JPL Home NASA Home Caltech Home
Follow this link to skip to the main content
NASA Logo - Jet Propulsion Laboratory   + View the NASA Portal
Search JPL
JPL Home Earth Solar System Stars & Galaxies Technology
Science Visitor and Colloquium Program
SVCP Home
Meetings
Information for Visitors
Contact
Restricted
 
Astrophysics Colloquium

Hubble's Ultraviolet View of Protoplanetary Disks and Exoplanetary Environments
Presented by Kevin France
Department of Astrophysical and Planetary Science, University of Colorado

Friday, March 13, 2015
12:00 noon in 169-336

Abstract
The composition and spatial distribution of molecular gas in the inner few AU of young (< 10 Myr) circumstellar disks are important components to our understanding of the formation of planetary systems. In the first part of this talk, I will discuss the current, observationally-based picture of protoplanetary gas disks at r < 10 AU, reviewing the most widely used spectral diagnostics of the inner disk, and highlight recent observations of H2 and CO made by the Hubble Space Telescope. I will describe how molecular spectroscopy is being used to constrain the distribution of gas in the inner disk at spatial scales too small to resolve with current imaging instruments/facilities.

In the second part of this talk, I will discuss how the spectral and temporal behavior of exoplanet host stars is a critical input to models of the chemistry and evolution of planetary atmospheres. I will present results from a panchromatic (Hubble/Chandra/XMM/optical) Hubble Treasury program that is currently underway to characterize the energetic radiation environments around low-mass host stars for the first time. We find that all exoplanet host stars observed to date exhibit some level of UV/X-ray activity, and that strong flares and stochastic variability are common, even on "optically inactive" M dwarfs hosting planetary systems. I will briefly discuss the use of these data in atmospheric models of rocky planets around cool stars, including the predicted abiotic production of O2 and O3 - a cautionary tale for the interpretation of "biomarker" gases when they are detected in the coming decades.

JPL Contact: Paul Johnson (3-4749)


SVCP Astrophysics


Privacy / Copyrights
  NASA Home Page
Site Manager:
Webmaster:

CL 08-3220