Astronomical Applications Department, U.S. Naval Observatory Precession Maple Page 42
We can determine the approximate angles
at which the precession is zero. From
precession_rate
(
)
-
+
(
)
cos
Z
Y
(
)
sin
( )
cos
X
(
)
sin
( )
sin
(
)
G
, , ,
,
,
a b h A
C
A
T
(
-
=
(
)
-
-
+
(
)
sin
Z
(
)
cos
Y
( )
cos
( )
sin
(
)
cos
X
(
)
- +
1
I
xy
(
)
sin
)
(
)
we see that for
=
0
we must have
=
(
)
G
, , ,
,
,
a b h A
C
A
T
0
. Hence, we require
=
(
)
rhs
(
)
op
(
)
select
,
,
has gsubs G
P
0
(
)
-
a
b (
)
-
+ +
A
C
1
2 A
C
( )
cos
2
(
)
+
( )
sin
h
( )
cos
a (
)
+
a
b
( )
sin
-
-
1
3
( )
cos
(
)
-
a
b A
C
( )
sin
( )
cos
(
)
-
a
b
( )
sin
(
)
+
+
a
2
a b
b
2
a
2
h (
)
- +
1
A
T
+
+
0
=
(
)
latex
,
% "d:/dynamics/precession/PrecessionNullEq.tex"
Plots
Analytic
save "d:/dynamics/precession/precession.m"
restart
(
)
alias
=
I
I
alias
=
( )
t
=
( )
t
=
( )
t
=
x
( )
x
t
=
y
( )
y
t
=
z
( )
z
t
=
( )
t
=
( )
t
,
,
,
,
,
,
,
,
(
=
( )
t )
read "d:/dynamics/precession/precession.m"
Id fn det size rows cols transpose inverse augment stack extend grad curl div laplacian angle
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
,
intparts
x
y
z
,
, , ,
,
,
,
,
,
?
Page 42
