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Making The Best of Light Polluted Skys

  1. Apr 16, 2009 #1
    I live in a very light polluted part of the country (NE) and I am unable to see any stars near the horizon but a lot of stars actual show up at around zenith, are there any ways for me to get good looks at things that are from 4-6.5 magnitude with only 20x80 binoculars? I am saving up for a telescope which i hope to buy in the next few months but will i even be able to see anything with such bad light pollution?
  2. jcsd
  3. Apr 16, 2009 #2


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    By "good looks at things from 4-6.5 magnitude" I assume you mean galaxies, nebulae, and the like (because stars are easily visible at these magnitudes through your binoculars). I regret to inform you that if your skies are as light polluted as you say, the most you will probably be able to see is the Orion Nebula, and probably the central part of the Andromeda Galaxy (This will look nothing like a galaxy. Fair warning).

    If you're only limited by binoculars, if you have a car it could be worth it to take a drive out to the country to get better looks at some astronomical objects. You can see the light pollution situation at:

    Which also gives a relatively accurate assessment of seeing, humidity, and other conditions.
    Try, as much as possible, to observe from a location where there are no local lights (shining in your eyes, or even near you). After 10-20 minutes in such conditions your eyes will start to see many more stars despite no change in the overall light pollution.
    Other things you might try viewing include open star clusters (particularly, start with the pleaides), and it doesn't hurt to try a globular cluster either (but don't expect much).

    There's not much you can do about the pollution with binocs except get to a locally dark site or travel out the the country.

    Also, do not expect markedly different results with a telescope from what you achieve with binoculars. In heavily light polluted skies, the amount of skyglow increases with the size of your lens, so the effect almost cancels out the increased light from the source. Basically, size doesn't matter much for faint of objects you can see. (This isn't strictly true but it's a good approximation which appears to hold true from my experiences) So, with a telescope expect to be able to see what you already can see with the binoculars, but with greater resolution (planets will appear much crisper, you may be able to see more detail in the Orion nebula), but again, don't hold out for markedly better images from a telescope.

    Sorry if this all sounds a little grim, but I have been the victim of horrible light pollution as well and am quite bitter about it!
  4. Apr 16, 2009 #3
    I have already viewed Pleiades which was not great because around this time of year Pleiades is only visible low in the sky so I was only able to see the 7 main stars in it. I would have tried to view the andromeda galaxy but I can’t find it around this time of year. How would Saturn appear through 20x80 binoculars? I would assume that Saturn would still be quit bright if I was looking for it around 1 AM since light pollution drops off a bit after mid night.
  5. Apr 16, 2009 #4


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    Your viewing of the planets won't really be diminished at all by light pollution, which is the good news. Saturn will appear as a small disk in your 20x80s, and you should be able to make out some of the rings if you have the binoculars steady, although the rings are seen nearly edge on right now. Probably you'll also be able to see a moon or two. Jupiter, when it's in the sky, will look nice too, and again, if you have steady binoculars you should be able to make out some detail in the cloud structure and the four gallilean moons.

    The good news is, these objects appear much more spectacular in a good (even decent) telescope, because you get to make use of the increased aperture to magnify. The bad news is that planets are about the most impressive thing you can view from a heavily light polluted sky.

    It might be a little late to catch M42, because if memory serves it sets not too long (few hours) after sundown, but it might be worth trying to glimpse.
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