NGC 5634 -- Globular Cluster in Virgo
What is a Globular Cluster doing in Virgo?
The constellation of the Virgin (Virgo) is home to and famous for its galaxies. If you want
galaxies, then Virgo is your place. If you want globular clusters then search the skies around
our galactic center (Sagittarius, Scorpius, Ophiuchus, etc.). There are exceptions, and the
Globular Cluster, NGC 5634, in Virgo is the perfect example. A lone globular cluster among
Its odd location is because it did not originate in our Milky Way Galaxy. Its birthplace was the
Sagittarius Dwarf Spheroidal Galaxy. This smaller galaxy is currently in the process of being
ripped apart by the much larger Milky Way Galaxy. NGC 5634 was torn from its home galaxy
and is being thrown through our own galaxy. Currently, it is in Virgo.
NGC 5634 was easy to see from my suburban backyard with the 155mm refractor. None of
the hundreds-of-thousands of its stars were bright enough to see individually, but their
combined light formed a spherical glow that was easily picked up in the eyepiece.
The three stars that were visible within the spherical glow are stars located between Earth and
the globular cluster and are not part of the cluster proper. The brightest of the three, located
1.3 arcminutes from the center of the cluster, is the orange-giant star (HD 127119). Its
distinctive orange color (K2 – spectral class) stood out. HD 127119 is only 2,000 light years
from Earth, far closer than the globular cluster at 82,200 light years. The orange star was a
nice touch to the overall view of the cluster.