These are the most frequently used words in this book.
23x
another
appears
arms
astronomers
between
binoculars
bright
brighter
brightest
brightness
caldwell
catalog
center
central
cloud
cluster
companions
core
dark
dec
diameter
dim
distance
double
dust
east
edge
end
even
eye
faint
fainter
field
find
first
found
galaxy
gas
globular
glow
herschel
high
ic
known
large
lies
light
little
look
mag
magnitude
may
members
milky
million
nearly
nebula
nebulae
nebulosity
ngc
night
north
objects
observers
open
pair
part
photographs
planetary
position
power
ra
region
ring
second
see
seems
seen
should
show
sky
small
south
southern
southwest
space
spiral
stars
suns
telescope
though
time
two
type
view
vision
visual
william
years