A new radio survey reveals that the Milky Way’s magnetic field is intricate, widespread, and deeply connected to how the galaxy is organized.
An international team led by UBC Okanagan has produced the sharpest picture yet of the Milky Way’s magnetic field, and the view is anything but simple. The findings show that this vast, invisible structure is far more intricate than scientists once thought.
The project is led by Dr. Alex Hill, an assistant professor in the Irving K. Barber Faculty of Science at UBCO who specializes in radio astronomy. Based at the Dominion Radio Astrophysical Observatory (DRAO) near Penticton, Hill and his colleagues analyzed observations from the DRAO 15-metre telescope to create the first broadband map of Faraday rotation. This effect allows researchers to trace magnetic fields by measuring how radio waves change as they travel through space, providing coverage across the northern sky.
That all sky map comes from the Dominion Radio Astrophysical Observatory GMIMS of the northern sky (DRAGONS), a dataset led by former UBCO postdoctoral researcher Dr. Anna Ordog. By capturing polarized radio emission across a wide span of frequencies, DRAGONS can separate overlapping magnetic features along the same line of sight and reveal structures that previously blended together or disappeared in narrower surveys. The project is one piece of the Global Magneto-Ionic Medium Survey (GMIMS), launched by Dr. Tom Landecker, a DRAO astronomer and an adjunct professor at both UBCO and the University of Calgary.
