Speaker:

Laurie Rousseau-Nepton, Assistant Professor David A. Dunlap Department of Astronomy & Astrophysics & Dunlap Institute for Astronomy and Astrophysics

Talk Title:

Rediscovering the History of Astronomy through the study of Ancient Observatories

Date and Location:

Thursday, February 12, 2026

3–4 p.m.

BA 5166 (DGP seminar room) and online. Zoom registration link for virtual attendance.

Reception to follow

There is no registration required to attend this event in person. However, seating is limited, so arriving early is recommended.

Abstract:

“What did ancient astronomers know? When and how did they acquire this knowledge? How did they understand the universe?” Recently, I have studied the astronomical design of two medicine wheels (MW) stone circles, one in Alberta, Canada known as the Majorville/Iniskim Umaapi site and the other in Wyoming, known as the Bighorn MW. Although their Astronomical purpose is still debated, I hope to shed some light into how they were used and the secrets (or I should say message) that they hold. MWs have been used by First Nations and Native American tribes for generations. In this work, I developed a new methodology that uses state-of-the-art land survey data to reconstruct the MW sites' horizon and the orientation of the stone structures. I developed tailored analysis tools to precisely model the light path of celestial objects in the atmosphere through different epochs. The results are surprising and I hope will inspire people to look into these sites in more depth. The name medicine wheel comes from a deformed translation from Native languages and means mysterious circles. Let’s make them a bit less mysterious.

Biography:

Laurie Rousseau-Nepton is a new faculty at the University of Toronto and the Dunlap Institute for Astronomy and Astrophysics. She comes with six years of experience working as a resident astronomer at the Canada-France-Hawaii Observatory supporting various astronomical instruments. Laurie, is currently leading an international project called SIGNALS, the Star formation, Ionized Gas, and Nebular Abundances Legacy Survey, which sampled with the SITELLE instrument more than 50,000 of star-forming regions in 40 nearby galaxies to understand how the local environment affect the young star clusters characteristics. In her lab, she develops a new kind of highresolution spectro-imager which includes sensitive quantum detectors. She is also dedicated to find new ways to do science where the local cultures and the diversity of world views becomes an important part of teaching and research. This past year, she extended her work into the field of Archaeoastronomy. She will be sharing some of the latest rediscovery in connection with important Indigenous sites.