FTP, name the closest neighboring spiral galaxy.
Over one thousand years ago, the Persian Al-Sufi noted a "little cloud", but the  shape of the object was not properly identified until the nineteenth century. Named  for its proximity to a star itself named for a daughter of Cassiopeia, this entity was  the source of the first observed extrasolar supernova. Edwin Hubble located  Cepheid variables within this entity, thus proving it was not part of the Milky Way.  FTP, name the closest neighboring spiral galaxy.
Over one thousand years ago, the Persian Al-Sufi noted a "little cloud", but the  shape of the object was not properly identified until the nineteenth century.
Andromeda Galaxy