ASX: Why are U of T astronomers investigating the mass of the Milky Way?
What is the mass of the Milky Way galaxy, and why is it important to investigate?
Dr. Gwen Eadie, an Assistant Professor jointly appointed between the University of Toronto’s David A. Dunlap Department of Astronomy & Astrophysics (DADAA) and its Department of Statistical Sciences (DoSS), spoke on these questions at the Astronomy and Space Exploration Society’s first Star Talk of the year on July 8. She discussed her research team’s investigations into the universe guided by statistical studies.
The structure of our universe
The galaxies of our universe — which includes the Milky Way — cluster into the shape of strings, noted Dr. Eadie.
“To recreate this hierarchical structure in computer simulations of how the universe evolved, we’ve discovered that you have to include something called dark matter,” Dr. Eadie noted. Dark matter is a hypothetical, currently undetectable type of matter that has a gravitational effect on visible matter — but does not otherwise interact with it.
Astronomers believe that every galaxy in the universe, including the Milky Way, lives inside its own dark matter halo, continued Dr. Eadie. This structure of dark matter “represents a really large portion of the mass of the galaxy.”