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Gfamily

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About Gfamily

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    Star Forming

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    N Cheshire
  1. A factor to be taken into consideration is the 'optical depth' of the stellar atmosphere, which depends on the amount of ionisation that determines how far light can travel before being absorbed and re-radiated. So; it's the free electrons that will prevent light from the exterior having a free path to your eyes. As recall, the 'surface' of a star is the depth at which a photon has a 70% chance of directly making it out of the star. Below that, even without the local radiation, you wouldn't be able to see the 'outside' universe (similar to the way that even thin cloud blocks our view of the night sky).
  2. The Heritage 130p that has been recommended above is a very good scope. Compact when not in use, it's straightforward to use, and has very good optics for the price. The design came out of the work of an organisation called Astronomers Without Borders, that was looking to create a telescope that could be used to encourage interest in astronomy in developing countries. It's one that can be upgraded too - as it can easily be moved to a different mount later on.
  3. I'd be very pleased with that image! It's worth checking the position of the Jetstream, as that's going to make a significant difference to the quality of your sky. https://www.netweather.tv/charts-and-data/jetstream It wasn't particularly good last weekend (from https://www.metcheck.com/WEATHER/jetstream_archive.asp) , but was better last night
  4. A mobile phone running planetarium software such as Sky Safari can, in principle, be used as a sort of 'Push to' finder for telescopes - you'll need to get a suitable bracket to line it up with the scope get an accurate alignment of the phone with the sky Basic Stellarium mobile doesn't seem to do this, but Stellarium Mobile Plus (£7.49 on Android) or the free Sky Safari 6 will work for this. I'm sure there are others as well.
  5. I've tried looking at images online, but it's not clear how the scope connects to the mount. It looks as though there might be a short dovetail, and if that has a 1/4" threaded bolt hole, then you might be able to attach it to a tripod. I have a couple of Skywatcher Maksutov scopes with mounting holes on the dovetail, but you'd need to check what there is on your scope. If it doesn't, you could look for tube rings that would hold the scope and allow it to be tripod mounted.
  6. You can get sticky velcro pads that might work equally as well.
  7. Hmm, I'm trying to be helpful to the OP and to anyone else that has a similar problem. Saying "you want to be looking at something at least a mile away" is very misleading if taken at face value. Most people can find something 200 metres away from their gardens in the daytime, whereas only a minority could see something a mile away. It's not being pedantic to point this out.
  8. Yes, but it's very misleading to imply that unless you have a clear view of at least a mile then there's no point. If your focuser doesn't have 5mm of travel you have other problems
  9. I wouldn't go that far, if you can find a target that's 200 metres away, it'll only change the focus position by about 5mm (for a 100cm focal length Newtonian). Yes, it needs to be something outside your garden, but a distant tv aerial or streetlight should be usable.
  10. You wouldn't normally use a diagonal on a Newtonian , but it might be worth taking a photo of the focuser with the eyepiece in place.
  11. This was brought home to me when visiting Mount Palomar (as a tourist) several years ago. There's a small gallery of exhibits that has a view into the dome - and some small vents, through which you could feel a flow of very cool air seeping out of the dome. Their weather forecast predicts the air temperature expected for that evening, and the dome and scope is pre-cooled to match so as to reduce the thermals when the dome is opened.
  12. Just for clarification, insulating scopes is done to reduce thermal currents and improve the quality of the image. It's an alternative to having a longer 'cool down' time, which can be significant for Maksutov scopes. Insulating may have a minor effect on dewing, but only because it'll keep the corrector plate slightly warmer for longer, but the benefit will be minimal. A dew band will be far more effective.
  13. Arp's principal claim is that alignments between galaxies and AGNs are far higher than statistically likely, hence there is a physical cause for the correlation, and hence that red shift (for certain classes of astronomical objects) is not correlated to distance. At the time of his claims, we didn't have the data about the distribution of quasars that we have now. The main argument against isn't "red shift proves Arp wrong", it's "More data shows that Arp's principal claim isn't correct". Picking individual cases and saying "this looks like it's closer than that", or "these two things look like they are connected" is a weak basis for challenging the generally accepted cosmological model. Extraordinary claims require extraordinary evidence, and if the principal item of evidence (the statistics) has been discounted, then reverting to individual 'odd looking' cases is not really strong enough.
  14. Ummm, what makes you think there hasn't been examination of the ideas, or that they've been dismissed for little scientific reason?
  15. It's always worth spending some time learning the names of "landmark" stars: Merak and Dubhe, the two pointers in the Plough, Polaris - of course - not particularly bright, but the brightest in its area of the sky Mizar (second star from the end of the handle of the Plough) Arcturus - follow the curve of the handle and you'll reach Arcturus, In the Summer, the three stars of the summer Triangle: Deneb, Vega and Altair (lower down) In the Winter, the main stars of Orion (Betelgeuse and Rigel), The Winter hexagon - Arcturus, Capella, Castor, Procyon, Sirius and Rigel. If you can identify these as they appear in their different times and locations across the year, you will be well on your way to finding alignment without any stress, Aplogies to those hearing me say this for the umpteenth time, but a great help for finding the suggested stars is to get yourself a 12" Philips Planisphere - it shows the whole visible sky for your time and location in a single view, and has the brighter stars named. Yes, you can get something like this on an app, but I don't think there's anything as effective at showing how the night sky changes hour by hour and month by month, with constellations being visible firstly in the east, then moving west as the hours go by and as the months go by.
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