fred2014

You're right swansont - sorry - I should have thought to post a link. (thanks strange - I didn't have a link - I just read the brief news report at the time) Given the size of modern tech (I have some microchip PIC microcontrolers here about the size of a text full stop with features I find amazing) and low power use of same - I can see why this is considered a "potentially do-able" project. I'm willing to bet right now the final design goes to 5 gramms and the lazer L5 based, but still - amazing and potentially useful. The fact there are so many challenges - all interesting and potentially solvable makes the whole venture compelling. The probes we use "locally" now, have enough space to carry the required instrumentation. With the payload size so low my guess is you need to be able to provide survival tech. that takes up most resources. Then you need to do something when you get there and then send some info back. Thats a lot of function in 1 gram. Lets say you could take a photo from a few killometers out - without knowing the scale you have no way of knowing if it is a photo of a city - a cloud formation - or a grain of wheat. You need more information than the photo itself to work that out - and that means more instrumentation no matter how simple. My design would be to send 5 units out at the same time. (Good point fuzzwood) That would take negligable extra resources and provide scope for all manner of things.

I'm just curious about the project to send a 1 gram solar sail accelerated to a significant percentage of light speed in order to "image" a planet? The project reminds me of a scene in the UK TV series "UFO" where they sent a camera out and were amazed at the results ... until that is they realised they had no measure of perspective or distance or size. What they were looking at could have been anything. Is this 1 gram spacecraft going to have this issue or has that been worked out somehow? I'm also curious about what material could withstand the space dust and other particles out there at those velocities. Is this project really useful or is it a gimmick? What sort of data do we expect to get. (No doubt there would be some we didn't expect - that's the real fun part I guess)

24 members of a math department being sacked seems rather a lot to me? are these all actually teachers or are we talking cleaning staff? How many teachers/lecturers does the department have and how many students? I find it interesting the OP gives a location in poland.

OK - I had assumed that (given the fuss about it) there was some important information content. Are there any actual figures of what the variation is? Or indeed what the cause is - is it just aftermath of the big bang or dust cloud influence or whatever? (The problem with us casually interested bystanders is we never get the whole story - usually just the inept waffle on BBC teletext!)

swansnt - to me a small image with big pixels is a low res image (perhaps my computing background leading me astray) Presumably there are higher res images I havn't seen and that makes a difference. It just looks very turbulent to me. I don't mean to diminish the acheivment in any way - its just my impression. I was watching the BBC documentary on cosmology again just last night (I'm fascinated by the idea of colliding universes leaving circles on the map! mostly because it works perfectly with my own personal theory of how it all works out there - which is a bit different from anyone else I know of) It did occur watching that program that much of the leading edge thinking can still get stuck on the size issue ... for instance the universe shape being measured by the triangle of lasers - acknowledged as a great breakthrough demonstarting the universe is flat - but what if the size is really beyond current numerical immagination and those lasers are still curved a little but far beyond our ability to detect it - or perhaps lasers at any length just cannot do the job? proof of resolution and precision must be very hard especially as was said - the map is just the "visible" universe - what if it's much much older than we can measure or guess - and 13billion years old doesn't even equate closely to the true age? Then we can only see so far and guess - but maybe that makes a "flat universe" being capable of not being flat after all. (For anyone who didn't see the program the term "visible" is used in the scientific not specifically optical sense) As I said - not my field - but I've been listening to descriptions for many years now and am detecting what appear from the outside to be anomalous information. And to paraphrase one lady in the program "that's the fun part"

edEarl - I'd like to be wrong and for this to be a great advance. But I just can't see it. As for "cloud" computing - if I had my way it would be a criminal offence for any business to go anywhere near it.

Thanks john - I was very much afraid of that. klaynos - yes I've looked into most everything I can find online. Most of it is directly related to plasma technology (for pretty obvious reasons) but the tech isn't something that anyone not directly involved can penetrate too easily - at least I can't. If anyone knows anything at anytime or can help please feel free to jump in and let me know. Thanks.

From the lack of response I expect I've put this in the wrong place. Can anyone suggest another forum or source that may be able to help with this? TIA

This field is just a curiosity to me but to a "lay" perspective it looks to me as if the notion that variations are "minor" is at odds with the images published. Wouldnt the "low resolution" images of such a vast area simply appear as uniform as a childs balloon? I certainly wouldn't even remotely (again - as a "lay" person here) consider these images to be at all uniform.

I rather suspect this one is pie in the sky. The issues surrounding pipelining and parrallel programming make such a device highly innefficient - less so that a single core I would suspect. the notion of "more is better" is a comfy academic fantasy here I think. Not to mention finite access to system resources.

Does anyone know of software (or ideally) maybe a spreadsheet that would allow me to model the generation of electricity in a simple rule of thumb manner for MHD systems? Ideally I'd like to have some rough calculations I can just swap - say the main fluid from a plasma to mercury and see the difference or mercury to salt water etc? also be able to change other factors. Whilst I have a number of PDF files here explaining all the factors I don't have the math background to understand all the elements in detail. What I'm looking for is a means of demonstrating the simple generation of current by fluid flow through a tube and how that varies dependent upon the fluid - the volume of flow - perhaps the length of flow and coils designs etc. anything relevant but simple enough for intelligent demonstration of rough power calculation purposes. thanks

OK let's try it this way: Does anyone have a graph showing the average global accumulation of CO2 against altitude. One 2 axis graph (altitude and %concentration) - no names of height - nothing else. Also does anone have a map showing a plan view of the globe with CO2 density clearly indicated over identifiable locations. Nothing else. No opinions. Just one graph and one map both from identifiable and generally considered reliable sources. If either doesn't exist please just say so and I'll stop asking. And please refrain from polluting the thread.

