=========================== ============================
IMCCE - Observatoire de Paris
/pub/ephem/satel/phensaturne
=========================== ============================
Phenomena of the Saturnian satellites:
These files give the predictions (in Terrestrial Time) of
the phenomena (eclipses, occultations, transits and shadows) of the
eight first satellites of Saturn.
AUTHORS : W. Thuillot
ADDRESS : IMCCE - Observatoire de Paris
77 av. Denfert Rochereau, F-75014 PARIS
Phone: (1) 40 51 22 62
Fax: (1) 46 33 28 34
e-mail: thuillot@imcce.fr
CONTENTS:
phenF-Sn.dat:
phenE-Sn.dat:
French version (phenF-Sn.dat) or English version (phenE-Sn.dat) of the
predictions of the phenomena involving the planet and its satellites,
for every satellite Sn (with n: number of the satellite). These files
contain the predictions for the season 2006-2013 of the following events
(with the English codes):
EC.D and EC.R for Eclipse Disappearence and Reappearence
OC.D and OC.R for Occultation Disappearence and Reappearence
TR.I and TR.E for Transit Ingress and Egress (in front of Saturn)
SH.I and SH.E for Shadow transit Ingress and Egress (in front of Saturn)
The Saturnian satellites are numbered as following:
1: Mimas
2: Enceladus
3: Tethys
4: Dione
5: Rhea
6: Titan
7: Hyperion
8: Iapetus
These predictions give the dates t of the mid-event.
These dates t are given in the TT timescale (Terrestrial Time
close to TAI + 32.184 s). The UT dates tUT in the Universal Time timescale can
be obtained by:
tUT = t - (TT - TU)
when we know the TT - TU difference.
It is the case for the past years (see the table below)
For the future, we can use the last known value.
-----------------------------
Period TT-TU(s)
-----------------------------
1/1/2006-1/1/2009 65
1/1/2009- 66
-----------------------------
The format of the records is given in the following example, where
sat, phen, yy, mm, hh, mm.m, s designed the number of the satellite,
the phenomenon, the year, month, hour, minute, second (in TT); X and Y
are the differential coordinates of the satellite (X toward East,
Y toward North) expressed in planet radius; sd is the semi-duration of
the event ewpressed in seconds (i.e. half of the time elapsed between
first and last contact with the umbra cone or the visibility cone);
d is the approximate apparent distance of the satellite centre from
the edge of the planet expressed in arcsec.
We have for example for the first transit and occultation of S6 Titan,
then for an eclipse and an occultation:
sat phen an m j hh mm ss X Y sd d
6 TR.I 2008 10 19 21. 2. 21. 0.3 0.9 1296. 0.
6 TR.E 2008 10 19 23. 15. 45. -0.5 0.8 -1297. 0.
6 OC.D 2008 10 27 21. 50. 52. -0.5 -0.8 920. 0.
6 OC.R 2008 10 28 1. 19. 8. 0.6 -0.7 -914. 0.
.../...
6 EC.D 2009 3 20 10. 27. 37. -0.1 -1.1 897. 2.
6 EC.R 2009 3 20 13. 59. 44. 1.0 -1.0 -897. 5.
6 SH.I 2009 3 28 8. 26. 51. 0.0 1.1 699. 2.
6 SH.E 2009 3 28 12. 25. 53. -1.4 1.0 -700. 7.
NOTES:
1. These predictions are based on the TASS 1.6 ephemerides
(Vienne & Duriez, 1995). Each event is computed for the satellite centre.
For the eclipses, the mid event corresponds with a good approximation to the
half brightness of the satellite. For the other phenomena, this correspond to
the bisection of the satellite (OC, TR) or of its shadow (SH).
2. Depending on the geometrical circumstances, the visibility cone which
defines the occultations and the shadow transits, and the umbra cone which
defines the eclipses and the occultations, can overlap. In these cases, the
disappearence or reappearence of an eclipse, or of an occultation may be
not visible because the satellite is occulted or eclipsed.
REFERENCES:
Thuillot W.: 1983, A&A 127, 63-67.
Vienne A., Duriez L.: 1995, A&A 297, 588-605
NB:
THE USE OF THESE DATA IS SUBJECTED TO CONDITIONS.
MORE INFORMATIONS ARE AVAILABLE ON THE WEB PAGE BELOW:
http://www.imcce.fr/page.php?nav=fr/site/copyright.php?top=1
================================================================================
User feed-back is encouraged. Unless otherwise specified, send comments and bug
reports to: E-mail : comments@imcce.fr
Fax : (33) 1 46 33 28 34
Postal mail: IMCCE - Observatoire de Paris
77 avenue Denfert Rochereau
F-75014 PARIS
================================================================================