cantab

CoaDE shut down some of this. Stealth is a huge aspect in submarine warfare but impractical in space warfare (absent handwavium shields). Active sensing isn't really required either. But some things do transfer, like the relevance of missiles and the ability for their target to try and evade, and the crew quarters are likely to be pretty similar too.

I can settle the question once and for all by means of making the Earth's shape expanding cloud of rubble.

I vaguely remember an Australian who was working on building a cruise missile out of off-the-shelf components, as a "hey this is what a terrorist could do" kind of exercise, and indeed the authorities in Australia pretty much shut him down. So yeah, as always be aware of your local laws. My understanding is that even quite large model rockets can fly fine with just passive aerodynamic stability. Adding a control system is adding something else to go wrong - consider what would happen if it malfunctions and makes the rocket spin out of control, nosedive the ground, or fly sideways far further than intended.

Politics, is the short answer. Discussion of which is prohibited on these forums. So this thread may as well be locked.

So only the innermost 100 km radius. The density (pre-heating) is about 13000 kg/m3 and it's basically solid iron with a specific heat capacity of about 0.4 kJ/kgK . Heating it to a million Kelvin pops out at around 1028 Joules of energy. That's a lot - it's equivalent to several thousand years of solar energy received - but nowhere near enough to blow the Earth apart. So what will happen to it? Well we can discount heat conducting outwards, that process is very slow even with a million K on one side. And though the temperatures are hot, I don't think they're hot enough for significant iron fusion to occur. So the most prominent effect is probably the shock/pressure wave expanding outwards. If we treat it as an earthquake, then the upper limit is about magnitude 13, which is a million times more powerful than any normal earthquake in history. But then it's also a thousand times deeper than most earthquakes. I'm inclined to think the effects would balance out, and the surface shaking would be strong but not vastly stronger than what normal quakes can cause. However, it would be strong shaking everywhere. The effects on human civilization could be devastating, but the effects on natural ecosystems would probably be not so much.

Don't underestimate a fast Core i3, I say. My i3-6100 does great in Kerbal and has handled most things I can throw at it. That said, when paired with a mid to high-end graphics card you will see the benefit of an i5 and even an i7 in many games. There's also benefit to an overclocked CPU, and to running fast RAM. It's all about an appropriate build for your needs and budget. There's nothing wrong with going Core i3, cheap motherboard, budget gaming card, if that's what you're able and willing to spend. There are very few games that outright will not run playably on such a rig. PS: KSP in particular still cannot make good use of more than two cores anyway. With a single high-part-count vessel performance remains limited by the speed per core, so an overclocked 6600K/6700K would be best but the i3-6100 not too far behind.

To be fair, while the Iowa-class have obvious shortcomings compared to modern warships, sometimes you do just want a Really Big Gun.

A mod called NavHUD. Normally it shows a grid too, but you can configure it how you like.

Going by that article, it looks like the Bohm interpretation still shares the key shortcoming of the Copenhagen interpretation: What exactly is meant by a 'measurement' or 'observation'? Without really pinning that down, I don't think quantum mechanics can really be complete or sensible.

It's not an invented problem, radioactive waste is challenging to handle and hazardous if dealt with improperly. But there's an excessive amount of paranoia about it. I think if it were considered more rationally, diluting the high level waste and spreading it in the ocean would be a reasonable way to go, done properly the effect would be insignificant compared to natural background radiation. As for "geological repositories" it seems like often the perfect is allowed to become the enemy of the good, countries being paralysed by fear of unlikely remote events, when the danger of having the stuff lying around at nuclear plants in a concentrated form vulnerable to malicious or accidental release is much greater.

Use the hang glider... I enjoyed Pilotwings Resort. It's an "arcadey" flight model, but what do you expect given its art style?

While the movie scene is surely an exaggeration, prop planes can do some pretty cool tight manoeuvres, notably the Lomcovak family of manoeuvres that rely on the gyroscopic effects of the engine and propeller. https://www.youtube.com/watch?v=skfprThzUq4

Something related does actually work to an extent. Major users of electricity that can accept power outages can agree with the electricity grids to be first to be disconnected, to help the grid match generation and consumption. This goes some way towards dealing with the "when the wind doesn't blow" problem. The other answer to inconsistent renewables is larger grid scale, though that has its own challenges.

2012 was hilarious. Pure comedy gold. I literally burst out laughing in the theatre when they were flying away from LA.

I think in at least some cases the same technology *is* used for artificial gravity and for propulsion, or at least nothing ever says it's not. In even more cases the technology for artificial gravity and for 'inertial dampeners' (to excuse ships pulling crazy gees) is related. Centrifugal gravity imposes significant constraints on ship design that magic artgrav doesn't. Out of universe, of course it's for filming practicality. Zero gravity is hard to film, even centrifugal gravity is hard to film unless the ship is meant to be really huge. That said, it would be neat to see accelerational gravity, and spaceships shaped not like ocean liners but like skyscrapers, their engines at the bottom. If your ship is running its engines constantly anyway (which is possible given enough delta-V) it would make sense, and at the very least it could be a striking visual style. As for sound in space, well I just accept that the microphones I'm hearing aren't in the same place as the camera I'm seeing. There will almost surely be noise on the spaceships themselves.

