A Quintet of Galaxies
Credit:
Five closely grouped galaxies are visible in this image
made using the
Kitt Peak National Observatory 2.1 meter telescope.
The grouping is commonly known as
Stephan's Quintet.
Four of the galaxies show essentially the same
redshift suggesting
that they are at the same distance from us.
The large bluish spiral below and left of center actually has
a smaller redshift than the others, indicating it is much closer.
It is probably a foreground object which happens to lie
along the line of sight to the more
distant galaxies.
Of the four distant galaxies, three seem to be colliding, showing serious
distortions due to gravitational tidal forces.
The fourth is a normal appearing elliptical galaxy (at the lower
right edge of the field).
Recent results suggest that collisions play an important
role in the life cycles of galaxies.