Wednesday, April 1, 2015

Incredible Explorations: Alumnus Discovers a First in Astronomy History

Dr. Sean Brittain has long had a penchant for new experiences. When he was 18, he ventured halfway across the country, from Virginia Beach to LeTourneau University, for the experience of being somewhere different. He decided to pursue astronomy during graduate school after receiving a  bachelor's in chemistry, a jump between relatively different fields. Now, he’s one of the first individuals in the world to observe and track the formation of a planet.

Brittain, a professor of astronomy and physics in Clemson University’s Department of Physics and Astronomy, graduated from LETU in 1997 with a degree in chemical physics. Then, in graduate school at the University of Notre Dame, he made what he refers to as “crazy shift” in areas of study.

He began working with faculty studying the organic chemistry of comets, which morphed into studying the chemistry of disks around young stars. The trajectory of his research did not, however, stop there.

“As projects do,” Brittain said, “our focus started to morph a bit, and my interest became in trying to answer the question: ‘how did the planets themselves form in these disks?’”

He and the Notre Dame faculty took their initial research and applied it to the theory that planets form from the disks around stars. Brittain explains that planets are formed by grain-like material that sticks together, eventually growing into a larger mass – like 'giant dust bunnies'.  

“If they get large enough, they collapse in under their own weight and start sweeping up gas out of the disk and start forming planets," he said. "That’s the idea, at least, but it hadn’t ever been observed before.”

Upon graduating from Notre Dame, Brittain was awarded the two-year postdoctoral Michaelson Fellowship – now called the Sagan Fellowship – with the National Optical Astronomy Observatory (NOAO). There, he continued his studies on disks of stars and monitored his observations long-term. 

NOAO's Gemini telescope
After years of ongoing research, Brittain and his team were given the chance to utilize NOAO’s Gemini telescope in Hawaii, which was no small feat in and of itself. NOAO telescopes are shared by multiple countries due to cost – typically $80-100 million to build one telescope. Not to mention, operation can cost up to six figures per night. In order to gain access to such a limited and sought after resource, research groups must submit proposals for approval to receive the opportunity to use it. Brittain was granted approval on multiple occasions.

Brittain explains how this led to a first in astronomy history, known as HD100546 – the first star to ever be observed forming into a planet:

“We made a hypothesis that this was a planetary-type orbit. By that point, the project had gone on for about a decade. We took our data and, sure enough, we had this gas that’s in a planetary orbit around the star. It turned out to be the size we expect for disks to be forming around planets. This is the first time we’ve been able to see a forming planet. The disk around it will eventually become its moon and, finally, it will be something more massive than Jupiter. It could be anywhere from five to 40 times the mass of Jupiter. It’s going to be a big thing.”

Brittain says this project took the ability to ask questions with confidence or, as he puts it, to “be curious and have that curiosity cultivated.” It’s a quality he says he gained as a student at LeTourneau and credits low student-to-teacher ratio.

“When you have small classes, you get a chance to interact with faculty, and the faculty get a chance to respond to you in a way they wouldn’t if you’re sitting in a lecture hall with 200 other people,” he said.

“I had lots of opportunities to do research early on at LeTourneau, so I came into grad school ready to do hands-on work. I took that with me when I went to Notre Dame, which prepared me to make the shift from chemistry as an undergrad to astrophysics as a PhD student. I had the confidence to do that. Even though I moved to a different area in my PhD program, the skill set that I gained at LeTourneau was extraordinarily valuable.”

Seeing the outcome of HD100546 would be phenomenal. The timeline, however, is currently estimated at one million years for it to become a full-fledged planet. For now, LETU is more than satisfied that one of its own accomplished such an incredible discovery.

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