PDA

View Full Version here: : Earth Hour 2010 question


Esseth
08-03-2010, 02:40 PM
So I have started to notice that Earth Hour 2010 ads are starting to pop up and being the first year that my interest in Astronomy and Earth Hour correlate I was wondering if it would make much of a difference to viewing?

Doing the maths, Less light = Darker Skies, but being inner Brisbane suburbs would it make a noticeable difference to what I would be able to see. The scope I am using is a simple 8” Dob that typically faces N/E.

phranticsnr
08-03-2010, 03:11 PM
An interesting point. Honestly, I don't think Earth Hour is going to affect viewing conditions all that much.

There will still be an abundance of streetlights, security lights and commercial properties that will still be lit. Even the organisers of Earth Hour admit that it doesn't really make an impact on the world electrically (and as a corollary, luminously) - it's more about awareness.

ngcles
08-03-2010, 08:39 PM
Hi Esseth & All,



It makes little difference generally mainly because most people don't observe it and switch off their outside insecurity lights anyway. Plus, all the really big outside lights like shopping-centre car parks, football fields, street lights etc don't go off anyway.

I've spent Earth Hour as my "nearly dark" site out in the Southern Highlands over 100km from the Sydney CBD at New Moon and the hour of Earth Hour made no difference at all -- I measured it scientifically with an SQM dark meter. Nil, nada, zip ... a goose-egg.

I've also spent Earth Hour at Sydney Observatory almost in the middle of Sydney. It made a very slight difference at best -- maybe 2/10ths of a magnitude. The untrained eye would notice no difference at all.

You won't notice any difference at all this year. Earth Hour is only about 2 days before Full Moon which will be 90% illuminated completely obliterating any reduction in man-made light pollution.


Best,

Les D

Blue Skies
08-03-2010, 09:02 PM
I was going to point out the same thing, Les - with a nearly full moon its unlikely you'll notice any difference.

Vartigy
12-03-2010, 11:10 AM
We had a few blackouts recently over summer with the massive electrical storms we get out here.
I must say, quite enjoyed the evenings with no power, just sitting down with the candles lit, book in hand, bottle of wine open, and the mrs and the dog to keep company.
Quite a relaxing evening.
So we try and have an earth night around once a month.