tag:blogger.com,1999:blog-189672512024-03-07T05:56:13.652-08:00Solar EmpireMy personal soapbox for thoughts on space exploration, politics, and anything elseqwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.comBlogger67125tag:blogger.com,1999:blog-18967251.post-52517868712153863022011-01-25T09:20:00.000-08:002011-01-25T09:24:20.695-08:00New Neutrino Telescope<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuxaNsaS1xcoMvTKXKENlGfD5q8O2yzlei3sXQvaAnAs60EGwBg3kaMYrByjQV3N_sAg6ru4YE2xy0uGSbhamlBBt_Dg0IxzDP9nqVjHgqPkzKzEngK28ICNkQWBYqqHRBMXzIzg/s1600/IceCube-schema.jpg"><img id="BLOGGER_PHOTO_ID_5566175282828121458" style="DISPLAY: block; MARGIN: 0px auto 10px; WIDTH: 320px; CURSOR: hand; HEIGHT: 259px; TEXT-ALIGN: center" alt="" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhuxaNsaS1xcoMvTKXKENlGfD5q8O2yzlei3sXQvaAnAs60EGwBg3kaMYrByjQV3N_sAg6ru4YE2xy0uGSbhamlBBt_Dg0IxzDP9nqVjHgqPkzKzEngK28ICNkQWBYqqHRBMXzIzg/s320/IceCube-schema.jpg" border="0" /></a>Apparently one of the newer NASA science projects is a 1.5 mile long neutrino detector, called Ice-Cube. In the antarctic, they will drill 86 holes, 2820m deep down to bedrock, and lower strings of detectors down the length of the hole.<br /><br />Neutrinos are particles produced in fusion reactions. Neutrinos and antineutrinos are the chargeless analogs of electrons and positrons, and only interact with other matter via the weak nuclear force. Because the weak nuclear force is very weak, it is very improbable for neutrinos to interact with anything.<br /><br />It is so rare that they interact that the Earth is largely transparent to their passage. Prior neutrino detecting experiments were built deep beneath the earth to block out all other forms of radiation. These detectors built up an image of the mantle of the sun: at midnight, on the other side of the world.<br /><br />I imagine that NASA is interested in this telescope to probe deep into the heart of energetic phenomena like quasars. The gas, dust, and accretion disks would be transparent to neutrino passage, and you would see straight to the heart of fusion processes. <div><div><br />I wonder though if this is a telescope in the sense of being able to build up a focused image from the data, or if it can only build up a defocused accumulation of neutrino magnitude as a function of direction? After all, if a neutrino interacts with the top detector, it would be very amazing odds for it to interact with any of the others prior to flying out into space, even without taking into account the scattering nature of the detection.<br />Still cool regardless. We live in amazing times.<br /></div><div>Source Article: <a href="http://www.networkworld.com/community/blog/massive-ice-bound-telescope-set-capture-elusi" mce_href="http://www.networkworld.com/community/blog/massive-ice-bound-telescope-set-capture-elusi">http://www.networkworld.com/community/blog/massive-ice-bound-telescope-set-capture-elusi</a><br /></div><br /><div>PS:<br /><span style="color:#cc0000;">Future professor: You failed your quals! To encourage a proper studious attitude for the retake, I <strong><em>banish you to the ice telescopes of Antarctica!</em></strong></span><br /><span style="color:#33ff33;">Future grad student: Nooooo!</span></div></div>qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com3tag:blogger.com,1999:blog-18967251.post-11655532998579384862011-01-24T16:50:00.000-08:002011-01-24T16:53:11.295-08:00New WebblogI have a new webblog site at <a href="http://www.amssolarempire.com/Blog">http://www.amssolarempire.com/Blog</a><br /><br />I am going to try going semi-professional here, and restart my blogging on a wordpress website. I’ll have more control, than with blogger, and I will also be able to use the site as a point of distribution for coding projects, files, and tutorials. This will enable me to share my projects more effectively.<br /><br />Going forward, I hope to share my knowledge and enthusiasm for science and aerospace technology, and space exploration on a regular basis again.<br /><br />I will attempt to duplicate posts on each site, at least for now.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-34742502213919106322009-04-12T19:25:00.001-07:002009-04-12T19:26:17.167-07:00KeepaliveI do intend to keep this blog. After my term of employment, I should be allowed to blog again, and will resume. This post is to keep any automatic cleanup routine from deleting my blog.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com2tag:blogger.com,1999:blog-18967251.post-68680686314097133852007-04-29T16:21:00.000-07:002007-04-29T16:43:20.177-07:00Math Blues IGaaah.<br /><br />So I'm trying to figure out a bit about wave dynamics - namely how a wave can move in a collimated fashion, such as in a light ray or laser beam.<br /><br />I was playing around with the wave equation a bit. I set up field sims for a 3d wave and advanced time, reproducing all sorts of interesting effects. Diffraction, reflection, interference, refraction ect.<br /><div align="center"><br /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjRcdfB0qLqJTmUeg_e_ENX8NS9u4xWtCWDjUJuToK4lpCNseI9rLN68w4m297Aw4OgJsTfM__p7Xah8Fizo4TFcOifiwKJGWvpMIK_7eQC5gZqZ5BSIIy5RT1s6HpVhI9P8sFvUA/s1600-h/bla5.bmp"><img id="BLOGGER_PHOTO_ID_5058999196980223842" alt="" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjRcdfB0qLqJTmUeg_e_ENX8NS9u4xWtCWDjUJuToK4lpCNseI9rLN68w4m297Aw4OgJsTfM__p7Xah8Fizo4TFcOifiwKJGWvpMIK_7eQC5gZqZ5BSIIy5RT1s6HpVhI9P8sFvUA/s320/bla5.bmp" border="0" /></a><br /><br /></div><br /><br />Then something started bugging me - if you have a travelling wave, how do you get it so that it retains a collimated shape? It seems to me that the divergence of the gradient on a point outside the beam is going to be nonzero due to the difference between the zero and nonzero amplitudes inside and outside the beam, and so the region outside the beam should be sucking up energy and spreading the wave as it travels.<br /><br />At first I thought it was just that I was looking at a scalar wave, and light is a more complicated vector wave operating off of different rules. But in my optics book, they eventually transform maxwells equations into a set of 6 scalar equations for the electric and magnetic field, and the same laplacian(field) = acceleration(field) behavior results.<br /><br />Okay, so then I did some reading and discovered that beams usually have gaussian distribution of amplitude along the beam radius.<br /><br />I want to be able to figure out how the amplitude's radial profile changes as you move along the wave. So I wanted to transform the wave equation into a different coordinate system moving with the beam.<br /><br />laplacian(field(x,y,z)) = acceleration(field(x,y,z)) -> acceleration(field(x-vt,y,z)) = ???<br /><br />and here's where I have to quit for today, I need to make dinner.<br /><br />This better not be something that some old math god fart like Newton or Euler solved in 5 minutes while waiting for the coffee to brew.