Spitzer Space Telescope - General Observer Proposal #50134


The Local Group Dwarf Spheroidals

Principal Investigator: Pauline Barmby
           Institution: SAO

     Technical Contact: Pauline Barmby, SAO

Co-Investigators: 
Joseph Hora, SAO                                                      
Karl Gordon, STScI                                                    
Tom Jarrett, SSC                                                      
Matthew Ashby, SAO                                                    

Science Category: local group galaxies 
 Observing Modes: IracMap MipsPhot MipsScan 
  Hours Approved: 30 

Abstract:
We propose to complete the Spitzer survey of the Local Group. The galaxies not
yet observed include most of the dwarf spheroidals, a galaxy type which,
although numerous, has not been heavily studied by Spitzer so far. Imaging
observations with IRAC and MIPS will yield a complete census of asymptotic giant
branch stars, probing mass loss in galaxies with a range of metallicities,
masses, and environments. Long-wavelength MIPS observations will detect any
insterstellar dust or constrain the gas-to-dust ratio. Completing the Spitzer
observations of Local Group galaxies forms an important part of the Spitzer
Legacy for future missions.