Estimating Light Pollution Levels
Posted 08 February 2013 - 08:46 AM
There must be a technique to estimate your actual light pollution level? Such as naked eye viewing of a specific constellation and determining what magnitude stars can be seen?
Posted 08 February 2013 - 11:32 AM
I have used this. According to this map my location is on the boundary between yellow and green.
The map gets pretty coarse when you get to about 1:500,000 scale, but is a good starting point to determine relative scale between different locations. Pretty handy if you are planning a trip somewhere and are interested in the light pollution level at your destination.
We might finally have some cloudless skies this weekend. I will see what magnitude stars I can see from my property, then compare that to the scale.
Posted 08 February 2013 - 12:00 PM
Currently, the Globe at Night program is soliciting new data from the public ( GaN Family Activity Packet pdf ). This pdf has magnitude charts that are easy to use. They also have an interactive website you can use for real-time observations ( GaN webapp ).
The Globe at Night website, along with the International Dark Sky Association and our own Light Pollution Forum are great resources.
Posted 08 February 2013 - 12:30 PM
Well that's embarrassing. I totally missed the Light Pollution forum! Thanks for the links.
Posted 08 February 2013 - 12:35 PM
Posted 09 February 2013 - 05:55 PM
Posted 09 February 2013 - 06:50 PM
Now I need to wait for the winter cloud to dissipate.
Posted 10 February 2013 - 11:37 AM
After 15 minutes, and with plenty of snow in the backyard, I was able to see to 3.5. I hope this will improve after the snow disappears, I stay out longer to acclimate my eyes, turn off more of the household lights. More trials will be required.
I have lots of hills and trees to work around, distant glow from Penticton to the SW, and local street lights to contend with but my backyard should be workable.
My binoculars should arrive this week. With those and SkySafari I should get a good sense of what I can see from the backyard and for what objects I will need to find a darker site. And perhaps later this year I will get a telescope.
Posted 10 February 2013 - 12:51 PM
Posted 10 February 2013 - 01:09 PM
What magnitude can you normally see naked eye in Penticton?
Posted 11 February 2013 - 12:16 AM
Posted 13 February 2013 - 01:23 AM
Those of us familiar with a lot of truly dark sites would break down his best two scale levels into about 5 different levels, but it works nicely if describing a site to another person and you don't know the SQM readings for the site.