Abstract. The Herschel Space Observatory has been revolutionizing our understanding of the the earliest phases of star formation. In this contribution, we describe early results from the Gould Belt Survey, a Herschel Key Project to map 15 nearby molecular clouds in continuum emission from 70 μm to 500 μm. In particular, I describe how the sensitive and wide maps of the Aquila Rift have strongly confirmed the similarity between the shapes of the stellar Initial Mass Function and the prestellar core mass function (CMF). Also, the Herschel map sensitivity to larger scale emission has revealed that prestellar cores form almost exclusively within dense filaments that exceed a critical mass per unit length defined by temperature (and gravity). Finally, filaments in three clouds, IC 5146, Polaris and Aquila, are found to have similar widths of ∼0.1 pc, approximately the scale where the turbulent velocity equals the sound speed of 10 K gas. This common width suggests filaments themselves are formed through collisional shocks of turbulent flows and evolve in quasi-virial balance through mass accretion.

Key words:far-infrared/submillimetre -- prestellar cores -- Herschel Space Observatory