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Jay-qu

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Jay-qu last won the day on June 8 2012

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About Jay-qu

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    Ancora Imparo
  • Birthday 01/27/1988

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Converted

  • Biography
    In the process of becoming an Astro-physicist
  • Location
    Australia
  • Interests
    astronomy, basketball, bodyboarding, skiing
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    student
  1. The sun is just too bright to image directly.. you need some good crossed polarizers or an ND5 filter. The internal reflections of your camera serve this purpose, reflecting only a small amount of the light and so the flares look better than the direct image. Also try some solar viewing with a pinhole, projecting the image onto a surface. Since there is no next time for us, you can just enjoy the images I took :D
  2. Just yesterday a new result was published showing that study to be incorrect. They made an incorrect assumption about how stars move within our galaxy, see here for the details: http://arxiv.org/abs/1205.4033 J
  3. As I'm sure everyone was aware, on Sunday part of the western coast of the united states got to experience an annular eclipse - which was also my first eclipse :) We drove a few hours north to extend 'annularity' to a full 2 minutes. Giving me just enough time to setup - and do a rough align (need to practice more day aligning :\ ). Fortunately I got lucky and the scope only required a nudge every 10 mins or so. With the eclipse finishing at Sunset, the diminishing light meant I had to extend the exposure from about 1/640 to 1/80 and double the ISO... Unfortunately this means the colours cha
  4. I don't think Elburg's point is relevant. The distance measurements are made with the GPS and transformed into the European Terrestrial Reference System (set in 2000 (it changes due to continental drift)), this is routine GPS work requiring special and general relativity. The timing measurements are checked with synchronised Caesium atomic clocks at each lab. I like your idea Qfwfq, but how do you resolve it with supernova neutrino observations?
  5. While this is a potentially exciting result, I am highly sceptical. Fitting the neutrino beam "profile", a mere 16,000 counts over the life of the experiment, to the proton beam is tricky to say the least. Before systematic effects are subtracted there is discrepancy of 1050ns, they account for -990ns, leaving the neutrinos 60ns faster than light over the ~720km. Have a look at figure 11/12 and ask yourself how much difference it makes to the fit if you shift the red line by just 50ns (one division/bin in fig 12) to the right. This would bring the result within error of c. And you don't have t
  6. An experiment to see if google can nest an image, like holding a mirror up to a mirror
  7. Welcome aboard :) do not be shy to ask anything, we will be gentle.
  8. This isn't a very complete poll.. we know the Standard Model does not explain everything, but it does do a tremendous job of describing physics within its domain of validity. The current results collected by the LHC have not done much more than the Tevatron has already, but by the end of the year the LHC will have charted some new territory. The 'Standard' Standard Model has a simple form of the Higgs, but it is likely that the Higgs mechanism will be effected by or be part of physics beyond the Standard Model. Unfortunately our current experiments don't give us much to go by, but hopefully
  9. Hello afsred, A quick google search turned up this resource which provided the answer of 436 kJ/mol I hope this helps, J
  10. At this point I would just like to note that I am part of the scientific community researching dark matter and that I agree with everything Craig is saying. In lieu of the reputation system we used to have, I commend you here instead: Craig, your patience matched with your intelligence and fluid prose make you a formidably lucid explainer of all things scientific. I don't know where this site would be without you :thumbs_up
  11. The veracity of their maths is one of the things the peer review process is supposed to check. I cannot vouch for whoever reviewed these papers as I am not an expert in GR, but I can say that something must be going wrong somewhere. GR also predicts DM through the observations of gravitational lensing, I dont think there is an easy way to reconcile these two observations. If we accept that GR is a consistent theory of gravity, then one of the observations must be wrong. Now considering the case of the bullet cluster, it makes it considerably less likely that lensing observations are wrong.
  12. I would take those papers listed with a grain of salt. Only one has been accepted in a peer-reviewed journal and even then it was a pretty low impact journal (IF = 1).
  13. These are good questions JMJones, I will do my best to give you some answers: 1. Quick answer, yes there is dark matter in our solar system, but not much. Since dark matter interacts mostly through gravitation (it is assumed to interact other ways too, albeit weakly) it acts like a pressure-less gas. The effect of this is that it does not 'clump' as much as normal matter. Data suggests the Milky Way galaxy may have ~90% of its mass in a huge dark matter halo that extends far beyond the visible reaches of the galaxy. At the point of our solar system in the galaxy the density of dark matter is
  14. The existence of dark matter is well established beyond just galactic rotation curves. See, for example, the Bullet cluster merger: http://apod.nasa.gov/apod/ap060824.html, which clearly shows that the majority of mass in this system is non-baryonic. There are theories that attempt to reconcile dark matter by modifying gravity, given the name MOND. All I have seen of these theories so far are in-elegant, adhoc solutions that cant cohesively provide a single hypothesis to cover all dark matter observations. If you are still unconvinced have a read of this: http://www.sdss.org/news/releases
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