NGC 5253
This remarkable starburst dwarf galaxy, 2.8 Mpc away, is the site of
the youngest starburst known. This is the Halpha image from the Hubble
Space Telescope. The black blob in the center is where an intense radio
and infrared source has been blacked out. We consider this
source to be a super-star-cluster and the very youngest globular cluster--only
about a million years old--that has ever been observed. The starburst in
this galaxy may have been started by the accretion of a small cloud of
gas from inter-galactic space.