Most stars are born surrounded by disks of gas and dust, and it is in these disks that planets form. However, the gas and dust that makes up these disks (Fig. 1) does not all go into forming planets. Indeed, much of the disk material slowly falls, or accretes, onto the newly formed star, setting its final mass. For many years, astronomers have studied such accretion disks and measured the rate at which the material accretes onto young stars, but exactly why such accretion occurs so efficiently has remained elusive. Over the past several years, researchers have started to zero in on a solution in theoretical studies for the evolution of an accretion disk that involves the action of magnetic fields. Unfortunately, until just this year there were no observations of the required magnetic fields in the disks. On page 597 of this issue, Stephens et al. report how they have now clearly detected magnetic fields in one such disk.
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