Here be DRAGONS: Revealing the three-dimensional structure of the local Galactic magnetic field

Like the Sun and the Earth, our Galaxy has a magnetic field. Earth's field shields us from the solar wind, while the Sun's field protects the Solar System from cosmic rays. The Galactic magnetic field (GMF) is also essential: it influences star formation and supports the structure of the Galactic disk. However, measuring this field is challenging as magnetic fields are not emission sources that can be observed with a telescope. Instead, we observe the GMF indirectly by measuring Faraday rotation, the change in polarisation angle that occurs when a linearly polarised wave passes through a region containing a magnetic field and free electrons. My research uses DRAGONS, a radio polarisation survey observed at the Dominion Radio Astrophysical Observatory in British Columbia. With the highest resolution Faraday rotation measurements of the Northern sky ever obtained, DRAGONS offers an unprecedented opportunity to study the three-dimensional structure of the GMF with a high degree of detail. In my presentation, I will share a new model that describes the geometry of the GMF within 1 kpc of the Sun, a step toward solving the puzzle of how magnetic fields form, evolve, and influence our Galaxy.