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com4tag:blogger.com,1999:blog-18967251.post-46882646228752775772007-04-24T16:43:00.001-07:002007-04-24T17:18:47.843-07:00Amazing! Amazing! Amazing!In the red-dwarf star system Gliese 581 (20 ly from the Solar System), a (probably) rocky planet has been discovered. It is orbiting within the region of the star system where liquid water can form. (It is a much closer and smaller band than exists in our own star system, but apparently this planet falls within it).<br /><br />It just might be the first earth-like planet we've discovered (after our own, of course)!<br /><br /><a href="http://www.zeenews.com/znnew/articles.asp?aid=367459&ssid=27&sid=ENV">http://www.zeenews.com/znnew/articles.asp?aid=367459&ssid=27&sid=ENV</a><br /><br />The planet is estimated to be 50% larger than Earth. Furthermore, red dwarf systems are very long lived, so if there is liquid water on this planet, there is also a good time window for life to have formed (or form, later on).<br /><br /><a href="http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=450467&in_page_id=1965">http://www.dailymail.co.uk/pages/live/articles/technology/technology.html?in_article_id=450467&in_page_id=1965</a>qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com5tag:blogger.com,1999:blog-18967251.post-547969222368978222007-04-12T03:44:00.000-07:002007-04-12T16:33:52.164-07:00Crazy Nuke Idea #1I don't know enough nuclear physics (yet - I intend to know everything someday, though I also understand on an intellectual level why this is impossible) to tell if this is a good idea or not, but I was thinking:<br /><br />(digression)<br />The holy grail of nuclear power physics is nuclear fusion. Presumably we would never have to worry about energy again if we had fusion reactors. I think people assume this because of the abundance of hydrogen in the universe. While it's true that hydrogen is the most abundant element in the universe, we don't have any shortage of uranium or thorium (on earth).<br /><br />However, these reactors appear to me to be extremely complicated rube goldbergs compared to the simplicity of our fission plants. They require giant magnetic plasma traps to keep plasma spinning in large evacuated chambers. They require creating enough fusion reactions with this plasma to allow for drawing enough energy off of it (how? I've heard either thermally or through some sort of magnetic induction) to turn some sort of electric generator to feed enough power back into the magnets to keep the reaction going. So far, we don't seem to have reached anywhere near enough fusion/input energy to get this to work. While I've read about reaching breakeven for scattered microseconds on research devices, it doesn't appear that we've reached it on average for any extended period of time on a device.<br /><br />Furthermore, even when we get it to work, building and operating these plants sounds like a pain in the butt. You have an extremely unstable reaction that could stop sustaining itself if anything goes out of whack. You have massive construction costs for the magnetic coils and vacuum chambers. You probably have massive operating costs because of the attention that these devices will require by plasma physicists.<br /><br />So … I don’t know how often I’ve heard the sentiment expressed: Fission is old, inefficient (??? Efficiency needs a lot of qualifiers to mean something, you know), and dirty. Fusion is clean, efficient (???), and much much better. It is the way of the future.<br /><br />Why this sentiment if 1) We can’t get it to work yet, 2) When we do get it to work, it will almost certainly be more complicated and expensive to operate, even taking insane regulation of fission and the need to process the waste into account. It’s almost like hearing “SSTO Reusable Spaceplanes are the Wave of the Future ™” over and over again, when I know why they can’t work.<br /><br />Furthermore, where nuclear fission reactors have been scaled to some extent to fit in all sorts of situations (silent power for submarines, the ability to push the navy carriers around in the ocean without a direct oil pipeline back to shore, experimental rocket engines, proposed remote mini-reactors, ect) I’m not sure if a tokomak can scale that easily. You need to hit that reaction/reactor ratio before you can produce power.<br /><br /><br />If we ever do get fusion power to work, then cool. There are many planets in the solar system that don’t have heavy metals like uranium available in the quantity that they are here on Earth. If we had a tool like that under our belt, we would never run out of fuel in the lifetime of the universe. I just don’t see how, if you’re a city manager with a situation where you have ready access to uranium, you make the decision to build something 10x more complicated and expensive than you have to.<br /><br />(/digression)<br /><strong>That said, here’s my crazy idea:</strong><br /><br />These tokomaks are trying to collide light elements together with sufficient energy to cause a fusion reaction. Light elements usually have high proton to neutron ratios, meaning that they have low mass/charge ratios. The nuclei will tend to veer away from each other, unless they are traveling at each other with large velocity and angular precision.<br /><br />Heavy elements, on the other hand, have much lower proton to neutron ratios. How much easier would it be to collide heavy nuclei in a heavy ion plasma with the intention of fissioning the nuclei than to attempt fusioning light nuclei? Could you sustain a tokomak fissioning a heavy ion plasma where you couldn’t sustain it with a fusioning plasma?<br /><br />Variation #2:<br /><br />Current fission reactors use fissile uranium (U-235), however there is something like 100x more U-238 (the stable uranium isotope) in naturally occurring uranium.<br /><br />Furthermore, thorium, a lighter element, is being looked at because its reactions don’t result in elements heavy enough to be used in nuclear weapons. If you used some sort of reactor based primarily on thorium, you wouldn’t have to worry about proliferation. You could trust this technology to anyone without worrying if they’ll convert it over to producing nuclear weaponry. Thorium also happens to be even more abundant than uranium.<br /><br />Currently the thorium reactions are being sustained by uranium rods, because the thorium won’t sustain the reaction on it’s own. Not enough neutrons created and absorbed per reaction to keep the thing going.