LPL Colloquium:

Tuesday, Feb 19, 2013
3:45 pm
Location: Kuiper Space Sciences
Room: 308

Dr. Travis Barman
Assistant Astronomer
Lowell Observatory

Host: Caitlin Griffith

Direct Imaging and Spectroscopy of Extrasolar Planets


Gas giants in wide orbits (> 5 AU) have now been directly imaged around young nearby stars. This, however, is just the beginning. New instruments, tailor made for high-contrast imaging, are coming online this year and will reveal dozens of young planets. These instruments will also provide low resolution near-IR spectra of each new planet, revealing a wealth of information across a wide range of planet masses and ages. To illustrate the great potential of direct imaging, this talk will focus on recent near- infrared photometry and spectroscopy of the planets orbiting the young (~ 30 Myr) star HR8799. Ground-based observations have allowed the characterization of the planets' bulk properties along with their atmospheric structure. New spectroscopic data of HR8799c will be presented that contain numerous, well-resolved, molecular lines. These data reveal the chemical composition of the planet's atmosphere
(in particular the carbon and oxygen abundances) and may help distinguish between core-accretion and gravitational instability as the most likely formation mechanism.