All true. In fact for a LOX/RP1 rocket the savings is about a factor of 10 or so. Then add the fact that you can have vacuum nozzles all the way so performance is pretty close to optimal.
Hmm.. Good point. We a quick BOTE calculation gives me a release altitude (from earths center) of almost exactly 30000km. Release velocity is 2181m/s and would need a circulation delta V of 2244 m/s. Unfortunately i did the target altitude of 6400km. So you would in practice need to release a little higher, but the delta V must be less than LEO to GEO so its about right. Plane changes hit you of course but if you do that as soon as you release its an extra ~4km/s delta V max, so a total delta V of ~6km/s to any earth orbit, while many will be about half that. Quite a bit less than the 7-8km/s needed from earth surface. However you still need rockets!
Although i don't quite buy it will always be bullshit, there are few more issues than you mentioned.
Not only do we not have the structural materials yet, they may not be possible. Bulk strength of macroscopic samples are way to weak currently than the >60GPa required. Note however that is could be possible. At this stage we don't know.
Micro meteorites is often never mentioned. The fact is that CNT would have a *lot* of energy stored under the kind of tension needed. When broken that energy has to go somewhere. "Rip stop" does not even begin to solve this issue. Even a micro meteorite could cause a cascading failure.
Long term radiation damage. The cable would have a very finite life span. Maybe far to short to ever make it economically viable.
Mono atomic oxygen in the upper atmosphere is very reactive. Against carbon even more so.
Its a railway track between just two places. Its is not useful to get to other orbits, or is of limited use for other orbits.
Actually no. A space elevator is a bit like a train track with only 2 stations at each end. If you want to go anywhere else, it is more or less useless. For example its almost totally useless for LEO. Well tbh it is totally useless for LEO.
Well not that i care much about pigeons, but clay pigeons are probably a lot harder to hit as they can move at a fair clip with a good launcher. So this is kind of a crab shoot, but with pigeons.
Most of the energy is in xrays. Lots of xrays. Close enough and you get shock heating and ablation of the surface layer of the target, launching a shock wave/debris into the ship.
The ranges of space battles will be measured in 1000 to 100s of thousands of km. ie light microseconds to seconds. At 2.4km/s it would take 11 hours to travel 100,000km or 1/3 the way to the moon. If we use projectile weapons it will be in the 100km/s speed range.
Licensing H.264 adds more than cost. It adds the restrictions of the license you must sign, and its a pretty long list. H.264 you need a license to encode, decode, and even for the transportation layer. Fanboys go on about how its free now, when its *only* free for non commercial *streaming* services. They can also change their mind on that too. Its in the license agreement you signed.
You know what else is in the agreement? A statement that MPEG-LA may not have all the relevant patents and any third parties that want fees is between them and you. MPEG-LA offer not indemnity or assurances.
Without FRAND, we end up with lame standards that tiptoe around patents.
With FRAND we end up with huge complex standards so that every engineer at the table gets at least one of their patents included in the standard. Just look at h.264, that just reads like a stack of patents. Also it is not reasonable to have licensing restrictions shoved down your throat. Things like being forced to include DRM, not being allowed to distribute versions with things like Firefox etc.
Its not even the same for everyone, since all the big players are the ones with the patents.
High fees are discriminatory but still permitted with FRAND. Since only bigger companies can afford it. It adds barriers to entry that the big players want.
Lets not repeat the Rambus fiasco or the GIF situation again. If you have patents on stuff and you want the stuff in a *standard* that could tie up data that you have a right to access, then Free licenses to all or get lost.
Solar is not cheaper than coal for two simple reasons. It is not noon 24 hours a day 7 days a week without clouds and the land you put it on is not free and neither is the cabling and switching of the power.
Lets run some basic numbers: lets assume 20% solar cells (pretty high) and lets assume 24 hour noon sun 7 days a week without clouds. At the equator that gives us about 160W per m2. So we need 188000m^2 of solar panels, or 18.75Ha, or a square 433 meters on each side completely covered in panels. Only thing is that facebook goes down after noon, or when its cloudy or in the winter or if the panels are not at the equator. Now factor all that in, add some extra capacity, storage and cabling and you quickly see how solar is *not* cheaper than coal.
