These are the most frequently used words in this book.
2000
across
alpha
although
appears
arc
astronomers
away
between
binary
binoculars
bright
brighter
brightest
brightness
cloud
cluster
comet
comments
constellation
crater
dark
days
dec
deep
diameter
double
due
earth
easily
east
even
eye
faint
few
field
figure
first
form
found
galaxy
gc
giant
glasses
globular
glow
group
gx
known
large
lies
light
little
long
look
mag
magnitude
may
members
messier
miles
milky
moon
near
nearly
nebula
ngc
night
north
northern
object
observers
oc
open
pair
period
photograph
point
reveal
seen
set
sizelsepl
sky
small
south
southern
stars
stellar
sun
system
telescopes
three
time
two
typ
variable
view
visible
vr
years