Sunday, April 22, 2012

Urban Astronomy - Seeing the Skies in Light Polluted Areas



"Urban Astronomy - Seeing the Skies in Light Polluted Areas"," Its not just residents who feel this way, I've even talked expert astronomy authors who have told me that there was no reason to get a telescope larger than 3"" diameter for city use as the light pollution would make that extra aperture useless.
 In fact, there are a few tricks you can do that may actually give you a decent viewing experience:

Look Up!

Its a sad fact of life in the city: People rarely actually look up! And when they do, it is usually to admire some brightly lit building.
 Of course, make certain you are not looking up at a tall building or street light first!

Get Away from the City Center

The center area of any city is where its light are brightest and its building are tallest.
 I myself have been able to naked-eye view the Orion Nebula (with averted vision) from both the Ferry Docks in Manhattan, as well as in Northeast Philadelphia!

Get High!

The vast majority of light pollution in a city comes from its street lights.
 But the good news is that most of street lights' light is pointing down (and sadly, being reflected back up, but that's another story).
 Decks and roofs are not ideal for astronomy.
 In addition, not all roof decks have access that is easy to bring a telescope up to.


Pick Your Nights Wisely

If you want a chance to see more than just the Moon and Planets, you will need to be choosy about which nights you want to do city observing.
 The best nights for viewing will probably be in the Fall/Winter months.
 They are, of course, assuming that you are working with excellent dark skies far away from any light pollution, but don't let that fact put you off letting your eyes adapt.
 This is not a good way to assess the night sky; instead give your eyes a few minutes to adapt to conditions.
 You can sit in a chair and look up at the sky and you can actually see the effects: More and more stars will seem to 'appear'.


Choose Your Targets Wisely

Even with all these hints, you should be be judicious in what you want to view in the urban night sky.
 Targets you should consider instead would be:

The Moon: The moon is utterly unaffected by light pollution.
 Keep in mind that the best time to view the Moon is when it is waxing or waning, not when it is full.


The Planets: Jupiter, Saturn, Mars and Venus are also little affected by light pollution.
 Venus and Mars can also be enjoyed, however the former is very bright and shows only its crescent shape, whereas viewing the latter is often dependent on how close it is to Earth.
 The Orion Nebula is one of the easiest objects to find in the night sky, while the Andromeda Galaxy can it least be partially seen on clear nights from the city.


In Conclusion

Urban astronomy will never match finding true dark skies far out in the country, but don't let naysayers tell you that you ""Can't see anything in the city"".


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