With nearly $2 million in support, U of T astronomer to upgrade telescope in hunt for dark matter

An innovative, ground-breaking telescope named Dragonfly is about to undergo a major transformation thanks to nearly $2-million in support from the Canada Foundation for Innovation (CFI).

The Dragonfly Telephoto Array is a unique telescope designed to observe astronomical phenomenon such as extremely faint galaxies and the dark filaments of gas associated with many of them.

Dragonfly is the brainchild of Roberto Abraham, a professor of astronomy and chair of the David A. Dunlap department of astronomy and astrophysics in the University of Toronto’s Faculty of Arts & Science, and Pieter Van Dokkum, a professor of astronomy at Yale University.

The project is one of four at U of T that are being supported by CFI, according to an announcement that was released March 3 by Prime Minister Justin Trudeau and François-Philippe Champagne, the federal minister of innovation, science and industry. The other three U of T projects are headed by: Constantin Christopoulos, in the Faculty of Applied Science & Engineering; Professors Jennifer Gommerman and Kullervo Hynynen in the Temerty Faculty of Medicine; and Charles Boone and his colleagues in the Donnelly Centre for Cellular and Biomolecular Research.

“It feels amazing to receive the award,” says Abraham. “This is the culmination of years of work and, with [the support from CFI], Dragonfly can continue to expand our understanding of the universe for more years to come.

“Plus, the thing I love the most is that it sets up a really tremendous future for the students and post-docs working on the project.”

“The Dragonfly telescope has already made ground-breaking discoveries in its short life,” says Melanie Woodin, dean of the Faculty of Arts & Science. “It will be an even more remarkable instrument after the transformation made possible by the award. I’m very excited and congratulate Professor Abraham and the entire team.”

Roberto Abraham and the Dragonfly telescope (photo by Pieter van Dokkum)

Dragonfly currently comprises 48 commercially available telephoto lenses arranged in two arrays of 24 lenses – all aligned to point at the same target in the sky. The lenses feature special coatings that help make them effective for imaging at low-light levels.

The current array grew from smaller versions of three, eight and 10 lenses. With 48 lenses, Dragonfly performs like a telescope with a single lens measuring one meter in diameter, which would make it among the largest telescopes ever built.

The $1,819,000 CFI award will be used to purchase 120 additional lenses – as well as CCD cameras, filters and related hardware – for a total of 168 lenses.

Abraham, Dokkum and their collaborators have used Dragonfly to make many discoveries, including identifying an entirely new class of objects that they dubbed Ultra-Diffuse Galaxies. UDGs are comparable in size to the Milky Way Galaxy but contain a hundred to a thousand times fewer stars. They are perfect laboratories for studying dark matter, a form of matter we can’t see and that can only be studied because of its gravitational influence on ordinary matter like stars.

The upgraded Dragonfly will be able to better observe nearly invisible and incredibly diffuse hydrogen and helium gas-surrounding galaxies that are associated with dark matter.

“This is about more than just building a bigger telescope,” says Abraham. “What the team’s really excited about is the fact that the upgraded Dragonfly will be using highly specialized filters – made in Canada – to help us detect this gas.

“This material traces dark matter, which fuels the fire of star formation, so it’s the main agent responsible for the growth of galaxies. We know almost nothing about dark matter so the lure of the unknown is totally thrilling for our team.”

At U of T, that team includes PhD students Deborah Lokhorst and Colleen Gilhuly, and previously included U of T alumna Jielai Zhang, who is now a Schmidt Science Fellow at Oxford University.

“We feel like kids just starting out on a wonderful new adventure,” says Abraham. “Running out the back door with big dumb grins on our faces, greeting the new day with wonder as we see what the universe has in store for us. I can't wait.”