Author Topic: Best Light pollution map?  (Read 904 times)

freddormasa

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Best Light pollution map?
« on: December 24, 2017, 02:34:12 PM »
Anyone know what the most accurate map is?



arovuzar

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Re: Best Light pollution map?
« Reply #1 on: December 29, 2017, 02:47:49 AM »
A lot of folks use this one -https://www.lightpollutionmap.info
Click on the red Atlas in the menu in the upper right. Then when you click on various spots, it will give Bortle rating as well as the one I don't understand as much.

percufareg

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Re: Best Light pollution map?
« Reply #2 on: December 29, 2017, 04:21:15 AM »
Quote
A lot of folks use this one -https://www.lightpollutionmap.info
Click on the red Atlas in the menu in the upper right. Then when you click on various spots, it will give Bortle rating as well as the one I don't understand as much.

This is Fabulous... thank you..
Iclicked on the VIIR2017 and thought it was even better than the Atlas...
although the Bortle rating was helpful the Constellation star map counter was good too...

Jason Meyer

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Re: Best Light pollution map?
« Reply #3 on: January 08, 2018, 02:23:07 AM »
Quote
A lot of folks use this one -https://www.lightpollutionmap.info
Click on the red Atlas in the menu in the upper right. Then when you click on various spots, it will give Bortle rating as well as the one I don't understand as much.

I like that map as well, Jim.

I had class 2 skies in my backyard back home, now I live under class 5 and best I can do within an hours drive is class 4.

writgobetfcoo

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Re: Best Light pollution map?
« Reply #4 on: January 08, 2018, 01:23:53 PM »
Quote
Quote

A lot of folks use this one -https://www.lightpollutionmap.info
Click on the red Atlas in the menu in the upper right. Then when you click on various spots, it will give Bortle rating as well as the one I don't understand as much.

This is Fabulous... thank you...
You are welcome. I have been using this and Google Earth to find some dark skies "near" my house. It can be a real time sink, but dark skies are worth it!

Eric Mannasseh

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Re: Best Light pollution map?
« Reply #5 on: January 09, 2018, 07:32:49 AM »
Quote
Quote

A lot of folks use this one -https://www.lightpollutionmap.info
Click on the red Atlas in the menu in the upper right. Then when you click on various spots, it will give Bortle rating as well as the one I don't understand as much.

I like that map as well, Jim.

I had class 2 skies in my backyard back home, now I live under class 5 and best I can do within an hours drive is class 4.
Alan - you are pretty far from where they hold the Okie-Tex Star party? I was going to check that out after I moved to Fort Worth, but it is really far - seems like 400 miles - we tend to forget distances involved with the panhandles of our states.
I'm going to join the TAS out of Dallas - their dark site is near Atoka. Much closer for me and I think it is a class 3.

erafquacor

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Re: Best Light pollution map?
« Reply #6 on: January 10, 2018, 05:20:58 AM »
Yeah, its just over 400 miles for me as well but might be worth the trip next year.

obenanus

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Re: Best Light pollution map?
« Reply #7 on: January 10, 2018, 08:53:17 AM »
Quote
A lot of folks use this one -https://www.lightpollutionmap.info
Click on the red Atlas in the menu in the upper right. Then when you click on various spots, it will give Bortle rating as well as the one I don't understand as much.


Unfortunately, this map system is quite inaccurate. I find that for New York and New England locations it typically provides values significantly too low on the Bortle scale for even modestly populated areas, while at the same time rating darker semi-rural locations as far too bright.

BrooksObs

risodachest

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Re: Best Light pollution map?
« Reply #8 on: January 11, 2018, 01:34:21 AM »
Seems like many members like this map; it's pretty accurate for my location; however I'm not in a populated area.

ersteadviastun

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Re: Best Light pollution map?
« Reply #9 on: January 11, 2018, 11:29:02 AM »
I don't have a dark sky meter (yet) to verify my location readings. I do know for Houston it seems to reflect what we have. I was in an IDA dark site last weekend which showed as Bortle 2/3 on the map and it was DARK and seemed to match the descriptions in the Bortle chart. I just look for anything better than a class 9 sky where I live and figure it can get me close to 3 and lower classes. I'm probably going to be happy with a 4/5, but a 1 or 2 in reach via RV would be great. If a 2 is really a 1, then I have won a bonus.

Jack Hillian

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Re: Best Light pollution map?
« Reply #10 on: January 13, 2018, 05:38:20 AM »
If you don't agree with World Atlast 2015 prediction about a certain place, you can always submit your SQM measurement using tools on the map and it may be eventually used for calibration in the next generation of the World Atlas. In the meantime anyone can see your measurement and see the real situation. The Bortle scale on the map is just an estimation because not only it is a subjective scale but also it's calculated only from the zenith sky brightness parameter (taken from https://www.handprin...TRO/bortle.html) which may be not enough for accurate results.

tiostaralzo

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Re: Best Light pollution map?
« Reply #11 on: January 13, 2018, 06:11:56 AM »
Despite any flaws, these maps still give you an idea of where to start looking look for dark(er) skies and where not to expect them.

Tyler Cox

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Re: Best Light pollution map?
« Reply #12 on: January 16, 2018, 02:58:32 AM »
The reason I was asking is for that reason. They seemed to show different results. Some said I was in a yellow zone while some said I was in a light green light blue area which is a big difference.

tradneedcoegen

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Re: Best Light pollution map?
« Reply #13 on: January 16, 2018, 03:29:20 AM »
It helps if you zoom down on your street,and I clicked on VIIR2017... it seemsclearer...

Regardless of Bortle, I do know my immediate horizon and where we have dark sites w/others for viewing ...
For now I like it...to get any darker here I would have to be in the FL Everglades...and even then the lights of Miami & Naples might have to be contended with...

ransgesislu

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Re: Best Light pollution map?
« Reply #14 on: January 17, 2018, 01:52:45 AM »
Quote
If you don't agree with World Atlast 2015 prediction about a certain place, you can always submit your SQM measurement using tools on the map and it may be eventually used for calibration in the next generation of the World Atlas. In the meantime anyone can see your measurement and see the real situation. The Bortle scale on the map is just an estimation because not only it is a subjective scale but also it's calculated only from the zenith sky brightness parameter (taken from https://www.handprin...TRO/bortle.html) which may be not enough for accurate results.

Unfortunately, this so-called formula cited for use in converting the Bortle Dark Sky Scale to a simple numerical calculation will do nothing of the sort. The Bortle Scale classifications are based on the observer's evaluation of the appearance of much of, if not the entire, appearance of sky features. The author of the formula linked to above is a numerical interpretation based on just the observer's limiting magnitude, which is very far from the Bortle Scale and is certainly no worthy substitute.

BrooksObs