Deep Space Dust Busters

A USF astrophysics team sweeps away intergalactic "fog"

By ARVIN TEMKAR, USF NEWS Posted Wed, 06/07/2017 - 16:28

A USF astrophysics team’s research into space dust paves the way for scientists to better understand how the universe evolves. 

Professor Xiaosheng Huang and students Zachary Raha ’16 and Andrew Stocker ’15, along with a scientist at Lawrence Berkeley National Laboratory, came up with an innovative computer model that accounts for interference caused by interstellar dust surrounding a faraway supernova, or exploding star.

Scientists use supernovae brightness to measure great distances in space. Dust can obscure supernovae light — similar to the way fog dims an oncoming headlight. The USF team’s model effectively wipes away the fog, allowing the team to more accurately measure the distance from our Milky Way galaxy to the supernova’s galaxy.

A first for science

“It’s the first time scientists have applied this kind of computer algorithm to supernova spectra to eliminate interference from dust, in order to better measure distances,” says Huang, who teaches physics and astronomy.

Being able to more accurately measure great distances in space is key to helping scientists understand why the universe is expanding at an accelerated rate, and how the universe has evolved since the Big Bang, Huang says.

The USF team’s work was published earlier this year in The Astrophysical Journal, the field’s premier academic journal.

Huang, leader of the project, was first author on the research paper, which drew on supernovae data collected by an international group of scientists. Raha, who worked with Huang for three summers, was credited as second author — a prestigious distinction for an undergraduate.

“It was rewarding to see the two students grow,” Huang said. “And they helped me clarify my thinking. They asked good questions.”

Learning from a Nobel laureate

For Raha, who majored in physics, the research was an introduction to the world outside the classroom.

“In school you get used to textbooks, where you’re able to extract information because it’s easily laid out for you,” says Raha. “But we were reading technical research papers. It’s different because scholars are usually only writing for members of their own community, so it takes  little bit more getting used to.”

After graduation Raha completed an internship at Lawrence Berkeley National Laboratory, working with Nobel laureate physicist Saul Perlmutter on another supernovae research project.

“After my internship I’ve become a lot more sure that astrophysics research is a career I want to pursue,” he says. “I’m hoping to apply for graduate school next. I’m really excited about having this career where I can basically learn for a living.”

Stocker, a math major who worked on the project for one summer before graduating, is completing a doctorate in math at the University of Colorado Boulder.

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