Well that's how nuclear power is operated. Partly because some (though not all) nuclear plants are slow to change their output, but mainly for economic reasons - the cost of running a nuke plant does not depend on output. The same economic situation applies to wind and most solar, but I think they can technically change their output quickly provided there's wind or sun available. On the other hand for power plants using fuel (whether it's fossil fuel or renewable biofuel), it's best to burn the fuel only when the power can be sold for good money, which means meeting peak loads. Some hydro and solar systems that can effectively store water or heat share that behaviour, and hydro can change output very quickly too. Realistically we're going to have a mix of generation. Most solar has the blatant disadvantage of only working in the day.

"The authors calculated that when wind energy is used at its maximum potential in a given region, each turbine in the presence of many other turbines generates on average only about 20% of the electricity compared to what an isolated turbine would generate." In other words, trying to extract all the wind energy affects the wind and gives diminishing returns. No poop Sherlock.

Yeah, it entirely depends on speed. As far as what actually happens in Star Wars and the "Extended Universe" goes, there are of course a few examples. Most obviously, we see the large spacecraft in The Force Awakens, and it turns out that's an Executor-class. Its low-speed crash landing, slow enough for the ship to survive largely intact, did not significantly affect the planet. At the other extreme, a planet that was hit by a large starship in hyperspace was "fractured to the core", likely rendering it uninhabitable. But how fast might a Star Wars ship ram a planet in "normal space"? It's hard to know, because they don't appear to follow normal orbital mechanics and their speeds are quoted in fictitious units of "Megalights (MGLT)" or "MGLT per hour". It's shown, in a background shot, that the Death Star was about 3 Megalights from Alderaan when it fired. And the novel mentions it's about "six planetary diameters" away, and Alderaan is about the size of Earth. That suggests that 1 MGLT is 25,000 km. Then we know that the Imperial (I) Star Destroyer could do 60 MGLT. Yeah, Star Wars using the same unit name for speed and distance, whee. But it's probably 60 MGLT per hour, so 1.5 million km/h or 400-ish km/s. That's fast, even by full scale solar system standards. The fastest anything on a solar orbit can hit Earth is 72 km/s. What about mass and density? Well, no idea, maybe I'll look into it later. But with that speed meaning that kilo-for-kilo a Star Wars ship at full speed would be about a hundred times as destructive as a natural Earth impactor, and with the general scale of Star Destroyers, I feel confident that full-speed ramming would be immediately devastating and likely render much if not all life on the planet extinct. Though in practice in the Star Wars Universe, decent planetary shields would stop it. It's a waste of a good Star Destroyer though, considering that a single ISD could use its guns to turn the entire planetary surface to glass and kill everything on it in about a day. (Again provided it's not opposed by shields or surface weaponry).

A few things to think about: Actual number budget, of course. What's your main goal? Different equipment works best for visual observing, deep-sky imaging, and planetary imaging. And video astronomy (the 'special term' you said) is very much in its infancy. Most amateur astronomers start out with visual observing, but if you're coming from a photography background you might like to jump straight into imaging. Where will you be observing from and what are your physical requirements? If you live in a house in the countryside then a bulky setup requiring mains power might be fine. If you live in a city apartment you'll want something you can carry up to the roof, or down to the car (or even bike) to drive out of town for dark skies.

It's great to get the plasma controlled, but really just a stepping stone. The goal is net power and that still seems some way off. I'm also sceptical that fusion power will meet the hype. It still has radiation problems, using tritium fuel and emitting neutrons that turn the reactor casing radioactive itself, which means decommissioning the first fusion plants will be just as problematic as decommissioning fission plants. (And aneutronic fusion is even further off). It's still going to be costly to research, develop, build, and maintain fusion plants. I don't know how rapidly fusion plants will be able to change their output, and you need some rapid-response power generation. Perhaps I'm just "Once bitten, twice shy", because nuclear fission power had all the same hype in the early days and over time its flaws have become very apparent.

I recently switched to this picture, because it's just stunning https://commons.wikimedia.org/wiki/File:Peacekeeper-missile-testing.jpg

To my knowledge there's no known relation between solar activity and earthquakes. I think there have been hints of a relation between the moon's position and earthquakes, which has an obvious physical cause, but even then it's weak. There's no reason to think recent events are anything more than coincidental. Now if we had half a dozen major earthquakes in different places in a week, then I'd suspect something interesting.

Acceleration due to gravity is given by g = m / r2 So if g is the same but r is reduced (Kerbin is smaller than Earth and has the same surface gravity), m is reduced by a greater factor than r. And orbital speed is given by v = sqrt (m/r) And that m/r term will be reduced for Kerbin compared to Earth, which means a lower orbital speed. (Ignoring constants in the equations. And the small correction because we don't orbit at zero metres altitude.)

You've done it, the new forums call it "Likes" not "Rep".

Composite armour, an RTG, and a couple of turreted lasers with cap/battery banks for burst fire. I may have been playing too much Children of a Dead Earth.