Welcome to the Peninsula Astronomical Society

The Peninsula Astronomical Society (PAS) is a group of Bay Area astronomy enthusiasts of all ages and backgrounds. We hold monthly meetings (always online, these days) featuring invited speakers and covering diverse topics in astronomy. Learn more about PAS.

Upcoming Talk

Join PAS as we host UC Santa Cruz Professor and renowned astronomer Enrico Ramirez-Ruiz, who will talk about the origin of heavy elements in our universe. The talk is free of charge and open to all, so bring a friend or family!

Cosmic Alchemy In the Era of Gravitational Wave Astronomy

The source of about half of the heaviest elements in the universe has been a mystery for a long time. Although the general picture of element formation is well understood, many questions about the astrophysical details remain to be answered. Here I focus on recent advances in our understanding of the origin of the heaviest and rarest elements in the Universe.

About Our Speaker

Enrico Ramirez-Ruiz is a Professor and the Vera Rubin Presidential Chair at the University of California, Santa Cruz (UCSC). After studying at the University of Cambridge, he was the John Bahcall Fellow at the Institute for Advanced Study in Princeton. Since joining the UCSC faculty in 2007, Ramirez-Ruiz has won a number of awards for his research, including a Packard Fellowship, the NSF CAREER Award, the Radcliffe Fellowship at Harvard, the Niels Bohr Professorship from the Danish National Research Foundation, the HEAD Mid-Career Prize from the AAS and the Bouchet Award and the Dwight Nicholson Medal from the American Physical Society. He is a fellow of the American Physical Society and member of the Mexican Academy of Sciences and the American Academy of Arts and Sciences. Professor Ramirez-Ruiz is eager to understand our origins and disruptive events in the night sky. He works with computer models to understand the cataclysmic death of stars and recently led efforts to uncover the origin of the heaviest elements in the universe. Ramirez-Ruiz tests out his theories with complex computer simulations that defy the boundaries of human experience and the assumptions we make about the universe. He has authored or co-authored about two hundred and eighty research papers, two dozen in Science and Nature. He has lectured, broadcast and written widely on science and is a highly decorated teacher and research adviser. As the director of the Lamat Institute, he works vigorously to support the promotion and retention of women and historically marginalized students in STEM.

Foothill Observatory Open 1st and 3rd Fridays

The Foothill College Astronomy Department and Peninsula Astronomical Society (PAS) have reopened public viewing programs at Foothill College Observatory the 1st and 3rd Friday of each month, from 9 p.m. to 11 p.m.

Since we are still dealing with COVID, we are adopting the following guidelines to enable safe operation of the Observatory for both our public visitors and our PAS operators.  We ask that visitors please agree to complying with these guidelines before visiting the Observatory, and to direct any questions to info@pastro.org.


  1. Full vaccination against COVID-19 is required to visit the Foothill College campus — This is a College requirement detailed on the Foothill College COVID-19 Behavioral Expectations page.
  2. Mask usage is required anytime visiting the Foothill College campus — This includes the Observatory, per the same college policy linked above in item 1.
  3. The number of visitors allowed inside the Observatory is reduced — To avoid overcrowding within the limited space, please wait outside the observatory until a PAS telescope operator lets you and your group inside. Once your group is done viewing through the telescope, you will exit the Observatory so that a new group may enter. 

More about FootHill Observatory | Map & Directions | Foothill Webcam

Recent Events

Lunar Eclipse Illustration by NASA
Image: NASA.gov

May 2022 –– Total Lunar Eclipse Party at Foothill Observatory May 15!

The Peninsula Astronomical Society and the Foothill College Astronomy department held telescope observations of the total lunar eclipse on Sunday, May 15 from 8:30 to 10:30 p.m.

We observed the eclipse using a range of portable telescopes, as well as the Foothill College Observatory. You can see a few photos on our PAS Flickr account.

For background on lunar eclipses, and this one in particular, check out NASA’s What You Need to Know About the Lunar Eclipse.

See our Past Meetings page for more events and recordings.

Quick Links

About PAS | PAS Membership | Foothill Observatory | Oak Ridge Observatory | info@pastro.org