The cost of solar power is *not* just price per watt at optimal illumination.
?? what? I have many linux boxes here with a range of nvidia cards. They all run at about the correct speed. As in at full speed with the expected performance you would get in windows.
Of course many of the mobile cards do have low expected performance... and are not cheap either. You pay for small or power saving it seems... But then laptops are not really where high performance gaming is at regardless of OS.
Linux... It gives you linux. Steam is not on linux yet if ever. There was a time i would reboot to windows to play games. I don't anymore. So these guys do get money out of me because i can get some linux games. Steam does not. However if they where to offer a linux client and had some of their games available on linux.....
As for why OS is better? Well in this case it means linux distro devs can fix bugs and keep it working if they care enough.
You can go above iron as well. Adding a single proton or neutron to most elements above iron still gives a net energy output. Quite a bit of output too.
D+D fusion produces T. Tritium has a half of about 12 years and decays via a low energy beta decay. Its not totally harmless or anything, but its pretty safe over all because of its low energy decay, and because it doesn't accumulate in any one organ if it does become bio available. However is a real bitch to keep contained.
Neutron activation is perhaps a bigger problem. When we get fusion working, using low Z elements should allow for pretty short half life activation products. So the structure would be safe in weeks to a few years. A poor choice of materials is probably still safe after 20 years or so.
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All true. In fact for a LOX/RP1 rocket the savings is about a factor of 10 or so. Then add the fact that you can have vacuum nozzles all the way so performance is pretty close to optimal.
And how is that going to give you the delta V you need to go into a different orbit *not* anywhere near the elevator? You need rockets/reaction mass
It a day of wrongs for me today... not sure what that has to do with my primary school teacher though.
Turns out i am completely wrong about the last point. More or less.
Angular momentum is conserved. To spin something, something else must be spun the other way, or you need reaction mass.
Typos for the win. That should say a total delta V of ~6km/s to any *low* earth orbit. The rest i am sure readers can work out.
You are right. Sort of, see this post and my reply. Basically if you release to low, you just fall to earth. So you need rockets.
Hmm.. Good point. We a quick BOTE calculation gives me a release altitude (from earths center) of almost exactly 30000km. Release velocity is 2181m/s and would need a circulation delta V of 2244 m/s. Unfortunately i did the target altitude of 6400km. So you would in practice need to release a little higher, but the delta V must be less than LEO to GEO so its about right. Plane changes hit you of course but if you do that as soon as you release its an extra ~4km/s delta V max, so a total delta V of ~6km/s to any earth orbit, while many will be about half that. Quite a bit less than the 7-8km/s needed from earth surface. However you still need rockets!
Although i don't quite buy it will always be bullshit, there are few more issues than you mentioned.
Not only do we not have the structural materials yet, they may not be possible. Bulk strength of macroscopic samples are way to weak currently than the >60GPa required. Note however that is could be possible. At this stage we don't know.
Micro meteorites is often never mentioned. The fact is that CNT would have a *lot* of energy stored under the kind of tension needed. When broken that energy has to go somewhere. "Rip stop" does not even begin to solve this issue. Even a micro meteorite could cause a cascading failure.
Long term radiation damage. The cable would have a very finite life span. Maybe far to short to ever make it economically viable.
Mono atomic oxygen in the upper atmosphere is very reactive. Against carbon even more so.
Its a railway track between just two places. Its is not useful to get to other orbits, or is of limited use for other orbits.
Only thing is that 96000km is a third of the way, not a quarter.
Actually no. A space elevator is a bit like a train track with only 2 stations at each end. If you want to go anywhere else, it is more or less useless. For example its almost totally useless for LEO. Well tbh it is totally useless for LEO.
Well not that i care much about pigeons, but clay pigeons are probably a lot harder to hit as they can move at a fair clip with a good launcher. So this is kind of a crab shoot, but with pigeons.
