These are the most frequently used words in this book.
angle
anomaly
approximation
ascension
au
axis
between
break
calculate
calculated
calculation
case
comet
const
coordinates
cos
data
date
day
deg
determined
difference
distance
double
earth
eclipse
ecliptic
elements
endl
ephemeris
epoch
equation
equatorial
equinox
example
fig
file
first
function
geocentric
given
heliocentric
hour
however
include
int
interval
j2000
julian
known
latitude
longitude
lunar
may
mean
method
moon
motion
observation
observer
obtain
orbit
orbital
output
perihelion
perturbations
phase
plane
planet
point
position
program
rad
required
return
right
rotation
series
shadow
sin
solar
solution
star
step
sun
system
terms
therefore
three
time
total
tout
two
use
used
values
vec3d
vector
void
year