  Observations show that star formation is an inefficient and slow process.
This result can be attributed to the injection of energy and momentum by stars
that prevents free-fall collapse of molecular clouds. The mechanism of this
stellar feedback is debated theoretically: possible sources of pressure include
the classical warm HII gas, the hot gas generated by shock-heating from stellar
winds and supernovae, direct radiation of stars, and the dust-processed
radiation field trapped inside the HII shell. In this paper, we measure
observationally the pressures associated with each component listed above
across the giant HII region 30 Doradus in the Large Magellanic Cloud. We
exploit high-resolution, multi-wavelengh images (radio, infrared, optical, and
X-ray) to map these pressures as a function of position. We find that radiation
pressure dominates within 75 pc of the central star cluster, R136, while the
HII gas pressure dominates at larger radii. By contrast, the dust-processed
radiation pressure and hot gas pressure are generally weak and not dynamically
important, although the hot gas pressure may have played a more significant
role at early times. Based on the low X-ray gas pressures, we demonstrate that
the hot gas is only partially confined and must be leaking out the HII shell.
Additionally, we consider the implications of a dominant radiation pressure on
the early dynamics of 30 Doradus.