<br /><br />I’m wondering if it’s possible to sustain a thorium fission reaction by firing a beam of heavy ions through the material. Heavy fast ions collide with thorium nuclei -> nuclear chaos happens -> maybe enough neutrons are generated to trigger enough reactions to make the rod hot? Could you generate enough energy from the reaction to run the particle accelerator sustaining it? If so, you could have a reactor that<br /><br />1) Could never melt down because it requires active input to sustain the reaction (but not quite as much active input as required to run a fusion reactor) (though modern uranium reactor designs also can claim this feature)<br />2) can’t be used to make nuclear weapons material<br />3) might be more economically competitive because it doesn’t need as heavy a containment dome (possibly doesn't need one at all) No danger of internal superheated metal or high pressure steam, if the whole thing can be regulated by the particle accelerator breaking/turning off. No inspectors or guards to keep the materials out of terrorist hands.<br /><br />I wonder if it could be scaled down enough to use on a car, or in a home? Maybe a nuclear powered aircraft that doesn’t need gasoline and has no range limitations?…<br /><br />I’d love to see the nuclear revolution re-started after the hysteria of the 70s. I’d love to see this powerful, compact, nearly endless source of energy powering our cities, factories, ships, and spacecraft (you can do a lot with a nuclear rocket engine). The “energy crisis” (we’re running out of oil) or “carbon crisis” (we use too much oil), these hysterical <em>(even longed for by some fanatics)</em> visions of mankind being forced back into a cowed, limited, pre-industrial agrarian zero-sum state (with solar panels) doesn’t make any sense at all with nuclear energy firmly in our grasp. The most maddening thing about it is that it almost was, and that what keeps us from using it isn’t any engineering or technological hurdle, but entirely self-imposed legal limitations!qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com3tag:blogger.com,1999:blog-18967251.post-33126744574622533762007-04-05T19:50:00.000-07:002007-04-05T19:54:37.447-07:00Is this real?<a href="http://health.howstuffworks.com/extracellular-matrix.htm">http://health.howstuffworks.com/extracellular-matrix.htm</a><br /><br />Extra-cellular matrix material triggering regeneration. I wonder, is this just woo-woo nonsense, or real? What is the screening process for howstuffworks.com?<br /><br />You have to have a deep suspicion about claims for "alternative" anything these days. So much of it is just superstitious credulous nonsense promoted by charlatans and cranks.<br /><br />But if it's real ... cool. One step forward for medical science.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-44098846635132107332007-04-04T19:08:00.000-07:002007-04-06T17:54:23.676-07:00Eruption on IoThis shows an eruption on one of Jupiter's moons, Io.<br /><br /><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjRzX4ZmljPsYk6wHKu43tUBNVcGTemcKoFvoubItoHsM4YPcO0GwvFRe8oLFBzxhdCR_ynpYiB606GK9CPNmvhqOVNwIud-U6SkAnSGGMHL5P6f069L8lAGMojjER9aVfbraZJLw/s1600-h/iovolcano0x01.jpg"><img id="BLOGGER_PHOTO_ID_5049762075636748050" alt="" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjRzX4ZmljPsYk6wHKu43tUBNVcGTemcKoFvoubItoHsM4YPcO0GwvFRe8oLFBzxhdCR_ynpYiB606GK9CPNmvhqOVNwIud-U6SkAnSGGMHL5P6f069L8lAGMojjER9aVfbraZJLw/s320/iovolcano0x01.jpg" border="0" /></a><br /><br />It is cool, isn't it?<br /><br />Picture shamelessly stolen from <a href="http://www.cosmicconservative.com/">http://www.cosmicconservative.com/</a>qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-37786146864425563532007-03-29T05:15:00.000-07:002007-03-29T05:21:00.728-07:00CookingI've managed to cook some of my first meals last weekend. It's actually kind of cool really. And it tastes much better than microwave meals. I don't cook every night, for time constraints. But my plan right now is to cook enough on the weekends to last me through some of the meals throughout the week.<br /><br />The first thing I made was beer and bratwurst. You need 2 beers, an onion, and a package of bratwurst. Put the bratwurst in the pan, chop up the onion and put that in the pan, pour one beer in the pan and turn the heat to medium until the beer and onions cook down to a syrup. Use the other beer with dinner.<br /><br />The second thing I made was sausage and peppers (surprisingly good for something so simple). Take an onion, one or two peppers (a green and a colored one), chop them up and put them in the pan. Put a can of tomato paste in the pan. Fill it back up with water and put some water in the pan. Put some italian sausage in the pan. (Put a lid over the pan! A little bit of a lesson learned there) Cook that on medium for an hour and a half or so.<br /><br />And remember, don't make the mistake I did of putting non-stick cookware in the dishwasher!qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-77653323990520629862007-03-29T04:58:00.000-07:002007-03-29T05:05:39.577-07:00New Political Blog...by your favorite blog author.<br /><br />I've finally started my own political blog. After 3 or 4 years of contenting myself to lurk and comment on other's websites, I've given in to the urge to bloviate and vent my opinion for all to see.<br /><br />I've been blogging before this, of course, on <a href="http://amssolarempire.blogspot.com">http://amssolarempire.blogspot.com</a>, but I've tried to keep that blog low key on the political scale of things. And subjects that do get political, such as energy production, I've tried to back up as much as possible with numbers.<br /><br />I've done this for a few reasons. One of them is that I was still in college and didn't want to attract attention for political viewpoints.<br /><br />The other was that I had enough on my plate with engineering school, that I couldn't give my desire to opine on current events full reign. Time constraints prevented it, though the desire manifested as profuse commenting on other's blogs.<br /><br />A third is that I wanted my other blog to be palatable to people regardless of their politics. There are many people who I respect in terms of their opinion about space travel or science, whose political opinions I find batty. There are people who I agree with on many political issues, who start slinging opinions about science or history, or specific issues that I just stop and find myself on the opposite end of.<br /><br />So I'll keep up the policy of keeping the two blogs seperate. Those of you who want to enjoy my thoughts on space travel and colonization can still use my old blog, while avoiding wading through my rants. Those who don't mind the fact that I'm a rabid right-winger can peruse both as it suits them.<br /><br />And I'll welcome any intelligent debate. (Debate by making arguments and submitting information, not by slinging ad-hominems) I know, I know, everyone says this. But I'll try my best to live up to the claim.<br /><br />The new blog can be found at: <a href="http://soapboxzone.blogspot.com/">http://soapboxzone.blogspot.com/</a>qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-23889557962275630352007-02-17T13:27:00.000-08:002007-02-17T13:29:40.856-08:00Google Ate BloggerApparently I need a Google account to continue using blogger. Not too sure what all is involved in this. I don't really like Google, and stopped using them a few years ago because of their involvement in writing the censorship and spy software to police the Chinese internet. Whatever happened to "don't be evil"? That pissed me off, so I'll have to figure out what to do now.