Past Event · Public Lecture

Cosmic Shadow Theater: Casting Light on Galaxies

Presented by Emmanuel Schaan

Register here to watch in person in the Kavli Auditorium, or watch the lecture live on our YouTube page.

The afterglow from the Big Bang, called the "cosmic microwave background radiation," serves as the backlight in a shadow theater where galaxies are the actors. The structure of galaxies is still mysterious despite ever-improving telescope observations, because many of their components – including dark matter and diffuse gas ­– are invisible in ordinary light. But we can indirectly detect these features by observing the shadows that galaxies cast on the cosmic microwave background radiation. The shadows  provide clues to how galaxies form and evolve, and help us to work out the nature of dark matter and dark energy in the universe. I will describe the efforts led by SLAC scientists to reveal these galaxy silhouettes, using cosmic microwave background experiments and galaxy surveys of unprecedented scale.

About Emmanuel Schaan

Emmanuel Schaan is a staff scientist at SLAC National Accelerator Laboratory. As a cosmologist, he studies the origin and evolution of the universe by analyzing data from large telescopes in the U.S., Chile and space. His work focuses on the cosmic microwave background, the earliest light visible after the Big Bang, and on the large-scale distribution of galaxies. Schaan grew up in Paris, France. After studying at Ecole Normale Supérieure, he moved to Princeton, where he received his PhD. in 2017, and then worked as a Chamberlain Fellow at Lawrence Berkeley National Laboratory before joining SLAC in 2022. He loves astrophotography, tinkering, electronics and DIY projects.

Past Event · Public Lecture

Cosmic Shadow Theater: Casting Light on Galaxies

Presented by Emmanuel Schaan

Public Lectures
video stillframe from public lecture
Thursday, July 27, 2023
7:00–8:00 p.m. PDT
Science and User Support Building (SUSB)
Attending a public event

Coming to SLAC

Free admission 
Registration may be required.

Identification required 
Adults are required to bring a photo ID to enter the SLAC campus.

Limited seating  
Please arrive early to join the event on time.

Free parking 
SLAC offers free parking in our visitor parking lot.

SLAC facilities meet American Disability Act requirements for accessibility. If you need assistance, please notify our security officers as you enter SLAC’s main gate, and they will direct you to a parking area and assist or escort you to the auditorium.     

Getting here 
SLAC is located at 2575 Sand Hill Road, Menlo Park, California, 94025. Please visit our Maps and directions page for driving directions. 

If you have specific questions or concerns about attending a public lecture at SLAC, please contact us.

Site entry informationMaps & directions