Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.



  • Content Count

  • Joined

  • Last visited

Community Reputation

36 Excellent

About DaveNicko

  • Rank

Profile Information

  • Location
    Leeds, UK
  1. Well done! I got the scope out for the first time in a while only to be scuppered by the awful Leeds light pollution. :-(
  2. I think some confusion arises with the cleanliness of mirrors due to the human mind trying to equate a telescope mirror to a (for example) bathroom mirror. When you look in a bathroom mirror you see an image of yourself. If you look at your left eye, the mirror is reflecting the particles of light in that region of the mirror alone - the rest of the mirror is redundant. If you were to place black card over the rest of the mirror (except your eye) you would still see the reflection of your eye at the same intensity as if the card weren't there. Conversely if you were to block the mirror with black card in the position that you can see your eye - you wouldn't be able to see your eye! Now consider a curved mirror in a telescope. Photons of light from a point in space (a star say) don't hit just one part of the mirror, they hit the entire mirror. That is to say that a photon of light emanating from a star hitting the left side of the mirror will be reflected towards one point of the image plane (which the eyepiece helps focus), and a photon of light emanating from the same star hitting the right side of the mirror is also reflected to exactly the same point of the image plane due to the different angle of incidence with which the photon hits the mirror. This is true for all photons of light hitting all points of the mirror from that same point source of light. Therefore lots of dust on the mirror will theoretically affect some of the light entering the mirror, but there are always lots more photons from other parts of the mirror making it to the eyepiece. This is a fairly complex subject which combined with my lack of understanding makes it difficult for me to explain, but I hope this does make at least some sense... Dave.
  3. I've been on Holiday for a week! Sad news. It might be worth going to a local astro society to see if they can help. It's strange that it works on some peoples 130p but not others... Maybe there is something simple we've all missed? Dave.
  4. Thanks! My future plans include: Mount, imaging scope, and CCD for what will likely be variable star observing rather than pretty pictures. Followed by (possibly at the same time) a diffraction grating. This won't be for a few years though - at first I plan on starting getting some visual variable star observing in. But at the moment I'm just enjoying my new scope (200mm dob)! Dave.
  5. Nice spectrum! Are you using a diffraction grating? (I say this as someone who knows very little about astro spectroscopy). I guess the spectrum is directly horizontally right of the SN in the image? At some point a long time in the future I would like to get into spectroscopy - but not for a while! Dave.
  6. Yes it is very difficult. Even though I could (just) see it directly, the brightness changes when you look at another star, and the star dims when you look directly at it! I just tried switching quickly between stars and SN to try and compare it. I only looked at the three stars in a line pointing to the SN, and then went inside to look at the chart - so both those points will introduce further error. It still looks to be increasing in brightness though - hopefully it will reach Mag 8 so it will be visible in Binos... Dave.
  7. I got 11.25-11.5 last night. There are some links to light curves/magnitude charts in this thread: http://stargazerslounge.com/topic/206148-m82-supernovae-light-curve/ It seems to still be steadily increasing in brightness at the moment... Dave.
  8. The second link seems to be broken now. But you can go to the following link: http://www.aavso.org/vsp/ And enter "sn 2014j" to get the chart. I had another look tonight and estimate mag 11.25-11.5, which is quite some variation! But to be fair it's the first time I've ever noted the magnitude of an object..
  9. Lots of gamma rays I imagine :-)
  10. No problem :-) I imagine you could read by it at night and see it during the day of were on a planet orbiting a neighbouring star. Much like the crab nebula in 1054 (although that was a core collapse Supernova, not a type 1a).
  11. *points of light - wish I could edit posts!
  12. Actually the size is a bit of an illusion. The supernova is actually a tiny spot of light - like all stars - and only seems big because of the airy disc which occurs due to diffraction of photons. The only things in the night sky which don't appear as points if light are the planets - they appear as discs. And also some of the larger closer stars (like Betelguese) I think have been resolved as discs photographically... Hope that makes sense, hopefully someone will correct me if I'm wrong... Dave.
  13. Thanks all for the comments! I managed to see the S/N too, so three firsts last night! This being the first time I have seen it I don't know. However I think the seeing had some say in it last night... Dave.
  14. OK. I know it's not a variable star, but the following is a link to the light curve of the recent supernova in M82: http://www.aavso.org/lcg/plot?auid=000-BLG-310&starname=PSN+J09554214%2B6940260&lastdays=20&start=2456678&stop=2456698&obscode=&obscode_symbol=2&obstotals=yes&calendar=calendar&forcetics=&grid=on&visual=on&r=on&fainterthan=on&bband=on&v=on&pointsize=1&width=800&height=450&mag1=&mag2=&mean=&vmean= Obviously there isn't much data yet, but it will be interesting to follow over the coming weeks. And a chart in case you want to generate some data yourself: http://www.aavso.org/tmp3/d8520.png I haven't even begun to record variable stars yet, and I am away next week so won't be able to do this. It would be interesting to see if anyone else out there is going to have a go though! Dave.
  15. Yes, got it! Just about to go to bed and I looked outside - gaps in the clouds. And there it was. Brilliant, three firsts tonight (along with GRS and Io transit on Jupiter) :-D
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.