I am interested in what action movie would be "A grade" since by definition a action movie is well.. not really driven by plot.
Most of the energy is in xrays. Lots of xrays. Close enough and you get shock heating and ablation of the surface layer of the target, launching a shock wave/debris into the ship.
The ranges of space battles will be measured in 1000 to 100s of thousands of km. ie light microseconds to seconds. At 2.4km/s it would take 11 hours to travel 100,000km or 1/3 the way to the moon. If we use projectile weapons it will be in the 100km/s speed range.
There ain't no stealth in space. The site has a lot more interesting things about the topic at hand.
Licensing H.264 adds more than cost. It adds the restrictions of the license you must sign, and its a pretty long list. H.264 you need a license to encode, decode, and even for the transportation layer. Fanboys go on about how its free now, when its *only* free for non commercial *streaming* services. They can also change their mind on that too. Its in the license agreement you signed.
You know what else is in the agreement? A statement that MPEG-LA may not have all the relevant patents and any third parties that want fees is between them and you. MPEG-LA offer not indemnity or assurances.
Without FRAND, we end up with lame standards that tiptoe around patents.
With FRAND we end up with huge complex standards so that every engineer at the table gets at least one of their patents included in the standard. Just look at h.264, that just reads like a stack of patents. Also it is not reasonable to have licensing restrictions shoved down your throat. Things like being forced to include DRM, not being allowed to distribute versions with things like Firefox etc.
Its not even the same for everyone, since all the big players are the ones with the patents.
High fees are discriminatory but still permitted with FRAND. Since only bigger companies can afford it. It adds barriers to entry that the big players want.
Lets not repeat the Rambus fiasco or the GIF situation again. If you have patents on stuff and you want the stuff in a *standard* that could tie up data that you have a right to access, then Free licenses to all or get lost.
Solar is not cheaper than coal for two simple reasons. It is not noon 24 hours a day 7 days a week without clouds and the land you put it on is not free and neither is the cabling and switching of the power.
Lets run some basic numbers: lets assume 20% solar cells (pretty high) and lets assume 24 hour noon sun 7 days a week without clouds. At the equator that gives us about 160W per m2. So we need 188000m^2 of solar panels, or 18.75Ha, or a square 433 meters on each side completely covered in panels. Only thing is that facebook goes down after noon, or when its cloudy or in the winter or if the panels are not at the equator. Now factor all that in, add some extra capacity, storage and cabling and you quickly see how solar is *not* cheaper than coal.
The cost of solar power is *not* just price per watt at optimal illumination.
?? what? I have many linux boxes here with a range of nvidia cards. They all run at about the correct speed. As in at full speed with the expected performance you would get in windows.
Of course many of the mobile cards do have low expected performance... and are not cheap either. You pay for small or power saving it seems... But then laptops are not really where high performance gaming is at regardless of OS.
Why do you need to switch? I think you can use both.... If Desura has a game you really want, you don't have to dump all your steam games.
Linux... It gives you linux. Steam is not on linux yet if ever. There was a time i would reboot to windows to play games. I don't anymore. So these guys do get money out of me because i can get some linux games. Steam does not. However if they where to offer a linux client and had some of their games available on linux.....
As for why OS is better? Well in this case it means linux distro devs can fix bugs and keep it working if they care enough.
In what way was it debunked? By the fact that the western world didn't grind to a halt?
You can go above iron as well. Adding a single proton or neutron to most elements above iron still gives a net energy output. Quite a bit of output too.
D+D fusion produces T. Tritium has a half of about 12 years and decays via a low energy beta decay. Its not totally harmless or anything, but its pretty safe over all because of its low energy decay, and because it doesn't accumulate in any one organ if it does become bio available. However is a real bitch to keep contained.
Neutron activation is perhaps a bigger problem. When we get fusion working, using low Z elements should allow for pretty short half life activation products. So the structure would be safe in weeks to a few years. A poor choice of materials is probably still safe after 20 years or so.