 64 bit when the time comes. i will be happy with that. if they can solve the problem with kerbol needing to be the center of the universe that would be great.

engines aren't your problem. control logic, thats your problem. you need to control your descent and then at the last moment, kill your momentum and soft land your egg, then take off and go land/crash somewhere. you can always use pulsed operation hybrid rockets. changing your duty cycle gives you control (pitch and roll, id just damp out any yaw with big fins). then you need to run an inertial measurement unit and some kalman filtering to give you a good enough reference to keep your ship level. you can use an ir or ultrasonic range finder to give you a good landing solution. an arduino would probibly give you sufficient computational power.

thats easy. pull of your f9 key, and throw it out the window.

what reactions yield antimatter particles?

love what you did with the title. not too fond of logitech. ive had ch fighterstick, pro throttle, and pro pedals since 2006. they still work great.

i think they might have a couple of issues with deploying and retracting. then there is the problem of damage from space debris. especially the former in the event of the latter. frankly we dont have very much experience with sails at this point. not to say they wont work but it will certainly be a learning experience.

it is actually very hard to gauge distance of distant objects. human vision evolved to detect the distance of objects that are nearby. but the accuracy of this detection falls of greatly with distance. also the closer to the ground the faster it would appear to move. a small quiet cessna may appear faster than a fighter jet at several times the altitude and speed. if i were to poke a guess, i say what you saw was a private jet. they are very fast and fairly quiet. even close to the ground.

the range of the radio has more to do with transmit power and receiver sensitivity than frequency. consumer grade parts are not going to have the range of some of the space/military grade equivalent hardware. those consumer grade parts are also limited by fcc regs and aren't very powerful.

my definition of a stage is whenever the configuration of the vehicle changes significantly. stage one you turn on the engines, stage two you drop some boosters, stage 3 you drop some tankage. all very significant changes to the configuration.

you need about 13 jupiter masses to sustain deuterium fusion and 65 jupiter masses to sustain lithium fusion. this would still just be a brown dwarf. http://en.wikipedia.org/wiki/Brown_dwarf you would need about 78.6 jupiter masses to have an actual star. http://en.wikipedia.org/wiki/Red_dwarf

any aircraft sent to titan or anywhere else with an atmosphere would be a milestone in robotic missions. you need to learn to fly before you can learn to fly awesome.

the aricle wants to send a big mothership and a small quad copter. i say instead just send a large drone and omit the mothership enirely.

i wouldn't even have a mothership. id just build one large quad copter with the rtg and everything else you need. the mix of low gravity and and high pressure means that you really dont need much power to stay airborn. not to mention the atmosphere is cold enough to use superconductors in the motor coils for even more power savings. also you are going to have a lot of cooling on your rtg so its power output would be higher than usual. i would also do a winged varient to allow for soaring to save power while operating transmitters and other instruments, sort of like this: or here is a better design: this one gives you some serious speed. so you could get coverage that would be impossible with a rover or even a dedicated quad copter.

i bet them cows were scared. i guess they are there for the victory bbq.

hydrogen doesn't fuse so well. thats why stars have to be pretty big to ignite. if six teratons of comet fragment impacts cant initiate fusion on jupiter, tsar bomba would not be able to scratch it.

you probibly just had a case of unseated parts. the "wiggle it" technique usually works here.

i dont think so. in the future programs are going to grow even more complex than they are now, and its very hard to discribe a complex system with diagrams. case in point, hardware description languages. in the olden days when you wanted to design a cpu or other digital device, you did it with schematics of the logic gates, which are themselves very intuitive. but as digital design become more intricate, schematics were no longer sufficiently intuitive. languages such as vhdl and verilog came into existence to define that hardware with code. initially for simulation, then for use in devices such as clpds and fpgas. they are also used to design new architectures. designing a modern cpu would be very difficult with schematics. there are some niches where it works though. robotics is a good one, you got things like ladder logic and robotos. where the control over the system need not be very granular. also for educational purposes, like what the op wants. i remember programming my lego smart bricks was always fun (though these days i use nqc/nxc).