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-62945097524427497392007-02-17T13:23:00.000-08:002007-02-17T13:25:15.030-08:00Sight to the Blind!!!!!!Let’s give it up for the Doheny Eye Institute, Southern California, and whoever else worked on this project. This sort of thing really lifts my spirits. These people have laid the groundwork for technology that will restore sight to the blind! Particularly people with problems related to the retina, including macular degeneration and retinitis pigmentosa.<br /><br />They’ve developed an artificial retina implant that sends signals to the retinal nerves. This implant communicates by way of radio receiver to a small camera in a pair of glasses. So far, the resolution is pretty low, but I have confidence that if we can get mega pixels in a digital camera, they can figure out how to improve their system with time and development. They’re conducting medical trials now, for which thousands of people have already volunteered.<br /><br />It reminds me a bit about the motor cortex reader implant that I read an article about a year ago (don’t have the links…). Apparently another group of researchers managed to read the motor commands sent out by the area of the brain responsible for directing our movement. They could get a monkey to manipulate an artificial arm, or people to manipulate mice on a computer screen.<br /><br />Imagine how liberating this sort of technology will be for quadriplegics who cannot feel any part of their bodies, to be able to control something! Imagine how liberating it will be for the blind to see again! This sort of technological development is something I love to hear about. These guys deserve our investment and support.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1170331328071623952007-02-01T04:01:00.000-08:002007-02-01T04:02:08.480-08:00Question about Quantum Computing:Okay, so I’ve sort of started to grasp what quantum computing is and how it works (after comments from some of my co-workers the other day). And I hate not understanding certain things – if things are explained to me and I still don’t understand, it bugs me to no end; and I in turn usually bug them to no end with more and more specific questions until I begin getting it at a basic level. I think my internet research to date has given me a preliminary concept though and I’m going to put it up and ask a few questions about it.<br /><br />(Quantum physics stuff especially bugs me because people try explaining things like uncertainty or Bells inequality with buzzwords “multiple universes” and “superposition of concepts”, like “well sometimes it’s a particle and sometimes it’s a wave”. This doesn’t give me much of a picture of what’s going on, just a series of stories told about the topic. Someday I’m going to wade through an entire QP textbook, nasty field equations and all, just to keep myself sane when the topic comes up.)<br /><br />Okay, well here is what I’ve gathered about how quantum computing works so far: You start with some data that you want to perform operations on. There is some process whereby several bits of information are encoded in one or more “quibit” vectors. These vectors can be imposed (method unknown) on the state of things like fluorine atoms suspended at extremely low temperatures, ect; where we can preserve quantum superposition of these states. (Quibits being quantum superpositions of on-states and off-states, the superposition can hold the whole vector (with analog probabilities assigned to each vector basis) worth of information, rater than just digital on or off states.)<br /><br />Okay, so now you have many digital bits worth of information represented by the analog orientation of these quibit vectors. You can now perform other superposition operations between quibit vectors (addition, subtraction, and negation are apparently the limit. conditionals currently require us to collapse the state, reconvert the info, and digitally operate). You are effectively performing operations on all these different pieces of digital info simultaneously by adding the vectors.<br /><br />Then you reconvert the quibits back into digital information so that you can see what you have. Actually, when you collapse the superposition of states of a quibit you just get either 1 or 0. But when you send the info through multiple times, you get 1 with probability a and 0 with probability b, {a,b} being the components of the resultant quibit vector, which can be re-converted back into digital info using the reverse of your encoding method.<br /><br />(missing anything so far?)<br /><br />Okay, so this brings me to some of my questions:<br /><br />1. Maintaining superposition of states in fluorine atoms is a pain in the butt, requiring cool, yet bulky and expensive lab toys like near-absolute-zero temperatures and big NMRI machines to manipulate and read the state of the atoms. What would prevent you from doing the same operations with analog electric signals? If you have an analog signal a and b, you still have a 2d analog vector in which you can encode some number of digital bits and perform the same addition, subtraction, and negation operations. Furthermore, you don’t have to destroy the info (like you destroy quibits when you read them) to read an analog vector. One pass should give you the straight values of a and b, and thus the resultant vector.<br /><br />2. QCs are supposed to allow us to solve currently infeasible problems much faster than conventional computers due to our ability to encode some arbitrary amount of information in quibits which can be passed through simultaneously. However, can you do something like matrix inversion without conditionals? Gaussian elimination requires you to look at what you have several times to see what the magnitude of the leading values are in the row are. Other iterative methods of inversion require matrix multiplication. (Can you “multiply” information within a quibit without having to collapse it to read how many times to add another quibit?)<br /><br />To be continued.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com3tag:blogger.com,1999:blog-18967251.post-1167077755502994322006-12-25T12:09:00.000-08:002006-12-25T12:15:55.723-08:00Merry Christmas 2006!Merry Christmas! Hopefully everyone is having a wonderful holiday this year. We are, visiting family, making huge vats of egg-nog, giving gifts, ect.<br /><br />I'm getting a lot of stuff related to setting up an apartment. No more dorm room or microwaved coffee for me. Preparing food is getting more complicated, involving things like plates, metal silverware, sautee pans, and other assorted instruments.<br /><br />The reason for all this being: I'm done, I've graduated, and I'm off to a new career in the Air Force doing aeronautical engineering!