Poetic Physics: Measuring Stars By Their Internal Music

Asteroseismology is letting us measure distant planetary systems with sunlike stars. How? By measuring the way a star "breathes" in response to its on internal music. Find out how physics takes another run at getting its master's degree in poetry.

A mysterious star system was recently discovered. Usually, solar systems consist of rocky planets hugging close to their central star, and huge gas giants orbiting far away. Kepler has these two types orbiting right next to each other. At their closest, the gas giant and the rocky Earth-like planet are separated by a distance a little less than five times the distance from the Earth to the Moon. The above image is what the gas giant rising in the sky would look like from the point of view of someone sitting on the rocky planet.

But how did they find them all in the first place? Asteroseismology is a little different from the geoseismology we often see on the news. Instead of examining occasional, fitful tremors, sun-like stars have a deep resonance. The internal sound waves of the star are trapped inside, moving back and forth. Eventually they achieve a specific vibration, the way a musical note resonates in a tuning fork. This vibration causes the outside of the star to pulse, gently, like it's breathing. The deeper the resonance, the larger the star. By tracking this resonance, researchers are able to find its size, and from there, they're able to track its light and motion to detect planets.

Apparently, listening to the music of the spheres is now a valid scientific technique.

Image: David A. Aguilar (CfA)

Via Science Express.