How can star formation be sustained?

  title={How can star formation be sustained?},
  author={Filippo Fraternali},
  journal={Proceedings of the International Astronomical Union},
  pages={228 - 239}
  • F. Fraternali
  • Published 1 May 2013
  • Physics
  • Proceedings of the International Astronomical Union
Abstract There is overwhelming evidence that the Milky Way has formed its stars at a relatively constant rate throughout the Hubble time. This implies that its stock of cold gas was not in place since the beginning but it has been acquired slowly through gas accretion. The gas accretion must have been at low metallicity in order to reconcile the metallicities observed in the disc with the predictions of chemical evolution models. But how does this gas accretion take place? I review the current… 

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