<br /><br />(It's almost surreal being done with college. Up until two nights ago, I was still having nightmares about final exams! :-P )<br /><br />Anyway, have a merry Christmas. Good luck classes of December 2006 everywhere. ASBC class of 2006, I'll be seeing you in Alabama shortly.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-1166064356474344402006-12-13T18:43:00.000-08:002006-12-13T18:45:56.883-08:00Shooting Star 12-13-06I think I just saw a meteor or something. It went across the sky fast enough, about two seconds before winking out. Pretty neat. I don't look at the sky enough anymore, esp since you can't see squat from school.<br /><br />Now if it had been just 100 meters wider, it may have even made the news. (Evil laugh).qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1166035756811301522006-12-13T10:40:00.000-08:002006-12-13T10:49:48.123-08:00Doesn't Quite Handle Like an Airplane<a href="http://photos1.blogger.com/x/blogger/5111/1864/1600/453539/ASEILCL2.jpg"><img style="MARGIN: 0px 10px 10px 0px; CURSOR: hand" alt="" src="http://photos1.blogger.com/x/blogger/5111/1864/320/257747/ASEILCL2.jpg" border="0" /></a><br /><br />That is my new model Lunar Cargo Lander.<br /><br /><br /><a href="http://photos1.blogger.com/x/blogger/5111/1864/1600/813154/ASEILCL1.jpg"><img style="MARGIN: 0px 10px 10px 0px; CURSOR: hand" alt="" src="http://photos1.blogger.com/x/blogger/5111/1864/320/717733/ASEILCL1.jpg" border="0" /></a><br /><br />Here you see it hauling a standard EELV cargo can down to the lunar surface.<br /><br />The rationale behind the lander is that it takes cargo from low lunar orbit to a lunar base on the surface, and vice versa using in situ-derived propellants. (Some lunar in-situ propellant ideas use common lunar materials like powdered aluminum and liquid oxygen. They are easy to produce, but give you cruddy Isp.)<br /><br />The propellant tanks may be out of realistic scale, I'll have to do the math later.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1165982507416315702006-12-12T19:40:00.000-08:002006-12-12T20:17:18.150-08:00Launching into the solar system: Celestia Syle!Celestia is one awesome piece of free software. It's a planetarium where you can set up all sorts of scenarios, not to mention just view the solar system. If you download the extra high res textures from Celestia Motherlode, Earth and Mars especially begin to look very impressive.<br /><br />The software allows the placement of spacecraft, basing their appearance off of .3ds files.<br /><br />Not content to leave the simulated solar-system just glittering there in the simulated sky untouched, I downloaded one of the .3ds editors, Anim8or, off of Celestia Motherlode and have been launching my own "space-program".<br /><br />The things I find to unwind after exams....<br /><br /><br /><a href="http://photos1.blogger.com/x/blogger/5111/1864/1600/707011/GEOJaunt2.jpg"><img style="MARGIN: 0px 10px 10px 0px; CURSOR: hand" alt="" src="http://photos1.blogger.com/x/blogger/5111/1864/320/116055/GEOJaunt2.jpg" border="0" /></a><br />The long range personnel shuttle out for a GEO mission. If you look closely, you can even see some astronauts staring out the window. The belcher among the crew is being cycled out the airlock.<br /><br /><a href="http://photos1.blogger.com/x/blogger/5111/1864/1600/38210/ASEIStat1_1.jpg"><img style="MARGIN: 0px 10px 10px 0px; CURSOR: hand" alt="" src="http://photos1.blogger.com/x/blogger/5111/1864/320/196442/ASEIStat1_1.jpg" border="0" /></a><br />Here you can see my space station. Another of those long range personnel capsules is drifting nearby, along with two experimental engines.<br /><br />.3ds files and .ssc files will be posted laterqwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1165788608569516852006-12-10T14:05:00.000-08:002006-12-10T14:10:09.080-08:00Time to blog!Well, not quite yet, though I have a lot of things backed up that I'd like to blog about.<br /><br />First - my econ exam on Tuesday.<br /><br />But I'm almost out of the hole. Last week was a nightmare in terms of the deadlines and due dates and projects and multiple all-night meetings and......<br /><br />I'm coming down off a week-long caffiene high coupled with a complete lack of meaninful sleep. But I made it. I'm still intact. I retained my sanity (hee - hee .... hee). Now I need to pull out of school mode and focus on what's next: Commissioning! Graduation! The Air Force! Amazing to think that just one week from now, I'll have a BS in Astronautical Engineering and will be on my way to a real job. Just two days ago, my time horizon was measured in hours till CFD project due, and now it has to expand to encompass the next months of training.<br /><br />More to come soon.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1165505318086796542006-12-07T07:27:00.000-08:002006-12-07T07:28:40.376-08:00An Important Point about Freedom of SpeechAn important point about freedom of speech and the internet.<br />Link:<a href="http://denbeste.nu/entries/00000910.shtml">http://denbeste.nu/entries/00000910.shtml</a>qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1163986999680136502006-11-19T17:41:00.000-08:002006-11-19T17:44:20.173-08:00Random Quote 1Power corrupts, and the computing power to brute force any integral-differential equation corrupts absolutely. :-P<br /><br />Except when your teacher won't provide you with the probability function and wants you to solve it in general ... dang.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1163648571812811402006-11-15T19:39:00.000-08:002006-11-15T19:44:45.763-08:00Schoolwork!!!Aaaaagh! If you've wondered where I've been the past few weeks, it's been with my nose to a computer screen out at the Aero building or at home.<br /><br />I wonder what the minimum posting frequency is before blogger dumps your blog?<br /><br />Back to the grind. Thank God for coffee! Sometimes it's the only animating force in my body.<br />26 days or so to graduation!qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com0tag:blogger.com,1999:blog-18967251.post-1161390684960675352006-10-20T17:26:00.000-07:002006-10-20T18:08:30.366-07:00Misanthropy I<a href="http://davidszondy.com/ephemeral/2006/10/ozymandias.html">http://davidszondy.com/ephemeral/2006/10/ozymandias.html</a><br /><br />Here's a post, with which I wholeheartedly agree. It appears the misanthropes are at it again, this time of the eco-maniac variety.<br /><br />I sort of understand this misanthropy, where it comes from. It does not mean I sympathise. In fact, it's annoying, creepy, and indicative of a totalitarian mindset (mankind is not conforming to <i>my beautiful IDEAL</i>, and is therefore evil, hopeless, and worthless, and I will celebrate the day it is brought to its knees).<br /><br />I've come up against the same attitude again and again. In fact, I'm going to have to invent or find a word to classify these recurrent themes which I encounter repeatedly in the thinking of others.