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The Webfooted Astronomer - January 2001


Minutes: I Saw the Light (Not!)

By Greg Donohue

THE Annual SAS Awards Banquet is fast approaching. There will be great food, great fun, and lots of great door prizes (not to mention a poster of Dr. Fiorella Terenzi)! RSVP by January 5 using the form on page 6 in this newsletter.

The December SAS general meeting was held early this year, for two reasons. First, the normal third Wednesday put us in the middle of the holiday season. But second, and more importantly, it allowed us the privilege of being addressed by Dr. David Crawford, Executive Director of the International Dark-Sky Association (IDA).

Dr. Crawford's visit with us was a follow-on to a very successful full day conference hosted by Dark Skies Northwest, the regional section of the IDA chaired by the SAS's very own Bruce Weertman. Here is an excerpt from the December issue of the IDA newsletter about the conference:

"Kudos to Bruce Weertman, chair of DSNW, for organizing this conference where attendees learned much about responsible lighting design, savings from good lighting, and how to preserve our nighttime environment."

In addition to volunteering his time as Executive Director of the IDA, Dr. Crawford is Emeritus Astronomer at Kitt Peak National Observatory, where he worked as a staff astronomer from 1960 to 1995. He did work on stellar photometry, which he claims is the kind of work everyone uses, but won't make you famous! He got his Ph.D. from the University of Chicago the same year that Sputnik went into orbit, doing his graduate work at the same time and place as the late Dr. Carl Sagan.

The IDA began in 1988. But it soon became apparent that the issues were broader than just southern Arizona, and broader than just the field of astronomy, so a non-profit organization was formed, with about 50 members to start. Today the IDA has more than 6,200 members worldwide, and 5 paid full-time staff.

The IDA's goal is to preserve the nighttime environment by educating everyone, everywhere about the advantages of dark skies and good outdoor lighting.

Now at this point, in the interest of journalistic integrity, I have to confess that before the meeting, I was one of those amateur astronomers who had never joined the IDA! Though I felt guilty about it, and though I thought the IDA's cause was a noble one, I also felt that, sadly, it was a lost cause (just look up your local night sky, or lack thereof). But Dr. Crawford's presentation helped me "see the light (not!)," so I joined the IDA at the end of the meeting, and am also buying an IDA gift membership for the mayor of Woodinville!

For me, the key to changing my mind about the IDA came from seeing the issue not just as one of annoyance to astronomers, but as a much larger safety and environmental issue affecting not only all humans, but wildlife and plants as well. The IDA is not an astronomy organization; it is a quality lighting and nighttime environment group.

Bad outdoor lighting has many negative impacts, including: giving people a false sense of security; harming plants and wildlife (most animals are active at night); interfering with our circadian rhythms, raising our stress levels, and thus adversely affecting our physical and mental health; and wasting an estimated $2 billion a year lighting up the bottoms of birds!

Glare (blinding light) is a major problem with outdoor lighting, resulting in unsafe conditions. We don't use bare bulbs in our homes, so why do we allow so much glare and wasted light outside? With many conventional lighting systems, only 10-20% of the light goes where it is needed and the rest is wasted. There is no longer any real excuse for this, since the technology is available to eliminate glare, direct the light only to where it is needed, and use much less energy (2-4 times less) in the process. Thanks to the energy savings, the payback for installing good lighting systems is usually only 3-5 years. What we need is more visibility, not more light!

Dr. Crawford did a little demonstration with a 60-watt light bulb showing that it is really a heat source that just happens to produce light. Only 10% of the energy goes into producing light; the other 90% goes into generating heat. This demonstration vividly shows the effects of energy waste, glare, and luminous overload, and can be used equally well with the city council, kindergartners, or even graduate astronomy students (grin).

The IDA has received many awards and lots of good press coverage as of late, including articles in Time, Economist, and Mother Earth magazines. All major international lighting organizations now include IDA concerns in their materials. Many cities (such as Sydney, Melbourne, Rome) and states (Arizona, New Mexico) have new lighting policies, and are striving to be known for their dark skies. The IDA also makes videos and slide sets available, and gives out awards. They will soon have Microsoft PowerPoint presentations available on their Web site. The IDA wants to do much more. But to accomplish that, they need a viable budget, and that requires more memberships. If you have not already joined, please considered doing so. Let's work together to recapture and preserve our nighttime environment!

At the end of the meeting, Brian Allen moved that the SAS board consider incorporating IDA dues (perhaps at a reduced rate, and perhaps as an option) into the SAS membership dues as a way of supporting IDA. Some expressed concern about raising the cost of SAS dues. Dave Crawford said that IDA would consider discounted IDA dues for SAS as a possible model for other astronomy clubs. No official vote was taken on the motion, but general consensus was that the board would take up this issue and develop a formal proposal.

International Dark-Sky Association Web site:
Dark Skies Northwest Web site:

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