B.S. Astrophysics, 2013, Rice University
Office: 405 Nielsen Hall
I am interested in the behavior of M-dwarfs. M-dwarfs are expected to be the most common stars in our galaxy. They are very cool, very small, very dense stars, which makes them good candidates for planet searches. Because of their small radius and mass (relative to the Sun), the range around them in which Earth-like conditions could be found (their habitable zone) is much closer to the star than it is for Earth. As such, many observers are thoroughly studying their characteristics: evidence of circumstellar material, and the activity of the stars themselves. Many M-dwarfs give off powerful flares, in which the stars become multiple times brighter than their normal, quiescent state. These flares, similar to solar flares but often much stronger, would have a definite impact on how life might form around these stars. I am currently studying the behavior of M-dwarfs from two different angles.
In collaboration with researchers at NASA's Goddard Space Flight Center and Adler Planetarium, I am one of the researchers on the Disk Detective project. Disk Detective uses full-sky survey data (from the Digital Sky Survey, the Sloan Digital Sky Survey, the 2-Micron All-Sky Survey, and the Wide-Field Infrared Survey Explorer) to find debris disks around stars. These disks, causing excess radiation in the infrared, are thought to be leftover material from the formation of planetary systems around stars, similar to our Kuiper belt. We also see hot debris disks, thought to be similar to belts of dust in our asteroid belt. WISE likely found over a thousand previously-unobserved debris disks, but finding them all requires visual inspection of the data, and follow-up observation. As such, the Disk Detective Web site allows users to classify possible targets, helping us eliminate the obviously poor candidates. DiskDetective.org launched in late January 2014, and is (as of this writing) approaching its one-millionth user classification.
I am also studying the flare behavior of the M-dwarf GJ 1243, in collaboration with researchers at the University of Washington. GJ 1243 is the most active M-dwarf in the field of view of the Kepler mission, which searches for planets by taking high-cadence (one-image-per-minute) images of stars of interest and monitoring for changes in brightness. Because of Kepler's high-cadence capabilities, GJ 1243 is uniquely positioned to give us unprecedented insight into the behavior and morphology of flares on M-dwarfs.
"Kepler Flares IV: A Comprehensive Analysis of the Activity of GJ 1243," Silverberg, S., Kowalski, A., Davenport, J., Wisniewski, J., Hawley, S., & Hilton, E., AJ, in press, (2016)
In Research Group
John Wisniewski, Presidential Professor, Assistant Professor