There are a lot of changes coming in the world of street lighting that could have a major impact on operations at Palomar Observatory. For a short perspective on it have a look at this recent article in the San Diego Union Tribune newspaper.
In summary there is a big push to convert away from the astronomy-friendly low-pressure sodium lighting installed to help protect Palomar Observatory in favor of full-spectrum lights. These full spectrum lights are rich in blue light which disproportionately brighten the night sky. While the lights will be dimmer and thus save energy, their impact on astronomical research will be felt.
The International Dark-sky Association has come out against such changes. You can read their research paper Visibility, Environmental, and Astronomical Issues Associated with Blue-Rich White Outdoor Lighting here. A shorter, summary piece Seeing Blue is here.
While these are big issues for cities and organizations to sort out don't forget that you can make a difference right at your own home. By choosing to turn off unneeded lights or installing a dark-sky friendly light fixture you can improve the sky for everyone in your area. If your area happens to be San Diego County, don't forget that thanks to SDG&E Dixieline Hardware now has a great deal on lights that are dark-sky friendly.