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Postcard from Mexico: why galaxies spin

I am a doctoral candidate in astrophysics at York University. My research focuses on how and why galaxies spin. The motivation for this topic is quite simple: my supervisor Dr. Marshall L. McCall recently discovered using 3-D data, that the spins of our universe’s neighbouring galaxies are organized relative to one another.

Most previous studies of spin in real galaxies were done in 2-D, so Dr. McCall’s study has changed the discussion of galaxy spins in the astrophysics community. This spin organization is at odds with established theories of spin alignment in our “neighbourhood of galaxies”. Understanding spin alignment provides insight into how this neighbourhood emerged and evolved. It can also help us answer the question “Why do galaxies spin the way they do?”

A researcher requires two things to answer this question: first, copies of our cosmic neighbourhood in the real universe (no simulations here – we are after what our actual universe is telling us!); and second, the 3-D spins of the galaxies in these copies. As a master’s student, I created pattern recognition software that identifies “copy neighbourhoods” in our universe. Among nearly 1.2 million galaxies in our nearby universe, the software recognized 174 copy neighbourhoods. Measuring their galactic spins in 3-D requires a special data set not readily available in the astronomy community’s Big Data archives. So I needed to travel to a telescope and acquire my own specialized data set for the galaxies in my copy neighbourhoods.

I travelled to Sierra de San Pedro Martir, Baja California, Mexico, to collaborate with Prof. Michael Richer at the National Autonomous University of Mexico’s Institute of Astronomy. The institute has a telescope that can gather spectroscopic data, which is a photo of the rainbow of light of an astronomical object. This data allowed me to understand how the galaxies were spinning with no guesswork attached!

Astronomy targets are not visible all year long, so I needed to apply for telescope time every couple of months to get observations of my targets. In total, we observed 316 galaxies, which required nine trips to the telescope, totalling 31 nights of observation over 16 months.  I was able to stay longer and collaborate in person at the Institute of Astronomy because of the Mitacs Globalink Award. This was paramount not only to further my education, but to establish better relationships with my collaborators.

On a simpler level, the Award allowed me to experience an education in life beyond my academic pursuits. This sort of immersive education is often overlooked during a PhD. Living in a foreign country in a different culture with new friends helped me hone the skills I needed to thrive outside my comfort zone. This is invaluable for researchers who want to be a positive influence in a work setting that requires excellent communication skills, both in terms of delivering information and supporting colleagues in pursuit of a shared goal. I would encourage every PhD candidate — regardless of their field of study— to study internationally, as their greatest education in life is γνῶθι σεαυτόν (to know thyself). 

Mitacs would like to thank the Government of Canada and the Government of Quebec their support of the Globalink Research Award program. In addition, Mitacs is pleased to work with international partners to support this award, including Campus France and Inria, India’s Ministry of Human Resource Development, the Japan Society for the Promotion of Science, and Tunisia’s Ministry of Higher Education and Scientific Research and Mission Universitaire de Tunisie en Amerique du Nord.