<br /><br />For example, just today on some random post about fads on an astronomy board, someone posted the following:<br /><br /><em>"You get blasted with carefully constructed psychological manipulation that promise the next piece of rubbish you buy will finally give meaning to your life. And because most people don't have any meaning in their lives, they are desperate enough to keep falling for it." </em><br /><br />Because most people don't have any meaning in their lives. Oh no. Their lives are meaningless. Worthless. Plodding. Monotonous. Why, they go about buying things that <em>amuse </em>them, or <em>please </em>them, or that they think they "need" (a ridiculous notion, since purpose can only be derived from "meaning") without any consideration whatsoever to their grave offense to the observer's aesthetics.<br /><br />They are desperate, you see? Desperate to find the "meaning" that conforming to the author's <em>IDEAL</em> can only provide. (They just never seem to <em>realize</em> it). Otherwise they would behave "properly", rather than in the intransigent manner that they do.<br /><br />What condescending dreck!<br /><br />Perhaps what I'm reacting to is a bit more than what these two examples let on, but I've seen a lot of aspects of this before. From eco-nazis to luddites to apocalyptic prophets of doom, to utopians, this same theme appears again and again. Look at most modern movies and their rank condescention towards the "common man". (Take the Matrix, for example.)<br /><br />(PS, that's not to say I don't have my moments of depression/pessimism/misanthropy. And it's not to say I think people are perfect or that you can assume their natural goodness. Far from it. It's for things like this that you have to watch your back when dealing with human nature.)<br /><br />The "sheeple" must be herded to greener pastures, otherwise they'll just stand there, doing whatever pleases them, and we can't have <em>that</em>, can we? It's often taken for granted that they will be herded by "evil" manipulators if they aren't herded by the "enlightened", "good" manipulators, that they have no volition or agency of their own, that their autonomous goals and desires aren't sufficient direction for their lives ("meaningless", "purposeless", "hopeless", "graceless"), or are irrelevant to the <em>Real Important Things</em>.<br /><br />All I can say is that, when you see this pattern manifesting, reach for your philosophical/political/moral wallet, you're being had.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-1160797016345972632006-10-13T20:35:00.000-07:002006-10-13T20:36:56.426-07:00Biofuels Revisited IIAh. Here's the relevant quote from Den Beste. <a href="http://denbeste.nu/cd_log_entries/2002/09/Morepracticalproblems.shtml">http://denbeste.nu/cd_log_entries/2002/09/Morepracticalproblems.shtml</a><br /><br /><blockquote>Biomass: I'm a bit embarrassed that I forgot this one to begin with. Biomass is, at its core, an extremely roundabout form of solar power. The idea is to use farmland to grow greenery, and then to burn the greenery to generate energy, but depending on who is making the proposal the details can vary wildly. Ethanol as a fuel is one example of this, but it is exceedingly inefficient because it is based on corn and only utilizes the grain, and wastes most of the energy in that and uses none of the energy in the rest of the plant.<br />A more efficient form of biomass is methanol, which can be created from the entire plant. The most efficient form is to burn the entire plant in a big power facility, for instance as a substitute for coal in electrical generation. There are some engineering issues involved, such as the fact that the biomass has to be dried or somehow have its water content reduced substantially, but that's a detail of the process.<br />It's an attractive idea, but I'm not sure the numbers make sense. I'm not sure I believe it's possible to actually supply a significant portion of our current energy use this way. You're only talking about actually harvesting greenery from the fields once or at most twice per year, and you're only going to get a few tons of dried fuel per acre each time you harvest. The US uses <a href="http://www.eia.doe.gov/cneaf/electricity/epm/epmt15p1.html">about 60 million short tons</a> (about 55 million metric tonnes) of coal per month, or about 650 million metric tonnes per year.<br />According to <a href="http://bioenergy.ornl.gov/papers/misc/energy_conv.html">this page</a> at Oak Ridge National Laboratory, anthracite and bituminous coal (which make up most of the coal we use) contain 27-30 gigajoules per metric tonne. Agricultural residues are 10-17 gigajoules per metric tonne (as a function of water content). As an approximation, that means about 2 tonnes of biomass would be needed to replace each tonne of anthracite. Are we actually capable of producing, collecting and transporting 1.3 billion tonnes of dried biomass per year? The US <a href="http://www.odci.gov/cia/publications/factbook/geos/us.html#Geo">currently has</a> about 200,000 square kilometers of irrigated land; can we generate seven thousand tons of biomass per square kilometer? Or even a tenth of that? Not easily, if it's possible at all.<br />One of the reasons we can produce that much coal is that it's concentrated; a given coal mine can produce millions of tonnes of coal with a relatively small amount of machinery. But biomass would be extremely spread out, and you'd need an impressive infrastructure investment for all the trucks to collect it and bring it to rail yards for transport to the power plants. And a non-obvious part of the problem is that right now our agricultural practices are using that same biomass, partly to stop soil erosion and partly to reduce fertilizer usage. (Also, a lot of it is used as animal feed.)</blockquote>qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com4tag:blogger.com,1999:blog-18967251.post-1160793673732063182006-10-13T19:38:00.000-07:002006-10-13T20:21:39.963-07:00Biofuels Revisited“Fletcher continues leadership on energy independence”<br />“USDA and DOE Fund Biomass Research Projects”<br />“$17.5 million for biofuels”<br />“Harvesting Sunshine for Biofuels”<br />“Biodiesel proves its worth with bus fleet (KRTB)”<br /><br />Some articles from around the internet. Bio-diesel is supposed to save us from fossil fuels. Bio-diesel will grow our way to sustainable energy. It’s the new clean green “way-of-the-future”. The people who aren’t onboard are “oil-lackeys” or “not aware” of fossil fuel’s limitations. They are standing in the way of our bright future. They are the reasons why we’re still dependent on foreign oil. They’re the reason why investors haven’t flocked to the farms. Yeah. Them. Oil lackeys. Bio-diesel is supposed to power our civilization in an eco-friendly way. Will it?