Spitzer Discovery of Very Low Luminosity Objects
  The Spitzer Space Telescope allows for the first time to search systematically for very low luminosity (= 0.1 L_sun) objects (VeLLOs) associated with dense molecular cores. They may be the first candidate Class 0 sources with sub-stellar masses. We describe such a source in the dense molecular core L1148. VeLLO natal cores show properties that are unusual for star-forming cores. The low luminosity and in some cases the lack of prominent outflow could be the result of the small gas supply near the VeLLO. 
Jens Kauffmann (1), Frank Bertoldi (2), Neal.J. Evans II (3) and the   c2d Collaboration ((1) Max-Planck-Institut fuer Radio...