  Feedback from massive stars plays a critical role in the evolution of the
Universe by driving powerful outflows from galaxies that enrich the
intergalactic medium and regulate star formation. An important source of
outflows may be the most numerous galaxies in the Universe: dwarf galaxies.
With small gravitational potential wells, these galaxies easily lose their
star-forming material in the presence of intense stellar feedback. Here, we
show that the nearby dwarf galaxy, the Small Magellanic Cloud (SMC), has atomic
hydrogen outflows extending at least 2 kiloparsecs (kpc) from the star-forming
bar of the galaxy. The outflows are cold, $T<400~{\rm K}$, and may have formed
during a period of active star formation $25 - 60$ million years (Myr) ago. The
total mass of atomic gas in the outflow is $\sim 10^7$ solar masses, ${\rm
M_{\odot}}$, or $\sim 3$% of the total atomic gas of the galaxy. The inferred
mass flux in atomic gas alone, $\dot{M}_{HI}\sim 0.2 - 1.0~{\rm
M_{\odot}~yr^{-1}}$, is up to an order of magnitude greater than the star
formation rate. We suggest that most of the observed outflow will be stripped
from the SMC through its interaction with its companion, the Large Magellanic
Cloud (LMC), and the Milky Way, feeding the Magellanic Stream of hydrogen
encircling the Milky Way.