<br /><br />I’ve always been skeptical. Actually, I’ve been derisive. The world burns 50 million barrels of oil per day. The US burns 20 million of those barrels. A barrel of crude oil weighs136kg, so annually we (US) go through about 1 Gtonne of oil per year. 1E12 kg/year. That’s the finish line. If you want to replace the energy we get from fossil fuels, you have to play on that degree of scale. As I’ve pointed out in previous posts that’s a no if’s ands or buts condition. We either generate that level of energy, or we all get a lot poorer and possibly subservient to those nations that manage to hold onto the oil. Civilization is not magically going to morph into some radically “efficient” form where people don’t need to eat, drink clean water, run factories, or ship goods. Can we get here from there growing corn?<br /><br />Subjectively, when I think of the fields behind my house, the breadbasket of the world, I can’t imagine that something harvested only once a year could possibly add up to that kind of mass. Could a field even fuel the tractor that harvests it? It doesn’t look like it to me.<br /><br />But let’s run the numbers. According to http://www.ag.ndsu.edu/pubs/plantsci/rowcrops/a834w.htm, North Dakota gets about 121 bushels of corn per acre.<br /><br />For soybeans, it’s around 40 bushels/acre. That’s industrialized, fertilized, mechanically planted and harvested soybeans. The “organic” (as if industrial agriculture is inorganic!) counterparts to soybeans rate around 16 bushels/acre. http://www.energybulletin.net/1469.html. And that’s from an approving site!<br /><br />Now, a bushel is an amount by volume measurement. A bushel of soybeans is around 60 lbs. That translates into 1.1 tonnes soybeans/acre. http://www.smallgrains.org/springwh/June03/weights/weights.htm Corn is about 56 lbs/bushel, or 3.04 tonnes/acre. Of course, that’s tonnes of actual corn. The North Dakota site gives around 16 tonnes of silage, and I assume that a fermenting reactor is not particular about which bit it eats.<br /><br />But you have to alternate corn and soybeans each year, otherwise you wear out your soil. You can’t go overfarming your land without crop rotation, unless you want to set off another dust bowl and ruin our ability to feed the world. So, assuming that you can just go corn/soybean/corn/soybean ad infinitum without consequence, you’d have an average of 8.5 tonnes/acre.<br /><br />If a tonne of produce could magically be transformed into a tonne of crude oil, then we’d need to farm 117 million acres constantly.<br /><br />*Note 1 hectare is not, as I have previously assumed, 100 acres. It is actually 2.47 acres. Big difference there. Nice to know when slinging agricultural lingo. :-P<br /><br />http://www.nationmaster.com says the following about our agricultural statistics:<br />We have 179,000,000 hectares of permanent arable cropland. We currently grow corn on 28,710,000 of these hectares. Soybeans on a similar area (expectedly). And of course, we’re well to the top of both of these charts, worldwide.<br /><br />So basically, we would need to devote land on the order of 27% of our arable land to bio-diesel production to make this work, <i>assuming 100% efficiency in food to fuel conversion!!!</i> We’d need to double the portion of our country devoted to corn and soybean production! And, as you all know, assuming 100% efficiency is a good way to be completely divorced from reality.<br /><br />(Side note – America’s farmland is actually doing far better in the analysis at this point than I initially expected. It just goes to show that you always have to run the numbers when talking about this degree of scale. Humans do not instinctively think in terms of quantities on this degree of scale. We can’t extrapolate from things that we’re familiar with, on our personal visual scale, onto levels of national production, without resorting to a lot of math.)<br /><br />Next to get an idea of the efficiencies involved, I’ll reference this article that caught my eye – “The Path Forward for Biofuels and Biomaterials”, Science Magazine, 27 Jan 2006. This article talks about harvesting wood for bio-materials. They are looking at something like 10-20 tonnes/hectare for woody crops, about on par with corn. (Though I imagine, far more involved and energy intensive to harvest). I <i>hope</i> they are including a suitable crop-rotation time for the forests to grow back, or we’ll denude our continent for a decade or so of fuel.<br /><br />They claim that a process involving super-critical steam can break up 57-77% of their bio-mass in their hypothetical bio-refinery into condensable gasses, which can further be processed into syngas (% not given), which can finally be processed into Biofuels.<br /><br />I think the Fischer-Tropsch process is commonly mentioned as a last-step in the creation of biofuels. Fischer-Tropsch can also process coal and other materials into fuel. For this DOE paper (http://www.fischer-tropsch.org/DOE/DOE_reports/NREL/TP-431-8143/TP-431-8143-1_sec1.pdf) it seems as if the maximum theoretical stochiometric efficiency of coversion is around 39.3%.<br /><br />Stochiometric efficiency isn’t by mass efficiency. It looks like they’re measuring mols hydrogen per mol biomass. CH1.47O0.67. Looks like it would relate to a hydrocarbon CnH2n with something like a 40% or 30% by mass ratio.<br /><br />So the overall process is looking like it’s around 25 – 30% efficient by mass. For brevity (and due to time constraints), I won’t consider harvesting, transporting, or the energy costs of refinement. We will need around 400 million acres of farmland to replace our gasoline consumption. We would need to be using something like 90% of those 179 million arable hectares for biodiesel production.<br /><br />I don’t think we’ll be able to replace gasoline with bio-diesel. I’ll admit that I didn’t imagine it would even end up in the neighborhood, but it seems our nations maximum possible agricultural production is at least in the neighborhood with what it would take to produce sufficient quantities of biofuel to free us from fossil fuels.<br /><br />Still, it doesn’t need to be pointed out that we don’t need to nuke our soil with incessant corn production. Nor can we cease our agriculture for our other purposes. We need food. We need corn syrup for almost every industrial process imaginable relating to organic substances. The rest of the world needs our food too. We can’t be giving 90% of that up to get rid of oil.<br /><br />You might protest that we’ll only need some fraction of our oil replaced by biofuels. 10-20% replacement is a good start. But the problem is, that's where it will stop too. What happened to “energy of the future?”. So we’ll be needing 80-90% of that oil after all? The goalposts have moved then. This won't be making us "energy independent" by any stretch of the imagination. And we’ll have to give up 10-25% of our farmland to achieve this? (And, assuming the economics of the situation don’t change, we’ll have to be subsidizing it at that!) Doesn’t sound like much of a deal to me. To pretend that it will replace oil feels too much like an agricultural scam.