OK I seem to have poked a hornets nest here. Sorry - I just thought it was a simple question. The responses have me somewhat confused. I had assumed that this was a cut and dried issue someone could just give a simple answer to - and that coloured map makes no sense to me at all. I'm more confused now than when I asked!

hmm... Ok thanks. The original question seems to be drawing blanks right now. If anyone has anything to suggest for my original post I'll pop back from time to time. Thanks to all posters for the input.

Sorry if this is a stupid question but it's outside my field and just something I was curious about... As we burn fossil fuel we release Co2 "into the atmosphere" So my question is - does this Co2 collect in a band around the planet at a particular altitude or is it dispersed at all levels throughout the atmosphere?

If I may add my tuppence: It seems to me that hybrid cars don't help they actively damage what they claim to provide. You don't build 1 engine you build 2. 2 sets of components sourced, mined, transported and manufactured on 2 production lines to install in an extra complex car requiring increased electronics, parts and control all of which needs manufacturing with additional maintenance and spares all round. If I had my way they would be outlawed. My belief is that these cars only exist because the oil industry is trying to delay any change over to full electric for as long as possible. Full electric means not just less petrol/diesel consumption - it also means less maintenance and less need for fuel pumps. Fewer spares, less complex maintenance, less lubrication - in a phrase - an entire industry devastated from top to bottom and the share price of oil companies falling through the floor. The only thing stopping that is insufficient electrical production by other means. We just couldn't power all our transport by current or projected generation. Fracking is a totally desperate and seriously dangerous red herring. Nuclear fusion will not be running anytime in the next 50 years and in practice is not much "cleaner" than fission anyway. Just a little safer to run. At least it will be if anyone can be bother to build and operate them safely which - given the history of fission even to this very day - seems unlikely. Hybrid cars seem like the worst possible thing to buy into to me.

thanks again... Indeed magnetism is complex - by any standards. The fact that people are using FEA to calculate fields tells me enough. Yes you're right my experience is more electronic than magnetic (I started in military radar many years ago) - I have basic transmission theory knowledge but it's unused - and no design experience of magnetic fields at all. I think I'm understanding maxwell better now - but hopefully I can avoid getting too involved in the math and rely on experiment to start with then refine things later. I'm looking at various modelling packages - the one at edinburgh for ground penetrating radar looks like it may offer me some insight into principles of interest. This is really a seat of the pants project - I'm pushing everything to see what I can get rather than designing for specific values. The function has been tested with very large impractical equipment - the task now is to make it practical. That may mean throwing out any pre-concieved notions if I can find genuine ways around them. (Invention is kind of like that...) Fortunately I don't believe in death rays or perpetual motion - although I do have knowledge of a long range accoustic "gun"! (look into non-lethal weaponry) Copper losses are obviously an interest - especially with battery power - (a 7T field is impressive) - one thing I do have down to look into is a graph of cooling - at what temp do losses start to reduce and whether copper is the best medium - gold maybe? (as mentioned above - cost isn't an issue). It's been brought to my attention that significant cooling may be a possibility in the volumes I'm working with. I take your point about ferro cores. Coil construction - I'm not so sure. I have a couple of ideas - maybe nonesense but maybe not. There may also be some info at nasa I can use - I seem to remember they ran one of their "competitions" to design a small portable mri machine - there may be some papers worth reading on that - although probably fixed magnets again for the machine but someone has probably tried to be clever - they often do in those competitions. Out of the box is where I live right now and sometimes crazy can be usefull to spark things off. Are you able to discuss your 7T project at all?

Thank you Enthalpy. Well spotted. I've been looking into the possibility of sequenced capacitive discharge. (Using a microcontroller to sequence things) I'm working on a design to experiment with this now. If I can keep the output regulated sufficiently this may be one way to go. I'm also looking into more exotic materials and complex coil construction. If anyone knows of any good design software that can help with this sort of work I'd appreciate a heads up.

Thank you all for the responses.

I think I've made the parameters clear enough. Trying to change them doesn't help me I'm afraid.

Thank you both for the quick replies. As mentioned a fixed magnet is not possible. I understand the benefits of supercooling but in such a device that's a bit impractical! Operation is only required in bursts of 1-2 seconds at a time - short high powered magnetic field is needed. The field need not extend from the device more than about 1cm Are there any tricks that can be used to : a) Reduce the size and weight b) Increase the current flow - or otherwise increasing field strength I was thinking maybe special design of coil or multiple coils and is there anything better than iron as a core. (I should also say cost is not a big factor for the design) Thanks again

Hi I have a concept for a device to assist in a manufacturing process that would require a hand held electro-magnetic device. (Not fixed magnet) (I would prefer not to discuss the actual process for confidentiality reasons) The device needs to be hand held - not a robot arm. The device needs to be comfortable to hold and move about for short periods of time (I'm thinking weighing less than 1lb in total including power source) (Must be battery powered) I'm looking to develop as high a field strength as possible as the higher the better - also if it can be focussed to some degree that would help. Whilst I have electronics skills I have no practical experience of electromagnet construction or materials beyond common electrical knowledge and my knowledge of magnetic fields is similarly limited. Does anyone have any comments on a good way to go about this (presumably there is science beyond simple windings and cores somewhere?) A prototype device has demonstrated this is worth my following up but I need much higher field strength and to be able to make it hand held to be really useful. Any comments or ideas on any area of this are welcome at this stage. Thanks