These are the most frequently used words in this book.
another
appears
arms
astronomers
between
binoculars
bright
brighter
brightest
brightness
catalogue
center
central
close
cloud
cluster
comet
con
contains
core
dark
dec
detail
dia
diameter
dim
disc
discovered
dist
double
drawing
east
even
eye
faint
fainter
field
find
first
galaxy
globular
glow
halo
high
large
lies
light
look
low
mag
magnitude
members
messier
milky
million
nebula
nebulosity
ngc
night
north
northeast
northwest
now
nucleus
objects
observed
open
outer
patches
photographs
position
power
ra
refractor
region
see
seen
shows
sky
slightly
small
south
southwest
spiral
stars
suns
telescope
though
three
time
two
type
use
view
virgo
visible
vision
west
without
years