Maybe. But maybe it takes so much energy to bring the other power sources to fruition that you need a massive source of energy to begin with; and, it's only worth the effort to power things like ships that need more compact energy sources.
Taking a cue from science fiction: If I remember right, in Star Trek lore, the Federation gets it's supply of anti-matter from a particle accelerator built on a platform in close orbit of Sol. It extracts the energy necessary to run the process from the star. It's not efficient; so, the only place it's worth using is to power starships. They use more mundane methods to generate power for use on the planet surface.
Hell, it would give us something to start beaming signals at like mad in the hope of a return at the very least.
You should be careful what you ask for. There are things you really shouldn't poke with a stick -- Bears for one, large cats, wasp nests, hives of locusts... Aliens advanced and hungry enough for raw energy (and materials) to build Dyson spheres.
You could certainly build fusion power plants. Lots of them. As your power requirements go up as a society, you just build more. Except... The waste heat. No power generation process is 100% efficient. In fact, 30% may be a reasonable number for a nuclear plant. The remaining 70% becomes waste heat dumped into the environment. Now, what happens to the electrical energy you made -- the 30%? Some of that will get turned into "stuff" or into forms of potential energy. A substantial fraction will likely get converted into heat. So, as you build more and more power plants, you put more and more heat into the environment. You can already see this in localized heating of rivers where power plants draw water for cooling. If society becomes orders of magnitude more energy intensive than we are now, the heating of the environment could become a significant problem; and, the same would apply to any hypothetical advanced alien society.
As to where you get the material to build a Dyson sphere... To begin with that's a misnomer. No one would build a sphere -- they'd build a ring or a large number of orbiting platforms. As you pointed out, the solar system is vast. If your society is becoming advanced enough, large enough and energy intensive enough that you might consider a Dyson sphere, then you're probably going to have (or be able to develop) the ability to mine the non-habitable planets, asteroids, etc. for the raw materials you need.
It's very simple... NASA offers $51 million. Another party offers several million more. U.S. wants Russia to embrace capitalism; so, they do. How can we argue with that? We'll just have to hitch a ride on the next bus. Remember when you were a kid and had to borrow your parents car? You don't like the rules, buy your own.
Yes, yes. I'm aware there are services that will print you off a unique part from a CAD model -- the company I work for has used them. They're using one of the 1/2 dozen commercial machines, cost to purchase running 6 figures. What I meant was I'd like to see a machine available at a low cost.
That's one way to go, but the same could be said of the additive manufacturing machines that use plastics -- why not just make a mold and pour molten resin or a two part mixture like epoxy or polyurethane. Another issue: making a metal part in a mold requires you have a kiln capable of melting the base metal and are willing to pour molten metal in your workshop. Not everyone wants to do that kind of hot work
Truth be told, for my applications, I could simply throw a block of metal on a mill and make the parts I want -- and that's what I currently do. There are complex shapes that can be made with an additive process that can't be readily done with a subtractive process or by molding a single piece. So you end up making multiple parts and assembling the components.
I'm envisioning a device that lays down layers of powder and sinters it with a laser. Yeah, I know it is commercially available but I don't want to spend 6 figures on the machine, just to play around and make small parts. I'd like to see one with cost on the level of a few thousand dollars. I don't care how slow it is... I can wait a day or two for a part. Seems like I've convinced myself to try to build one.
That's a reasonable idea if you can live with how coarse the results might be. minimum line width would be the weld seam width, which depends on the power, feed speed, and the wire diameter; and, control of position would depend on how consistently the arc stays on the line. You would also need a compatible metal base to start with -- You have to weld to something substantial enough to strike an arc on and maintain the arc, without blow-through, until you build up a couple of layers.
Right now all the cheap ones are only capable of making plastic parts. I'd like to see a low cost metal powder additive machine. I don't care if it's aluminum or titanium (cheap or expensive) base metal.
Yeah, that's a great idea. We'll declare war on a species that already has at least a basic mastery of space travel... All they'd have to do is drop a couple of asteroids on us, liquify the Earth's crust and it would be all over.
And that music... Why oh why do TIE Fighters transmit such loud music? Would seem to negate any hope of stealth attack, with the theme music announcing their presence.
Of course they're cutting funding. Green Banks has come close to finding the aliens living in orbit around a couple of nearby stars on several occasions. Damn close. The government needs to cut funding to prevent identification of the aliens --- the powers that be are aware of the aliens and know what kind of retribution they will bring on the Earth if humans become aware of "other" species existence. There has been very limited contact through Air Force satellites. The aliens have made their intentions very clear: As long as we remain a quaint backwater planet with no ability to travel off the small rock we live on, we are not a threat. As soon as we become a threat, the simplest course of action is to exterminate all life on the planet (that would be us). If Green Banks manages to identify the aliens, noone will be able to keep it quiet. It will drive interest in space exploration, funding for the space program, development of space vessels and then the genie is out of the bottle, so to speak. It cannot be allowed to happen. So, it is the Government's intention to quash funding for NRO and NASA, for the preservation of the human race.
