Our 33rd Season Zoom Presentations

Oct 16, 2021: Galactic Archaeology: Galaxy Assembly with Globular Star Clusters

Globular star clusters are among the oldest objects in the Universe. Accordingly, they can provide valuable information about the early evolution of the galaxies they inhabit. This presentation, focusing on the Milky Way and Andromeda galaxies, will show what globular clusters reveal about their host galaxies' chemical composition. We will also explore the mysteries that still surround globular cluster formation, and possibilities for future observations.

Our speaker, Charli Sakari, is an Assistant Professor of Physics & Astronomy at San Francisco State University.

Sep 11, 2021: Advanced Instrumentation in Optical Astronomy

Ground-based telescopes have come a long way in recent decades. Today they can take advantage of adaptive optics systems that reduce the effect of atmospheric image distortion, and, also, of fast compact computers that allow small telescopes to reach the capability of large telescopes. The result is a lively community of citizen astronomers who (among other things) can detect exoplanets and help study the size, shape, and trajectory of near-Earth asteroids.

Our speaker, Franck Marchis, is a Senior Planetary Astronomer at the SETI Institute's Carl Sagan Center. Also, he is Chief Scientific Officer at Unistellar, maker of citizen scientist telescopes.

Aug 14, 2021: Unveiling the Dark Universe with the Dark Energy Survey

Throughout history, the Universe has had a way of turning our grandest thoughts upside down. Now, we see that the cosmos is dark: dominated by dark matter and dark energy. With the Dark Energy Survey imaging 1/8th of the night sky — and mapping more than 100 million galaxies — we can get a clearer understanding of the vast Universe we call home.

Our speaker, Alexandra Amon, is a Postdoctoral Researcher (Kavli Fellow) at Stanford University.

July 17, 2021: Oumuamua: Interstellar Visitor

In 2017, astronomers detected an elongated object swinging past Earth on its way out of the solar system. The size, shape, and motion of Oumuamua (roughly “scout” in Hawaiian) inspired a few excited researchers to suggest the visitation of an interstellar “spaceship." This presentation will explore the physical nature of Oumuamua and a vast fleet of its extrasolar cohorts.

Our speaker, Douglas Lin, is a Professor of Astronomy and Astrophysics at University of California, Santa Cruz. He is also the founding director of the Kavli Institute for Astronomy & Astrophysics at Perking University.

June 19, 2021: Deep Prediction: Forecasting on Time Scales from Microseconds to Eons

Scientific forecasts span a staggering breadth of time scales, and they range in precision from vague & qualitative to exact & quantitative. This presentation will provide an overview of predictability. We’ll look at examples drawn from trading, meteorology, celestial mechanics, and cosmology. Finally, we'll end with the latest research-based forecasts for what will happen to the Universe in the extremely distant future.

Our speaker, Dr. Greg Laughlin, is a Professor of Astronomy at Yale University. He is co-author of The Five Ages of the Universe and co-founder of the online prediction aggregator Metaculus.

May 15, 2021: Gravitational Lensing: Bends in Spacetime

One hundred years ago, Einstein predicted that light rays would bend in the space near a massive object — much as light rays refract in an optical lens. Today, we use this fact to weigh galaxies, to discover planets of other stars, and to “see” invisible black holes. How did this idea of gravitational lensing come about, and how do we use it today to probe all fields of astrophysics?

Our speaker, Fatima Abdurrahman, is a fifth year PhD student and researcher in the Astronomy Department at University of California, Berkeley.

Apr 17, 2021: Black Hole Portrait: How We Got Our First Picture

Black holes are among the most remarkable predictions of Einstein's theory of gravity: so much material is compressed into such a small volume that nothing, not even light, can escape. Black holes have also captured the public imagination, and are commonly featured in popular culture, from Star Trek to Hollywood movies. In Spring 2019, the multinational Event Horizon Telescope (EHT) released the first real (non-Hollywood!) picture of gas around a black hole and the “shadow” cast as that gas swirls in. How did the EHT do it, and what have its combined observations taught us about black holes?

Our speaker, Eliot Quataert, is a Professor of Astronomy and Astrophysical Science at Princeton University. He has received numerous national awards for his research including a Simons Investigator award and the American Astronomical Society's Warner Prize. Dr. Quartaert is an elected member of the American Academy of Arts and Sciences AND of the National Academy of Sciences.