The Caldwell Objects

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NGC 5005
Type: Mixed Spiral Galaxy
(SABbc)
Con: Canes Venatici
RA: 13 h 10.9 m
Dec: +37° 03'
Mag: 9.8
Dim: 5.6' X 2.9'
SB: 12.7
Dist: 69 million light-years
Disc: William Herschel, 1785
W. HERSCHEL: [Observed 1 May 1785] Very
bright. Considerably large, much
extended from south pre-
ceding to north following [from southwest to northeast].
Suddenly much brighter in the middle. 6' long. 1½’
broad. (H I-96)
GC: Very bright, very large, very much extended toward
position angle 25°, very suddenly brighter in
M OST GALAXIES TRAVEL THE DEPTHS OF
space gravitationally bound to other galaxies.
NGC 5005 belongs to a group of 29 moderately
distant galaxies that R. Brent Tully (University of
Hawaii) and J. Richard Fisher (National Radio
Astronomy Observatory) call the Canes Venatici
Spur. It is a relatively large spiral with a diameter
of 100,000 light-years (about that of our Milky
Way) and a luminosity of 50 billion Suns. From
our vantage point we see NGC 5005 inclined 36°
from edge on. This offers us a good view of its
intriguing spiral structure.
NGC 5005 is a late-type spiral whose visual
appearance hints at the presence of a central bar.
Photographs taken with large telescopes reveal
an extremely sharp nucleus nestled in a bright
lens-shaped core. Outside the core the spiral
arms are moderately tight, with many
The Caldwell Objects
the middle to a nucleus.
NGC: Very bright, very large, very much extended toward
position angle 66°, very suddenly brighter in the middle to a
nucleus.
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knots and dark lanes. One prominent and peculiar
dust lane in the galaxy's southwestern quadrant
begins not in the nuclear region but on the
periphery of the central lens. High-resolution
images of the lens itself show dust lanes and
luminous spiral filaments that can be traced as
close as 7" to the bright starlike nucleus.
NGC 5005 is a member of a special class of
low-power Seyfert galaxies, which Timothy
Heckman (University of Maryland) and Bruce
Balick (University of Washington) have dubbed
LINERs (low-ionization nuclear emission-line
regions). Although not as energetic as other
active galactic nuclei, LINERs share many of their
characteristics; they emit X-rays and vary in
brightness. As with all active galactic nuclei,
many astronomers believe black holes power
LINERs. LINERs are very common and may be
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