Almost there but not quite. First step is to put up the dish, tower and antennas, then wait a couple weeks. Put up a yagi as well, pointed in the general direction of the neighbor, just for fun. When the complaints start rolling in, invite the authorities over and show them that nothing is connected to the antennas
old trick. works to discredit neighbors who complain needlessly.
Alot of those ships are getting old. Enterprise is 51 years old. Nimitz is 45 years old. If you stop building them, the number of carriers will naturally drop through attrition as the older ships are retired. There's a problem though: There is one and only one shipyard capable of building nuclear supercarriers. It's not a cargo ship. It's not a cruise liner. It's not even a normal naval vessel. It's a floating, nuclear powered, military city with a hanger and an airstrip on the upper decks. If you don't keep that yard busy building a ship every 5 or 6 years, you lose the ability to build them entirely. Why? Because all the people with the knowledge necessary will be looking for new jobs. When you do decide to build one, you'll be restarting from ground zero; and, it will cost significantly more to build that one than to have just kept the system running at a slow but steady pace. That's the argument anyway.
That depends on how fast it needs to get somewhere. Carriers often out run their non-nuclear support ships, when they push hard. Might seem counter-intuitive, being as big as they are; but, a carrier is a fast moving ship when she need to be.
If you're having to ask, you don't really want to go. If you like your current job, 10% isn't enough to justify leaving unless you have something else significant prompting your move. It sounds like your current employer is interested in your career development and willing to cultivating you. If you are in good graces with your current employer, what you might do is go to your manager and say something like:
"Look, I really like it here. But I have this other job offer that came out of the blue and they're offering me 10% more than I'm making here. I'd like to stay, can you match the other offer"
If they're serious and value you, they should make you a reasonable counter offer.
Slashdot Mirror
Aliens from Independance Day. Essentially swarms of inter-stellar locust, consuming all natural resources on a planet, then moving on...
Maybe. But maybe it takes so much energy to bring the other power sources to fruition that you need a massive source of energy to begin with; and, it's only worth the effort to power things like ships that need more compact energy sources.
Taking a cue from science fiction: If I remember right, in Star Trek lore, the Federation gets it's supply of anti-matter from a particle accelerator built on a platform in close orbit of Sol. It extracts the energy necessary to run the process from the star. It's not efficient; so, the only place it's worth using is to power starships. They use more mundane methods to generate power for use on the planet surface.
Hell, it would give us something to start beaming signals at like mad in the hope of a return at the very least.
You should be careful what you ask for. There are things you really shouldn't poke with a stick -- Bears for one, large cats, wasp nests, hives of locusts... Aliens advanced and hungry enough for raw energy (and materials) to build Dyson spheres.
OK, there are two issues here to discuss...
You could certainly build fusion power plants. Lots of them. As your power requirements go up as a society, you just build more. Except... The waste heat. No power generation process is 100% efficient. In fact, 30% may be a reasonable number for a nuclear plant. The remaining 70% becomes waste heat dumped into the environment. Now, what happens to the electrical energy you made -- the 30%? Some of that will get turned into "stuff" or into forms of potential energy. A substantial fraction will likely get converted into heat. So, as you build more and more power plants, you put more and more heat into the environment. You can already see this in localized heating of rivers where power plants draw water for cooling. If society becomes orders of magnitude more energy intensive than we are now, the heating of the environment could become a significant problem; and, the same would apply to any hypothetical advanced alien society.
As to where you get the material to build a Dyson sphere... To begin with that's a misnomer. No one would build a sphere -- they'd build a ring or a large number of orbiting platforms. As you pointed out, the solar system is vast. If your society is becoming advanced enough, large enough and energy intensive enough that you might consider a Dyson sphere, then you're probably going to have (or be able to develop) the ability to mine the non-habitable planets, asteroids, etc. for the raw materials you need.
It's very simple... NASA offers $51 million. Another party offers several million more. U.S. wants Russia to embrace capitalism; so, they do. How can we argue with that? We'll just have to hitch a ride on the next bus. Remember when you were a kid and had to borrow your parents car? You don't like the rules, buy your own.
Yes, yes. I'm aware there are services that will print you off a unique part from a CAD model -- the company I work for has used them. They're using one of the 1/2 dozen commercial machines, cost to purchase running 6 figures. What I meant was I'd like to see a machine available at a low cost.
You keep using that word. I don't think that word means what you think it means.
Not talking about rail as in railroad...
No, speed^2 * mass = kinetic energy.
