Penn State Students Blow Bubbles in the Milky Way
Our galaxy literally is bursting with newly forming stars, too many for astronomers to count. So they're enlisting outside help: you. Now non-astronomers can go online and log onto the Milky Way Project, a website designed for the public with the help of Matthew Povich, a postdoctoral fellow at Penn State University, and the students in his Fall 2010 Astronomical Universe course.
Bubbles blown by newly formed stars float in the Milky Way. Photo credit: NASA/JPL-Caltech/M. Povich (Penn State)
At the Milky Way Project, the public can see beautiful infrared images of our galaxy taken by the Spitzer Space Telescope. Bubbles, a sign of star formation, float amidst the stars in almost every picture. But the public can do more than just look. By pointing out bubbles and other interesting objects, "citizen scientists" can help astronomers unravel the mysteries of star formation.
Before they released the images to the public, Povich and his collaborators wanted to be sure that the site was ready for general use. That was where Povich's Astronomical Universe class came in.
"We were the guinea pigs because we used the website for a class project before it was launched to the public," said Samantha Krone, a sophomore majoring in management and Spanish. "It was cool to be a part of that."
While the students were testing out the website's interface, they also were learning about star formation.
"The purpose of the class project was to simulate actual research, where the answer is not known, the questions are of real interest to astronomers, and the data are real and not canned," Povich said.
The students found and drew bubbles, such as the one in the image above, using a bubble-drawing tool. Inside the bubbles, newly formed stars heat dust until it glows red in the false-color infrared image. Organic molecules at the edge of the bubble shine in green.
The Milky Way Project's full database contains 12,000 images, and each student looked through 50 images. So why not use a computer to do the same thing?
Richard Kripplebauer, a senior majoring in English, draws bubbles on the Milky Way Project. Photo Credit: M. Povich
"I think the best analogy is that we were doing facial recognition for these star-formation regions," said Richard Kripplebauer, a senior majoring in English and an ROTC cadet. "The human mind can do easily what a computer can't -- look at an image and realize that it's in three dimensions. So humans can still tell it's a bubble even if it's skewed one way or the other."
Not only are humans better at pattern recognition, but there is also power in their numbers.
"Some of the students fretted about whether they were doing this right," Povich said. "The beauty of something like the Milky Way Project is that it doesn't matter because we're relying on measurements made by thousands of people instead of just one person. As long as the students did their best, they were doing it right."
After drawing and cataloging bubbles, Povich's class completed calculations to learn about the rate of star formation in the Milky Way -- the ultimate goal of astronomers, too.
"At the end of the assignment, the students found 10 times more bubbles than have been found by all the previous studies done by trained astronomers," Povich said. "We realized immediately that the Milky Way Project is worth doing. We're going to find a lot more bubbles than before."
The project proved as meaningful to the students as to the scientists.
"It was a humbling experience," Kripplebauer added. "When you look at a star-formation region, and see another behind it, and another behind that, you get a better perspective of where you are in the universe."