An actively accreting massive black hole in the dwarf starburst galaxy
  Henize 2-10
  Supermassive black holes are now thought to lie at the heart of every giant
galaxy with a spheroidal component, including our own Milky Way. The birth and
growth of the first 'seed' black holes in the earlier Universe, however, is
observationally unconstrained and we are only beginning to piece together a
scenario for their subsequent evolution. Here we report that the nearby dwarf
starburst galaxy Henize 2-10 contains a compact radio source at the dynamical
centre of the galaxy that is spatially coincident with a hard X-ray source.
From these observations, we conclude that Henize 2-10 harbours an actively
accreting central black hole with a mass of approximately one million solar
masses. This nearby dwarf galaxy, simultaneoulsy hosting a massive black hole
and an extreme burst of star formation, is analogous in many ways to galaxies
in the infant Universe during the early stages of black-hole growth and galaxy
mass assembly. Our results confirm that nearby star-forming dwarf galaxies can
indeed form massive black holes, and that by implication so can their
primordial counterparts. Moreover, the lack of a substantial spheroidal
component in Henize 2-10 indicates that supermassive black-hole growth may
precede the build-up of galaxy spheroids.
