in fifth grade, Jeff Cooke devised an original theory of how the solar system formed. Bold as it was, his report did little to impress his Catholic-school teacher, whom he suspects frowned upon secular explanations for the heavens. Today, as an astronomer at the Swinburne University of Technology in Australia, Cooke continues to chart his own course. Last year he used a novel image-stacking method to discover a supernova more than twice as old as Earth. This technique has also allowed him to observe extremely ancient galaxies, charting the early evolution of the universe.
You’ve always been fascinated by astronomy, but in college at San Diego State University you nearly gave it up. Why? I was studying physics and working to pay my way through college. It was tough, and I decided to drop out and eventually started a sandwich shop. After a few years I had a long, hard look at myself and realized astronomy was what I wanted to do. I sold the store and went back to school.
When you returned to science, why did you decide to focus on the earliest days of the universe? I wanted to get to the bottom of everything. To do that, you’ve got to observe things at the farthest distances—which lets you look the farthest back in time.
How do you observe galaxies that are billions of light-years away?I stack together hundreds of deep images of the sky taken over years and years. That lets me see fainter, more distant objects.
One of the galaxies you studied is 11.4 billion light-years away. What does it tell us about the universe back then?
It’s the brightest known galaxy at that distance. When I first saw it, I called it Golden Boy. I was trying to figure out why it was so bright, and I realized there was more than one galaxy there. The galaxies were interacting, which triggers a lot of star formation and makes it brighter. The whole theory of how galaxies form is based on the idea that they start out small and then collide and merge together. We were able to see this process and confirm the theory.
Is it safe to assume that your astronomy reports are no longer ignored?
Yes, the Golden Boy galaxy got people very excited. But it’s still always a struggle in science to get a new idea accepted—and a great feeling when it is.