That's one way to go, but the same could be said of the additive manufacturing machines that use plastics -- why not just make a mold and pour molten resin or a two part mixture like epoxy or polyurethane. Another issue: making a metal part in a mold requires you have a kiln capable of melting the base metal and are willing to pour molten metal in your workshop. Not everyone wants to do that kind of hot work
Truth be told, for my applications, I could simply throw a block of metal on a mill and make the parts I want -- and that's what I currently do. There are complex shapes that can be made with an additive process that can't be readily done with a subtractive process or by molding a single piece. So you end up making multiple parts and assembling the components.
I'm envisioning a device that lays down layers of powder and sinters it with a laser. Yeah, I know it is commercially available but I don't want to spend 6 figures on the machine, just to play around and make small parts. I'd like to see one with cost on the level of a few thousand dollars. I don't care how slow it is... I can wait a day or two for a part. Seems like I've convinced myself to try to build one.
sanded? More likely ground. You won't be able to make small parts using a wire feed welder.
That's a reasonable idea if you can live with how coarse the results might be. minimum line width would be the weld seam width, which depends on the power, feed speed, and the wire diameter; and, control of position would depend on how consistently the arc stays on the line. You would also need a compatible metal base to start with -- You have to weld to something substantial enough to strike an arc on and maintain the arc, without blow-through, until you build up a couple of layers.
Right now all the cheap ones are only capable of making plastic parts. I'd like to see a low cost metal powder additive machine. I don't care if it's aluminum or titanium (cheap or expensive) base metal.
Yeah, that's a great idea. We'll declare war on a species that already has at least a basic mastery of space travel... All they'd have to do is drop a couple of asteroids on us, liquify the Earth's crust and it would be all over.
And that music... Why oh why do TIE Fighters transmit such loud music? Would seem to negate any hope of stealth attack, with the theme music announcing their presence.
"It's a cookbook!" "A cookbook!"
damn. and I was having fun with that one too. Wish /. allowed editing.
Of course they're cutting funding. Green Banks has come close to finding the aliens living in orbit around a couple of nearby stars on several occasions. Damn close. The government needs to cut funding to prevent identification of the aliens --- the powers that be are aware of the aliens and know what kind of retribution they will bring on the Earth if humans become aware of "other" species existence. There has been very limited contact through Air Force satellites. The aliens have made their intentions very clear: As long as we remain a quaint backwater planet with no ability to travel off the small rock we live on, we are not a threat. As soon as we become a threat, the simplest course of action is to exterminate all life on the planet (that would be us). If Green Banks manages to identify the aliens, noone will be able to keep it quiet. It will drive interest in space exploration, funding for the space program, development of space vessels and then the genie is out of the bottle, so to speak. It cannot be allowed to happen. So, it is the Government's intention to quash funding for NRO and NASA, for the preservation of the human race.
late posting... Yeah I know, I live down the street from Newport News Shipbuilding, which is building the replacement.
que Homer voice:
Mmmmmmm. Electronics.
GSA was doing auctions decades before Ebay existed.
not shaving my beard. It's only just starting to show grey...
Almost there but not quite. First step is to put up the dish, tower and antennas, then wait a couple weeks. Put up a yagi as well, pointed in the general direction of the neighbor, just for fun. When the complaints start rolling in, invite the authorities over and show them that nothing is connected to the antennas
old trick. works to discredit neighbors who complain needlessly.
Alot of those ships are getting old. Enterprise is 51 years old. Nimitz is 45 years old. If you stop building them, the number of carriers will naturally drop through attrition as the older ships are retired. There's a problem though: There is one and only one shipyard capable of building nuclear supercarriers. It's not a cargo ship. It's not a cruise liner. It's not even a normal naval vessel. It's a floating, nuclear powered, military city with a hanger and an airstrip on the upper decks. If you don't keep that yard busy building a ship every 5 or 6 years, you lose the ability to build them entirely. Why? Because all the people with the knowledge necessary will be looking for new jobs. When you do decide to build one, you'll be restarting from ground zero; and, it will cost significantly more to build that one than to have just kept the system running at a slow but steady pace. That's the argument anyway.
That depends on how fast it needs to get somewhere. Carriers often out run their non-nuclear support ships, when they push hard. Might seem counter-intuitive, being as big as they are; but, a carrier is a fast moving ship when she need to be.
If you're having to ask, you don't really want to go. If you like your current job, 10% isn't enough to justify leaving unless you have something else significant prompting your move. It sounds like your current employer is interested in your career development and willing to cultivating you. If you are in good graces with your current employer, what you might do is go to your manager and say something like:
"Look, I really like it here. But I have this other job offer that came out of the blue and they're offering me 10% more than I'm making here. I'd like to stay, can you match the other offer"
If they're serious and value you, they should make you a reasonable counter offer.