Explanation:
While most spiral galaxies, including our
own Milky Way,
have two or more spiral arms, NGC 4725 seems to have only one.
In this sharp color image,
the solo spira mirabilis
is tightly wound, traced by bluish, newborn star clusters.
The odd galaxy also sports obscuring
dust lanes, a prominent ring, and a yellowish central bar structure
composed of an older population of stars.
NGC 4725 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.
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