Searching for Sun-like stars with satellites and supercomputers

Travis Metcalfe, NCAR's High Altitude Observatory

Photograph of Travis Metcalfe
Travis Metcalfe (©UCAR. Photo by Carlye Calvin.)


Travis Metcalfe is now a research scientist at the Space Science Institute in Boulder, Colorado. (May 2012)

There is no mistaking Travis Metcalfe’s enthusiasm for astronomy. His eyes light up, he breaks into a broad smile and simply says, "I’m working in my dream job."

An asteroseismologist in NCAR’s High Altitude Observatory, Travis studies stars similar to the Sun in order to understand in what ways our Sun is peculiar.

"I like to tell people, imagine if an extraterrestrial came to Earth and interviewed one person in great detail. Depending on who that person was, they might get a pretty biased view of the human race." The same applies when it comes to studying the Sun, explains Travis. Scientists need to study stars like the Sun to understand what is typical and what is unique.

Stars reveal clues to their internal structures through oscillations, or "starquakes," he continues. When this seismic activity ripples to the surface, scientists "read" it as changes in light intensity. "These variations in brightness give us all kinds of information," including the star’s age, radius, composition, temperature, rotation speed, and magnetic activity.

Travis describes his use of "genetic algorithms" to analyze data from the Kepler mission in this Google Tech Talk (January 13, 2009).

New eyes in space

Much of Travis' work over the past few years has been gearing up for NASA's Kepler satellite mission. Designed to find habitable planets, Kepler's space telescope will search our region of the galaxy for Earth-like planets in orbit around Sun-like stars.

 "A big question is, how common are planets like Earth around other stars like the Sun? Are we unique, rare, or typical in that regard? In four years we will have the answer, which is pretty exciting."

Travis will examine the characteristics of the stars that these yet-to-be discovered planets, are orbiting. Kepler's powerful telescope will provide the opportunity to observe thousands of stars over the lifetime of the mission.

In October 2009, Kepler will start providing large installments of data every three months until at least 2013. Travis has spent several years developing a computational method for NCAR's Blue Gene supercomputer to process and analyze the vast quantities of data Kepler will transmit. He will work with scientists around the world comparing the observations with computer model simulations.

Photograph of space with superimposed lines and words
The field of view for NASA's Kepler space telescope, superimposed on a photo of the Cygnus regon of the Milky Way. Launched March 6, 2009, with a mission to hunt for Earth-like worlds, the telescope began testing soon after and takes up the hunt in earnest in October. [ENLARGE] (Photo by Carter Roberts, illustration courtesy NASA Kepler Mission.)

Beginning with a backyard telescope

Travis credits a second grade teacher with first capturing his imagination about the stars. "She would mention things like a lunar eclipse, or 'you can see Jupiter tonight.' "

"As a kid in junior high I was focused on looking at the stars with telescopes. I had a small one in the backyard. I would wonder if there are other people out there like me looking back at Earth wondering the same thing: Where do I fit in?"

In high school Travis learned some practical applications of astronomy by doing research and quantitative problem solving, like measuring the height of mountains on the moon.

Travis grew up in rural Oregon, a few blocks from the ocean in a small town with a population of less than 10,000. "There were not too many lights to get in the way of viewing the night time sky, although all the ocean moisture in the air isn't great for seeing the stars. That's why I went to college in Arizona, it's the driest place I could find!"

He went on for his Ph.D. in astronomy at the University of Texas at Austin. Travis was a postdoctoral fellow at Aarhus University in Denmark and Harvard-Smithsonian Center for Astrophysics before coming to NCAR five years ago.

In grad school Travis was exposed to a number of career options but says it was the research that got him excited, so he followed that track. "I'm also interested in education outside of the classroom, writing science pages for Windows to the Universe and demystifying some of the science reported in the news through my Starstuff blog."

Taking the long view

Travis describes himself as a "patient optimist" doing exactly what he loves.

 "I've always had a desire to contribute something important to society, even though the science I do is one small piece of a big puzzle. Contributing in some way to our understanding of things like climate change is important to me." And patience is almost a requirement in his discipline. "You've got to have a long view in this field because it takes a long time to get an answer, or even part of an answer. It's worth the wait."

Related Links

Travis Metcalfe's home page

by Rachael Drummond
June 2009