Yale Astronomers Eager for Kepler Spacecraft Data
When NASA’s Kepler spacecraft blasts into space on March 6, thousands of scientists around the globe will get one step closer to finding out just how unique Earth — and possibly life — really is.
The robotic probe will spend the next three-and-a-half years analyzing stars within our Milky Way galaxy in the hopes of discovering Earth-like planets - those that could contain liquid water and therefore support life.
But among the thousands of eager “ET” hunters will be a smaller group of scientists interested not in the search for Earth-like planets, but in the host stars themselves.
Yale astronomer Sarbani Basu is one of them. For most of her career, she’s studied stars, trying to come up with models that describe their behavior and structure. To do this, she analyzes stars’ seismology. Just as seismologists on Earth can learn about the planet’s internal structure through earthquakes, Basu is able to discover information about a star’s inner structure by studying “starquakes.”
Although stars appear to the average observer to be steadfast infernos in the night sky, they’re actually quite dynamic, notes Basu. Our own sun expels the same amount of energy as nine trillion atomic bombs every second. The sun also pulsates, and it’s these pulsations that give Basu clues as to what’s happening throughout the different layers of the star — from its outer photosphere, or visible surface, right down to its core.
“We actually know more about the core of our Sun than we do about the core of the Earth,” Basu says. This is because the sun’s tremors propagate in a more straightforward fashion through its gaseous layers than do the Earth’s, which is solid. Not surprisingly, she adds, astronomers also know much more about the sun than they do about more distant stars.
The Kepler mission, although designed primarily to look for planets, will give stellar astronomers the chance to study a vastly greater number of stars - 100,000, to be exact - than they ever could before. Basu and her team will use the data to test their models about how stars work, including things like how much helium and other elements they contain, how they evolve and how old they are.
Kepler will image some of the 100,000 stars every minute, and others every 30 minutes, depending on how quickly they pulsate. The first batch of scientific data, arriving in October, will keep both Basu as well as several of her graduate students busy for a long time to come, notes the Yale astronomer.
“I’m hoping for some big surprises,” Basu says. “If we find that all our models are perfect, that would be really boring.”
— By Suzanne Taylor Muzzin