UofT AstroTour: Discovering new galaxies through the eyes of a Dragonfly
When we observe the universe we see light from stars, gas and galaxies, but this makes up merely 4% of the universe. We think that a much larger fraction of the universe is made up of “dark matter,” which is invisible and only interacts through gravity. Dark matter is critical to how all the galaxies we see evolve, but the nature of dark matter is still a mystery. This talk tells the story of how the Dragonfly Telephoto Array, a compound-lens telescope with a revolutionary design that enables it to image faint, diffuse structures, is attempting to understand dark matter. So far, Dragonfly has discovered a whole new type of galaxy, named “ultra-diffuse galaxies,” that are extremely faint but extremely large. Even just looking more closely at two of these ultra-diffuse galaxies has turned galactic theory on its head: one of them has too much dark matter and another has too little – and not just by a small amount, there is 100 times difference in the ratio of dark matter to normal stars than what we’d expect.
About the Speaker
Deborah Lokhorst is a PhD candidate in the Department of Astronomy & Astrophysics and the Dunlap Institute at U of T. She is working with the Dragonfly Telephoto Array, designing a hardware upgrade to the telescope which she will use to image the extremely faint outskirts of galaxies to investigate galaxy formation and evolution. When not at work, she enjoys hiking and spending time outdoors.
The U of T Astronomy Public Tour, or AstroTour, is a monthly event operated by the graduate students of the U of T Astronomy Department. The Tour features a public lecture by a member of the Department on topics ranging from their research to great moments in astronomical history. Following the lecture, tour-goers can peer at the night sky through the Department’s balcony and dome telescopes, or watch a planetarium show run live by astronomer. Admission to the tour is free. Seating for the lecture is on a first-come, first-served basis (doors open ten minutes before the start of the lecture), and the telescope observing is walk-in.
Planetarium tickets will be handed out at 8:45pm outside of the lecture room on a first-come first-served basis. Any remaining planetarium tickets will be available after the talk.
Who can attend: Everyone
Fee: Free
Registration: Not required
Organized by: Graduate Astronomy Students Association. The AstroTours are generously financed by the Department of Astronomy & Astrophysics and the Dunlap Institute for Astronomy & Astrophysics.
Location: University of Toronto, McLennan Physical Laboratories (MP 103), 60 St George St., Toronto, ON M5S 1A7
http://www.astro.utoronto.ca/astrotours/?page_id=392
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