The Dark Matter Mystery • Katie Mack • ISS2025

The matter we see in the Universe — all the stars and planets, the galaxies and clusters — is really just a small fraction of all the stuff out there. Normal matter is dwarfed by vast quantities of mysterious Dark Matter: we know it's out there ... we're just not sure what it is yet. Which is a little embarrassing, but also really exciting for the astrophysicists! ———————————————— Prof. Katie Mack is the Hawking Chair in Cosmology and Science Communication at the Perimeter Institute in Waterloo, Canada. In this video she is speaking to students at ISS2025: Quanta to Quarks, the 44th Professor Harry Messel International Science School, held at the University of Sydney, Australia, in July 2025. Katie's second lecture at ISS2025 on The End of the Universe:    • The End of the Universe • Katie Mack • ISS...   Check out the ISS2025 Playlist:    • ISS2025: Quanta to Quasars   For more about the ISS: http://sydney.edu.au/science/iss