Light pollution has always been a problem and it is the bane of modern observational astronomy. Its funny how we live in a "golden age" of affordable equipment, and yet we have to travel so far just to get to pristine dark skies for deep sky observation. Its kind of silly really as I remember growing up in the late 70's/ early 80's and the skies back at my parents place in Peninsula Malaysia was dark enough to nab some really interesting deep sky objects (DSO's), even though back then all I could afford was a 40mm f/20 Celestron Cometron refractor! These days the same skies appear pink with light pollution! Moving to Brisbane, Australia in 1997 for my undergrad studies and then moving there to live in 2001 showed me what good light management could do to improve the skies (the skies were actually black and not grey or pink!). Over the years, it also showed what development could do to "lighten" the skies up. The skies over Brisbane in 2010 and Brisbane way back in 2001, or even 1997, show distinct differences, even though they still appear black overhead. I estimate a magnitude loss of anywhere between 0.2 to 0.4! I now live in Los Angeles, one of the most populated cities in the world and even here the skies are better than back home in Malaysia or Singapore! But moving here from Brisbane also dramatically illustrated how even a loss of 0.4 magnitude (Brisbane's limiting magnitude in winter approaches 5.5, while here on the best of nights I can get 5.1 tops) can do to decrease the number of stars and DSO's visible to the unaided eye, or even detail at the eyepiece. So yes light pollution is a problem and unless we do something about it, soon we will not even be able to see past the brighter planets and the moon!
The immediate addressable problem though is how and what we can see from light drenched skies. Many people who live in large cities seem to think that all you can see are the brighter planets and the moon. That is not true if you are experienced and know what to do! DSO's are totally doable from such skies. I will give you a rundown on what you can do to track DSO's down from relatively bright locales:
- a nice transparent winter or coolish night (best after a front has passed) close to the new moon
- pick a spot that is shielded from ground lights at eye level
- setup on grass and not on concrete (concrete traps heat in the daytime and radiates at night when it cools down)
- use a monk hood (a black cloth that can drape over your head and eyepiece)
- experiment with different eyepieces to get the optimal magnification
- use a longer focal length scope
- use as much aperture as you can handle (the old myth that small refractors are better than large reflectors are pure baloney....bottom line is the larger the scope, the more you can see)
- flock your scope's tube with velvet or flat black paint to improve contrast
- use ultra high contrast or narrowband light pollution filters (make sure you use a hood with these as they can reflect stray light back into your eyes and reduce contrast)
- observe later at night (most establishments turn their parking lot lights off after a certain time, plus there are less cars on the roads at night)
- use a light shield (such as drapes over a frame)
- remember to allow your eyes to dark adapt for at least 30 minutes...start with brighter objects such as open star clusters, then proceed to the fainter fare
On a wider scale that's when it starts to get complicated. To really get involved in turning the light pollution situation around consider joining the "International Dark Sky Association". They provide education and resources to combat light pollution at an international level by promoting good and energy efficient lighting habits...
http://www.darksky.org/mc/page.do;jsessionid=9A6F57442A49F3938C2EE5CC3251E9A9.mc1?sitePageId=55060
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