Past Winner
Bourse commémorative E.W.R. Steacie de 2005

Roberto Garcia Abraham

Astrophysics

University of Toronto

Roberto Garcia Abraham

After years of studying distant galaxies with the Hubble Space Telescope, Dr. Roberto Abraham, one of six winners of the 2005 NSERC E.W.R. Steacie Memorial Fellowship, has his sights set on an image no one has ever seen: the birth of our Universe's first galaxies.

Big Idea: "Progress in cosmology is completely driven by observations right now. It's the wild frontier of science," says University of Toronto observational astrophysicist Dr. Roberto Abraham. "Getting the right sort of data is often incredibly hard, but once you have it, then it’s sometimes the case that in two seconds you realize that the Universe just doesn't work quite the way you thought it did."

The Question: What's the origin of galaxies and how do they evolve? These are key questions in cosmology, because galaxies are where all of the action takes place – the turbulent birth and death of stars, and thus the creation of all of the chemical elements that make up our world. In the 1920s, renowned U.S. astronomer Edwin Hubble set the framework for the 20th century understanding of the evolution of galaxies. He categorized the then observable galaxies (relatively nearby galaxies, cosmically speaking, typically only a few tens of millions of light years away) into two broad groups: elliptical and spiral. In the late 1990s, however, work by Dr. Abraham using groundbreaking images, ironically from the Hubble Space Telescope, showed that many of the most distant galaxies didn't fit the Hubble classification system. Today more than half of the most distant galaxies observed by the Hubble Space Telescope are simply classified as "peculiar." It's an odd situation indeed, says Dr. Abraham, one he'd like to rectify. "We're groping for a galaxy classification system that will let us say something meaningful about galaxies at a range of ages, and especially about those we see in the really distant Universe," he says.

Research at the Edge: When he was 12 years old, Roberto Abraham looked through a telescope for the first time. He was at his family cottage and the moon, Earth's closest celestial neighbour, filled his viewfinder. In 2004, Dr. Abraham used Canada’s newest major resource for astronomy, the massive Gemini Telescope in Hawaii, to capture images of the most distant massive galaxies ever seen. Rather than looking back in time 1.3 seconds (about the time it takes light to travel from the moon to Earth) he was peering back 10.3 billion years, more than five billion years before the formation of our Sun. The initial results of this long-range view, an international collaboration dubbed the Gemini Deep Deep Survey (GDDS), shook the foundations of galactic formation theory. Rather than observing a bevy of smaller galaxies, the GDDS saw an early Universe already populated with large galaxies previously assumed to form only through the collision of smaller ones. "What we found was the exact opposite of what we were expecting," notes Dr. Abraham. The survey relied on a radical new telescope technique, called the "nod and shuffle," which Dr. Abraham’s team brought to the telescope by partnering with scientists at Canada's Herzberg Institute for Astrophysics. Using this technique the massive 350-tonne Gemini telescope was gently rocked with exquisite precision in order to cancel out atmospheric variations and thus provide a stellar view of the deep, deep cosmos.

The Next Step: "With the time provided by the NSERC Steacie Fellowship I'd like to go back even further, to about 300 to 400 million years following the Big Bang. The goal is to see the very first generation of galaxies forming before our eyes," says Dr. Abraham. To achieve this, he's once again relying on a combination of a powerful telescope and its innovative use. Dr. Abraham is developing a tuneable filter technique that will enable his team to use the new laser adaptive optics system on the Gemini telescope to focus on the faint infra-red light that astrophysicists believe was emitted at the birth of the first galaxies. At the same time he'll also be using a mathematical model he's developed to continue to quantify the classification of galaxies. The model relies on the use of an optical image recognition system to rapidly classify thousands of objects. The hope is to replace the Hubble galaxy classification system with one that helps tell the story of galactic evolution from first light to the present.