J/A+A/324/366 Theory of motion & ephemerides of Hyperion (Duriez+ 1997)
Theory of motion and ephemerides of Hyperion
Duriez L., Vienne A.
<Astron. Astrophys. 324, 366 (1997)>
=1997A&A...324..366D 1997A&A...324..366D (SIMBAD/NED BibCode)
ADC_Keywords: Planets ; Ephemerides
Keywords: Celestial mechanics - planets and satellites: Hyperion - ephemerides
Description:
In this paper, we present a new theory of motion for Hyperion, defined
like in TASS1.6 for the other Saturn's satellites (Vienne & Duriez,
1995A&A...297..588V 1995A&A...297..588V), by the osculating saturnicentric orbital
elements referred to the equatorial plane of Saturn and to the node of
this plane in the mean ecliptic for J2000.0. These elements are
expressed as semi-numerical trigonometric series in which the argument
of each term is given as an integer combination of 7 natural
fundamental arguments (Table 3). These series (Tables 4 to 7) collect
all the perturbations caused by Titan on the orbital elements of
Hyperion, whose amplitudes are larger than 1km in the long-period
terms and than 5km in the short-period ones. Taking also account of
the perturbations from other satellites and Sun (Table 8), these
series have been fitted to 8136 Earth-based observations of Hyperion
in the interval [1874-1985]. The resulting series allows to produce
new ephemerides for Hyperion, which have been compared to those
previously given by Taylor (1992A&A...265..825T 1992A&A...265..825T): Using the same set
of observations and the same way to weight them, the root mean square
(o-c) residual of the present theory is 0.156-arcseconds while the
ephemerides of Taylor gives 0.203-arcseconds.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3 74 7 Fundamental arguments of the theory
table4 70 105 Series for element p of Hyperion
table5 70 214 Series for element q of Hyperion
table6 70 179 Series for element z of Hyperion
table7 70 52 Series for element zeta of Hyperion
table8 92 46 Solar and short period perturbations of Hyperion
tables.tex 102 1029 *Tables 3 to 8 in plain TeX format (1)
--------------------------------------------------------------------------------
Note on tables.tex: in the same form exactly as the corresponding tables
published in A&A
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Num Number of the argument
4- 8 A5 --- Arg Argument, see note (1)
9- 33 D25.15 rad/d Freq Frequency
34- 58 D25.15 rad Phas Phase
59- 74 F16.6 d Per ? Period
--------------------------------------------------------------------------------
Note (1): psi: Synodic argument between Titan and Hyperion
tau: argument of the libration
pi7: longitude of the proper pericentre of Hyperion
pi6: longitude of the proper pericentre of Titan
Om7: longitude of the proper node of Hyperion
Om6: longitude of the proper node of Titan
Om0: longitude of the node of the invariable plane
Each argument is (Freq * t + Phas) where: t = Julian Date - 2451545.0
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4 table5 table6 table7
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Num Number of the term
4- 28 D25.15 rad Ampl Amplitude
29- 32 I4 --- N1 Argument (1)
33- 36 I4 --- N2 Argument (1)
37- 40 I4 --- N3 Argument (1)
41- 44 I4 --- N4 Argument (1)
45- 48 I4 --- N5 Argument (1)
49- 52 I4 --- N6 Argument (1)
53- 56 I4 --- N7 Argument (1)
57- 70 F14.2 d Per ? Period
--------------------------------------------------------------------------------
Note (1): The argument of each term has to be computed as:
N1*psi + N2*tau + N3*pi7 + N4*pi6 + N5*Om7 + N6*Om6 + N7*Om0
where psi, tau, pi7, pi6, Om7, Om6, Om0 are given in table3.
This is the argument of a cosine in table4, of a sine in table5
and of a complex exponential in table6 and table7
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table8
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- Ser Element of Hyperion (1)
4- 28 D25.15 rad Ampl Amplitude
29- 53 D25.15 rad/d Freq Frequency
54- 78 D25.15 rad Phas Phase
79- 92 F14.2 d Per ? Period
--------------------------------------------------------------------------------
Note (1): p7 : perturbation of element p of Hyperion (series in cosine)
q7 : perturbation of element q of Hyperion (series in sine)
z7 : perturbation of element z of Hyperion (series in complex
exponential)
zt7: perturbation of zeta of Hyperion (series in complex exponential)
The argument of each term is: (Freq * t + Phas),
where: t = Julian Date - 2451545.0
--------------------------------------------------------------------------------
Acknowledgements: L. Duriez
(End) Patricia Bauer [CDS] 06-Mar-1997