  Stephan's Quintet (SQ) is a compact group of galaxies that has been well
studied since its discovery in 1877 but is mysterious using cold dark matter
hierarchical clustering cosmology (CDMHCC). Anomalous red shifts $z =
(0.0027,0.019, 0.022, 0.022, 0.022)$ among galaxies in SQ either reduce it to a
Trio with two highly improbable intruders from CDMHCC or support the Arp (1973)
hypothesis that its red shifts are intrinsic. An alternative is provided by the
Gibson 1996-2006 hydro-gravitational-dynamics (HGD) theory where superclusters,
clusters and galaxies all originate by gravitational fragmentation in the
super-viscous plasma epoch and at planetary and star cluster mass scales in the
primordial gas of the expanding universe. By this fluid-mechanical cosmology,
the SQ galaxies gently separate and remain precisely along a line of sight
because of perspective and the small transverse velocities permitted by their
sticky viscous-gravitational beginnings. Star and gas bridges and
young-globular-star-cluster (YGC) trails observed by the Hubble Space Telescope
are triggered as SQ galaxies separate through viscous baryonic-dark-matter
halos of dark proto-globular-cluster (PGC) clumps of frozen Earth-mass
primordial-fog-particles (PFPs).
