Livestream Lecture - August 17, 2022

7:00 PM, Wednesday, Live-streamed via Zoom, YouTube and Facebook

“The World’s Largest International Dark Sky Reserve”


Stephen Hummel, U of Texas, Austin, McDonald Observatory
Amber Harrison, International Dark Sky Association, Tucson

Over the past 100+ years, the world's night skies have been rapidly vanishing due to the spread of light pollution. Thankfully, easy solutions to light pollution exist. In a remote region of West Texas and Northern Mexico, astronomers, conservationists, parks, and many communities have teamed together to form the largest area in the world where the night sky is protected: the Greater Big Bend International Dark Sky Reserve. The reserve is not only the largest of its kind at over 15,000 square miles in area, but also the first such reserve to cross an international border. At the core of the reserve is the University of Texas' McDonald Observatory, home to one of the largest telescopes in the world. McDonald Observatory has worked with surrounding communities for decades to promote better lighting practices to preserve our night skies, without requiring people to live in darkness. Stephen Hummel will discuss the impact of artificial light as well as the strategies that have led to the reserve's success. 

Click here for how to view the lecture.


Membership brings with it many benefits, including access to:


Free and open to the public as well as to members, the SFAA hosts a distinguished list of guest speakers throughout the year. Our Speaker Series attracts leaders from astronomy, physics and related disciplines who share with SFAA members and the general public the latest developments from cutting-edge scientific programs. The Series invite experts from nearby NASA-Ames, Stanford, SETI, UC Berkeley, UC Santa Cruz, as well as speakers throughout the US via live-stream.


Star Parties

Each month the SFAA hosts member-only viewing atop Mount Tamalpais in Marin County. Private viewing nights like this are one of the great benefits of SFAA membership, offering peaceful viewing, with no street lights, great range of visibility from the site, (bathrooms!) and the opportunity to network with fellow astronomers. This venue is truly wonderful because it is almost always ‘above the fog’, making viewing especially ideal when the city lights are blocked by the marine layer. Many nights we can see the Milky Way in all its glory!



Special Events

Each year the SFAA hosts members-only camping and star parties at Glacier Point in Yosemite National Park in coordination with the National Park Service. Other member-only events have included night-time tours of Lick Observatory and weekend camping and star parties at the Robert Ferguson Observatory in Sonoma County. The SFAA works with schools and universities to bring telescopes to Science and Astronomy nights throughout San Francisco and Marin.


Telescope Loans

The SFAA has a number of telescopes that it loans to members who are just starting out to discover the world of astronomy and night sky viewing. The available equipment includes simple-to-use Dobsonian telescopes, computerized "go-to" telescopes, as well as numerous telescope accessories. New users are encouraged to attend member-only star parties so they can be tutored by more experienced members on how to setup their loaner scopes and to plan their viewing session.