Fast molecular outflow from a dusty star-forming galaxy in the early Universe

See allHide authors and affiliations

Science  07 Sep 2018:
Vol. 361, Issue 6406, pp. 1016-1019
DOI: 10.1126/science.aap8900

You are currently viewing the abstract.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

Molecular gas ejected from a distant galaxy

Galaxies grow by forming stars from cold molecular gas. The rate at which they do so is limited by various feedback processes (such as supernovae or stellar winds) that heat and/or eject gas from the host galaxy. Spilker et al. used submillimeter observations to discover an outflow of molecular gas from a galaxy in the early Universe, a period of vigorous star formation. Modeling the outflow revealed that the mass of gas being ejected is similar to that being turned into stars. The results will help determine how quickly galaxies formed after the Big Bang.

Science, this issue p. 1016


Galaxies grow inefficiently, with only a small percentage of the available gas converted into stars each free-fall time. Feedback processes, such as outflowing winds driven by radiation pressure, supernovae, or supermassive black hole accretion, can act to halt star formation if they heat or expel the gas supply. We report a molecular outflow launched from a dust-rich star-forming galaxy at redshift 5.3, 1 billion years after the Big Bang. The outflow reaches velocities up to 800 kilometers per second relative to the galaxy, is resolved into multiple clumps, and carries mass at a rate within a factor of 2 of the star formation rate. Our results show that molecular outflows can remove a large fraction of the gas available for star formation from galaxies at high redshift.

View Full Text