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Andymarrison

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Everything posted by Andymarrison

  1. Maxwell (probably quite sadly, got goosebumps the first time I had Maxwell's equations explained to me in a lecture - just beautiful); Dirac; Einstein; Feynman; Gauss; Riemann; Hardy; Ramanujan; Chandrasekhar; Sagan (completely inspirational to me as a young teenager). If I had to order them, I'd put Maxwell first, as the first to produce a proper "unified" theory of two forces previously considered separate. Or maybe Einstein...
  2. Fully agree on the thermodynamics - as far as I could make out it was just a randomly selected set of equations and laws to be assembled in any order the lecturer saw fit on the day. Still, it's quite impressive that they figured out how to make an engine out of a carrot, I agree . It's a wonder how I passed, really... Whereabouts in Oxfordshire are you, x6gas? Feel free to a. not answer that question; or b. PM me, if you don't want to broadcast your location to the universe! Nice set-up, by the way!
  3. Hi Stevie - surely you've got that the wrong way round?! Welcome to SGL and I hope the wonderful Welsh skies clear for you soon!
  4. That's great thanks guys! Lots to go on - I'll certainly be buying one or maybe even all of these titles. I should say I've no ambition to build anything (because [a] I'm a perfectionist, I I'd never finish it; and my 4 year old and 2 year old would in any case have their sticky mitts all over it within seconds!), but I like the idea of the books aimed primarily at practical projects because I think they probably give more of a flavour of the real limitations of an optical system and their causes. If your course was anything like mine, Capricorn, it fell between the two stools of a mathematically rigorous approach on the one hand and a course firmly tied to practical imaging problems on the other - it therefore failed to capture anyone's imagination. An introductory undergrad optics course based around some practical problems in astronomical imaging would have generated much more interest, I think. Incidentally, which University did you study at?
  5. Hi Brent - that's a BIG scope you've got there! Enjoy! Welcome to SGL!
  6. Yep - really looking forward to the Peak Star Party in October in particular. Spending a good proportion of these light, cloudy evenings looking at tents on the internet, in anticipation...
  7. If I'm remembering right here then the important thing is that the size of the reflecting dish (the equivalent of a mirror for visible light) is large enough in relation to the wavelength that is being observed (in this case radio waves, which encompass a very wide range of wavelengths, but let's say around a metre for the sake of this discussion) that diffraction effects don't dominate the image. So in other words the diameter of the dish needs to be many times the wavelength of the radio signal. Similarly, it's not necessary to have a nice smooth dish because the long wavelength radio waves don't "notice" imperfections in the surface as long as these are smaller than their wavelength - so some conducting wire mesh with holes of a few cm, in this case, wouldn't matter.
  8. I had a look on Amazon and this one looked the closest to what I might be looking for http://www.amazon.co.uk/Astronomical-Optics-Daniel-J-Schroeder/dp/0126298106/ref=tmm_hrd_title_0?ie=UTF8&qid=1340522405&sr=8-155. Which textbooks from Uni do you have, Capricorn? My degree was in Theoretical Physics, so I'm happy with a fair degree of mathematical and physics content, though ironically I always hated optics - twenty-plus years later I'm wishing I'd paid more attention!
  9. Hi everyone Can anyone recommend a good book on optics for astronomy? I'm comfortable with all the tricky maths etc but would get the most out of a book that combines this with some sensible, practical observations about the characteristics and limitations of different systems. Thanks! Andy
  10. No, no, we can't leave it there! It's just getting interesting!! When matter falls into a black hole it isn't lost, as noted above. What is lost is the information that the matter carried with it - or more precisely all of its characteristics apart from mass, electric charge and angular momentum, which are all "taken up" as properties of the black hole. This is known, rather brilliantly, as the "black holes have no hair" theorem. Going back to mass - if you're a long way from a black hole you'd orbit it quite happily in the same way as if it was just a star of the same mass. What distinguishes a black hole is how strongly space-time is warped (which is what gravity is) close-in.
  11. These are all just complete genius! Great thread!
  12. ...maybe, but they did give us some very nice Dave Gilmour guitar solos - check out those bends!
  13. Andymarrison

    Nothing in Sight

    ...I can only imagine that you're talking about clouds. Welcome to SGL Graham!
  14. Andymarrison

    Hi from Kent

    Hi Mark - lovely telescope - I have its little sister and am very jealous of your extra 3" of aperture! Welcome to SGL!
  15. Hi Dave - lovely scopes and equally lovely guitars! Welcome to SGL!
  16. Hello and welcome to SGL - nice website and very nice images!
  17. Hi Matthew - I think I've taken a similar path in life - my degree was in astrophysics/theoretical physics, but after a few years as a professional physicist, I decided that, as a career, it just wasn't for me. I still love all things related to astronomy, cosmology and particle physics, though, and it's great to return to the subject as an amateur and to have the freedom to enjoy it as a hobby rather than pursue it as a job. Hope you enjoy your newly rediscovered pastime, and welcome to SGL!
  18. Ciao Fabio! Come sta?! Spero che sia un tempo migliore in Italia che in Inghilterra, e che si vedano bene le stelle. I genitori di mia moglie sono Italiani, e provo a imparare questa bellissima lingua anch'io. Ciao! Andy
  19. you're dead right, Stu - even in late May, at 11pm before things had got properly dark, the sky was a pretty amazing sight. I'd definitely head up there again, but it's as well to let the staff at the castle know beforehand, and probably Wessex Astro as well, just so they know that the guy/girl bathed in a pool of red light at the dead of night isn't up to no good!
  20. Not sure about a campsite, but a lovely dark sky location on the south coast is Durlston Country Park which is about one mile outside Swanage right on the cliff tops. This is also where Wessex Astronomical Society have their observatory, and I set up there while we were on holiday recently and enjoyed a lovely night's observing with the secretary of the society, who was very kind and hospitable. Their website is here: http://www.wessex-astro.org.uk/. Swanage is very close to the campsite mentioned earlier in this thread by BigMakStutov, so that might be a good bet.
  21. I have a 24mm Hyperion and, generally, am pleased with the results in my f10 SCT. However I agree that a good eye position is not always easy to find and that's not helped, for me at least, by the fixed rubber eye cup. I got a new BST 15mm yesterday and have to say it's a lot more comfortable and "natural" to use, in large part due to the nice twist up adjustable eye cup.
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