(*) Nota: Revised version v2.1 of phesat95.exe on November 1994 ---------------------------------- PHESAT95 Saturnian events of the 1995 period ftp anonymous server : ftp.bdl.fr ========================== ---------------------------------- This set of files contains data concerning the events occurring in the Saturnian satellites system from 1992 to 1999. A part of these predictions have been published in: Arlot, J.E. and Thuillot, W.: 1993, Eclipses and Mutual events of the first eight Saturnian satellites during the 1993-1996 period. Icarus 105, 427. 1. Description of the files: ------------------------ 1.1 ascii sequential files: The following files are avalaible under their compressed version (compressed thanks to the gzip command). Use the gunzip command to uncompress them. You will obtain: TABLE4.dat: selected dates of eclipses by Saturn (table 4 extracted from Arlot and Thuillot, 1993) TABLE5.dat: selected dates of mutual events of the Saturnian satellites (table 5 extracted from Arlot and Thuillot, 1993) ECL95.dat: data for the eclipses by Saturn from 1992 to 1998 PH92 to 99: data for the whole set of events involving the planet from 1992 to 1999 (transits, umbra, occultations and eclipses) PHM95.DAT: data concerning the mutual eclipses and occultations from the end of 1994 to the beginning of 1997 1.2 compressed set of PC files: phenpc.exe is a self extractor PC file. Copy it on the hard disk of your PC and run phenpc. You will obtain the following files: (*) PHESAT95.exe: PC software to be used in order to read selected records from the previous files. This selection is made thanks to parameters such as heigth of Saturn above the horizon, height of the Sun, distance to the planet... SATURN.INI: setup file used by Phesat95.exe SATURN.HLP: help file used by Phesat95.exe HAUSA92 to 99:files of planetary positions used by Phesat95.exe (don't modify them) . HAUSO92 to 99:files of solar positions used by Phesat95.exe (don't modifythem) LONGIT.DAT: file used by Phesat95.exe which contain the names and coordinates of the different sites from where you could compute the local conditions of observation. Insert your own coordinates in it thanks to any editor or thanks to the L command of phesat95.exe. 2. Description of the data: ----------------------- Instead of using the Phesat95.exe software to get the selected data you can directly read these data in the files PH92.DAT to PH99.DAT, ECL95.DAT or PHM95.DAT. These files contain records with the following format. In all these files, the satellites are numbered as following: 1: Mimas 2: Encelade 3: Thetys 4: Dione 5: Rhea 6: Titan 7: Hyperion 8: Iapetus File PHx.DAT: eclipses, shadows, transits and occultations Y M D H M S PHEN X Y D E MO SU 1992 9 3 14143.0 1ECR 0.74 0.75 33 1.0 73 152 Y M D: year month day H M S: hour minute second in Terrestrial Time (TT): date of the mid eclipse (50% light flux drop) or mid event (bissection of the satellite or its umbra by the edge of Saturn). Substract TT-TU values (about 60 seconds) in order to get the TU dates PHEN: type of phenomenon: 1ECR means eclipse of Mimas reappearence. ECD and ECR means eclipse disappearence and reappearence OCD and OCR means occultation disappearence and reappearence TRI and TRE means transit ingress and egress SHI and SHE means transit of the shadow ingress and egress X Y: differential coordinates of the satellites in radius of Saturn in the saturnocentric frame with X axis to the East, Y axis to the North D: semi-duration of the phenomenon. You have to substract and add this duration to the H M S value in order to get the first and last contacts. E: distance of the satellite to the edge of Saturn in arcseconds. MO SU: distance of the satellite to the Moon and Sun in degrees. File PHM95.DAT: mutual events. Y M D A PHE B T H1 M1 S1 H2 M2 S2 H3 M3 S3 H4 M4 S4 H5 M5 S5 H6 M6 S6 H7 M7 S7 LF D SA I I' M S 1994 11 24 3 ECL 2 P 11 37 5 11 38 0 11 46 7 11 54 9 11 55 4 0.563 1079 0.5 0.069 0.115 154 94 1995 1 13 2 ECL 3 P 8 14 54 8 18 36 8 50 5 9 21 54 9 24 53 0.185 4199 1.9 0.054 0.116 95 46 Y M D: year month day A PHE B T: satellite A eclipses (PHE is ECL) or occults (PHE is OCC) satellite B. This phenomenon is of type T. Parameter T can be: C means Conjunction: grazing mutual occultation.The time H4 M4 S4 gives the time of least distance. A means Annular P means Partial T means Total p means by the penumbra (mutual eclipses) H1 M1 S1: date of the first contact with the penumbra during a mutual eclipse. This time and the following times are in Terrestrial Time scale (TT): substract TT-TU values (about 60 seconds) in order to get the TU values. H2 M2 S2: date of the first contact with the umbra (EC) or with the satellite (OC) during the ingress. H3 M3 S3: date of the second contact H4 M4 S4: hour minute second in Terrestrial Time (TT): date of the mid event (maximum of light flux drop) H5 M5 S5: date of the first contact with the umbra (EC) or with the satellite (OC) during the egress H6 M6 S6: date of the second contact H7 M7 S7: date of the last contact with the penumbra during a mutual eclipse. LF: light flux drop (from 0 to 1) D: duration in seconds SA: distance from the center of Saturn in Saturnian radius I: impact parameter in arcseconds (distance between the two centers for occultations or between the eclipsed center and the axis of the umbra cone) I': sum of the radii in arcseconds (to appreciate how far from the grazing phenomenon is I) M: angular distance of the Moon in degrees S: angular distance of the sun in degrees 3. Campaign of observation: ------------------------ IMPORTANT Call for the observation of the Saturnian events ------------------------------------------------ These predictions will allow you to observe rare phenomena which occur every 15 years. We have organized an international campaign to collect this type of data which are of high interest for dynamical studies and space exploration of the Saturnian satellites system. We are interested to receive the observations of the eclipses by Saturn and the mutual events. Photometric or CCD observations are welcome but visual observation may also be of interest. Be careful to the time scale! ---------------------------- For the analysis we need to get a timing of the events in the Universal Time scale. We wish an accuracy better than 1 seconde of time. Well equiped observers can get lightcurves or CCD images from which photometric analysis will allow us to get physical parameters concerning the surface of the satellites and positional measurements. A high positional precision can be obtained from such records (down to 100 km). A complete set of photometric measurement must include measurements of reference stars (solar spectral type or other satelites) and measurements of the involved satellites before and after the phenomenon. Visual observations could be light flux measurements versus UT timing if you practise light flux measurements by comparison with other satellites or stars. If you don't practise this method, measure the time of the mid event (50% light flux drop) for the eclipses and measure the time of maximum of light flux drop for the mutual events. ----------------------------------------------- CONTACT ADDRESS _________ For any further informations please contact us to the following address: J.E. Arlot and W. Thuillot PHESAT95 Campaign Bureau des Longitudes Unite Associee au CNRS 707 77 Avenue Denfert Rochereau F-75014 PARIS (France) Phone : (33) 1 40 51 22 70 Fax : (33) 1 46 33 28 34 E-Mail : thuillot@bdl.fr / arlot@bdl.fr ----------------------------------------------- (c) 1992,1994 Bureau des Longitudes v2.1