Explanation:
While most spiral galaxies, including our
own Milky Way,
have two or more spiral arms, peculiar
galaxy
NGC 4725 has only one.
In this
false-color Spitzer Space Telescope
infrared
image, the galaxy's solo spira mirabilis
is seen in red, highlighting
the emission from dust clouds warmed by newborn stars.
The blue color is light from NGC 4725's population
of old stars.
Also sporting a prominent ring and a central bar, this
galaxy is over 100 thousand light-years across and lies 41 million
light-years away in the well-groomed constellation
Coma Berenices.
Computer
simulations
of the formation of single spiral
arms suggest that they can be either leading or trailing
arms with respect to a galaxy's
overall rotation.
Watch: Bright Planets at Sunset
