Spitzer Space Telescope - Directors Discretionary Time Proposal #227


Taking the Temperature of the New Planet TrES-1

Principal Investigator: David Charbonneau
           Institution: Harvard

Co-Investigators: 
Lori Allen, Harvard-Smithsonian CfA                                   
Timothy Brown, High Altitude Obs. NCAR                                
Ronald Gilliland, STScI                                               
David Latham, Harvard-Smithsonian CfA                                 
Georgi Mandushev, Lowell Obs.                                         
Tom Megeath, Harvard-Smithsonian CfA                                  
Guillermo Torres, Harvard-Smithsonian CfA                             
Roi Alonso Sobrino, Instituto de Astrofisica de Canarias              
Francis O'Donovan, Caltech                                            
Alessandro Sozzetti, Harvard-Smithsonian CfA                          

Science Category: extrasolar planets 
 Observing Modes: IracMap 
  Hours Approved: 6.0 

Abstract:
We propose to observe the newly-discovered transiting planet TrES-1
during the time of secondary eclipse (when the planet passes behind
the star).  A successful measurement of this eclipse would constitute
the first direct detection of emission from an extrasolar planet.  The
secondary eclipse will reveal two key quantities of the planet:  its
temperature (from the eclipse depth), and its orbital eccentricity
(from the eclipse timing).  Moreover, these observations will enable
us to characterize the high-precision, rapid-cadence photometric
performance of IRAC.  A successful demonstration of this innovative
use of IRAC would open a new observing mode for Spitzer with
applications extending well beyond the study of extrasolar planets.