<br /><br />If you want to <i>replace</i> oil, I mean actually replace the energy behind it, you’ll have to turn to a different source. But at least, after examining the concept, I won’t laugh as hard as I was laughing. At least it isn't windmills.<br /><br />Steven Den Beste at USS Clueless blog (now, unfortunatel, inactive) has written several posts on alternative energy, mostly him raising similar objections to the ones I have raised, but with far more eloquence. <a href="http://denbeste.nu/cd_log_entries/2004/07/Justdoit.shtml">http://denbeste.nu/cd_log_entries/2004/07/Justdoit.shtml</a>. Somewhere in one of his three articles I thought I saw something on bio-diesel. Not sure though. And, though he thinks large-scale nuclear power production is an insurmountable marketing obstacle in the short term, I believe, as stated in my previous posts on energy, that the prospect of going back to the 17th century in the long term (100 years or so) is a highly persuasive marketing force.qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1tag:blogger.com,1999:blog-18967251.post-1159068526786266992006-09-23T19:41:00.000-07:002006-09-23T20:32:08.120-07:00Verne's Cannon Part II've been thinking that I've been a bit too much of a wet blanket lately on various subjects. I've tried to define things that I've felt were unfeasable, or unworkable, or didn't make any sense. Esp with my recent posts on energy (since I feel both that many highly touted alternatives simply will not scale, as well as that it's important to provide this energy somehow).<br /><br />But anyway, enough with what can't be done. Now I'm going to get downright whimsical.<br /><br />I've read threads on the space elevator recently. If we ever manage to get a material that has a high enough tensile strength versus density, we may yet be able to build the thing. However, nanotubes are still problematic, seeing as how they slide against one another. The macroscopic material may not end up with the strength of the individual fibers. (There I go again)<br /><br />So, I was thinking about other non-rocket methods of launching into LEO. One of the ones that has intrigued me for a while is a launch catapult.<br /><br />The launch catapult idea has been looked at by NASA as part of it’s 90’s X-plane efforts. In their formulation, the catapult will accelerate a rocket up to a few hundred miles per hour so that it can start a scramjet. However, it’s not intended to provide any meaningful contribution towards the total deltav required to get into orbit. The envisioned space-plane will still have to provide almost all of it’s own dv, which means it will still have to carry substantial amounts of fuel (and be aerodynamic besides, seeing as how it has to operate in the atmosphere for extended periods of time to get any advantage from it’s scramjets).<br /><br />However, I was interested in a mostly non-rocket launch method. What if we could get almost all of the dv needed to make orbit from the catapult? Maybe a circularization burn once the spacecraft clears the atmosphere, but have the spacecraft fire off the catapult at 8000m/sec or so, blast through the atmosphere, and off into orbit?<br /><br />This would basically be a re-creation of Jules Verne’s cannon. The system I envision is more like a 1000km long mag-lev acceleration track. (1000 km comes from the requirement to achieve this exit velocity while limiting the acceleration of the spacecraft to <5 g-forces. Shorter tracks can be made for unmanned rockets). I concatenated a lot of my older simulation code together into a simulation of a spacecraft ascending through the atmosphere, using Earth’s standard atmosphere model, under such conditions. In the simulation, I had the track firing the spacecraft off at a 0.5 degree angle with the ground. Assuming a light drag coefficient (around 0.05), my 200 ton simulated vehicle made it’s way to 25km altitude in less than 40 seconds (basically in a straight line). This is where my standard atmosphere model quits, so I assumed zero atmosphere afterwards, though this isn’t really the case. (a point of refinement for later models) Even though the drag forces are huge, they apply only for a very limited time. Dynamic pressure can become problematic.<br /><br />At this velocity, dynamic pressure is around 400 atmospheres (what a submarine would be experiencing at a 4km depth.) You might think this would sink the whole project. 400 atmospheres is a bit much to withstand for an aerospace vehicle. Furthermore, you’ll also have supersonic stagnation, and supersonic temperature for the few seconds you’re within the lower atmosphere. A normal plane or rocket would be crushed like a can.<br /><br />However, the mass limits for the launched vehicle aren’t determined by any normal aerospace consideration, but rather by the capabilities of the launching system. If you’ve already invested enough to build some 1000km long launch track, you’re probably going to want to beef it up as much as possible. Furthermore, a more massive vehicle is an advantage, since it helps the vehicle punch through the atmosphere. So why not build it like a submarine? Better yet, encapsulate the rocket in a steel pressure-vessel hull designed to blow off after the vehicle has exited the atmosphere. (freeing the payload to circularize into a stable orbit, and jettisoning the shield mass). The shell can ablate in blazing glory upon ascent and bomb out in the ocean. While you might think this is a waste of good steel, steel is cheap and plentiful. Remember, material costs are a minor fraction of the cost of a vehicle, and machining steel is absurdly cheap and well understood compared to most high-performance aerospace processes. We could easily mass produce all the ascent shells we would ever need as part of a major space effort.<br /><br />This whole approach is surprisingly workable, assuming you’re willing to build such a piece of infrastructure. Obviously this won’t be cheap or easy. It would have to be built across several states, (or, while I’m in this whimsical frame of mind, out in the ocean, between several platforms). It would only be justified if we really wanted to put mass into space on a daily basis, as part of a colonization effort or something. Other negative side effects include a car overturning mach 25 sonic boom at the exit. Still, this could be made to work (to my knowledge) with current material technology, and a boatload of powerful track magnets. If the space elevator doesn’t work out, this could end up being another railroad into space. <a href="http://photos1.blogger.com/blogger/5111/1864/1600/VCannon1f1.0.jpg"><img style="FLOAT: left; MARGIN: 0px 10px 10px 0px; CURSOR: hand" alt="" src="http://photos1.blogger.com/blogger/5111/1864/320/VCannon1f1.0.jpg" border="0" /></a><br /><br /><br /><a href="http://photos1.blogger.com/blogger/5111/1864/1600/VCannon1f1.jpg"></a><a href="http://photos1.blogger.com/blogger/5111/1864/1600/VCannon1f1.jpg"></a>qwerty182764http://www.blogger.com/profile/08597830467001613248noreply@blogger.com1