29 February 2012

Get Involved: Dark Skies

As an Urban Astronomer, I am enthusiastic about astronomy even in the light-polluted urban centers of the world, including my own city of San Francisco. I write this blog for many reasons, one of which is to remind city dwellers that there is still plenty to see in the night sky. Right here in San Francisco, there are ways to view the sky in a dark spot, away from streetlights and brightly-lit areas of the City, and see quite a bit of the night sky. Mainly you just need patience to let your eyes dark adapt your location, and before you know it you can find quite a few stars and constellations.

Over the past weeks, I was traveling in and around Flagstaff, AZ, the World's First International Dark Sky City. Flagstaff is a medium-size city of about 60,000 people, but through smart street lighting, has reduced its light output considerably. While visiting Lowell Observatory on a hill above Flagstaff, you could see the city lights below, but it was not like any other I had seen. Clearly there was light from the city, but it was subdued, not shining up in the sky but rather shining down onto the streets and public spaces. That is Smart Lighting!

There is a global organization called the International Dark-Sky Association that provides advocacy and education to support communities and municipalities around the world to learn about smart lighting and preservation of dark skies. I applaud their efforts and their mission. Locally in San Francisco fellow SFAA member Dave Goggin has organized a list and invites participation in San Francisco discussions about lighting.

What can you do in your community to preserve dark skies? I am sure the Dark Sky Association would welcome your participation. It's a very grass roots thing. Here is an article about an individual in San Clemente starting a movement there. Get inspired!

5 comments:

Ed Wawrzaszek said...

I was there two years ago and fell in love with the area. I hope to retire there in the not to distant future.

Kenji Matsuoka said...

I just found out that SFPUC is going to replace 18,500 street lamps with LED lamps: http://sfwater.org/bids/projectdetail.aspx?prj_id=270

I just sent them an email asking whether the new lamps will be better at directing their light than the existing ones.

The Urban Astronomer said...

hi Kenji - thanks for following up with SFPUC. This could be a chance to really cut down light pollution, since they are touching every street lamp, they should incorporate basic Smart Lighting techniques.

-- Paul

Kenji Matsuoka said...

Here's what I heard back from Kenya Briggs at SFPUC:


The situation you describe is likely to improve after the LED street light conversion. LED street light have better optics than the high pressure sodium lamps that are currently installed on San Francisco streets. LEDs have more controlled light distribution than high pressure sodium lamps.


I followed up asking what particular model of LED lights they're planning to use.

The Urban Astronomer said...

Terrific, Kenji. Glad to hear that, and I hope this means that San Francisco can start to move in the direction of Flagstaff.

-- Paul