Comments: 1. The format does not include any computed data items. 2. The format covers both the ILOC dataset, the RGO dataset, and future observations. 3. Provision is made to record corrections to the data, without losing the original data. Three types of correction are envisaged: (1) date/time (2) star identifier, and (3) site coords. Byte(s): (Format) Description *********************************************** * Group 1 Time and Object (34) * *********************************************** *** The data in this group incorporates any corrections made to the time and object. The original data is maintained in groups 8 and 9 *** 1- 4: (I4) Year [Note: full year required - such as '2008'] 5- 6: (I2) Month 7- 8: (I2) Day 9- 10: (I2) Hour 11- 12: (I2) Minute 13- 18: (F6.3) Second. Number of decimal places is given according to accuracy. 19 : (A1) Star catalogue / object type R Zodiacal Catalogue S SAO catalogue X XZ80Q catalogue A Numbered asteroid P Planet and planet satellites U Unidentified star 20- 25: (I6) Number in catalogue For an Unidentified star - blank For planets, number is formed as pmmm, where: p = planet number mmm = moon number. Set to 000 for occultation of planet. eg Mercury = 1000, Jupiter = 5000, Ganymede = 5003, Titan = 6006 For asteroids: asteroid number. [Unnumbered asteroids cannot be specified] 26 : (A1) WDS double star component identifier (A - Z, a - z) 27 : (A1) Phenomena D disappear R reappear B Blink. The mid-time of a blink event. Usually only occurs during a graze, but can occur in near-graze situations. Duration is specified at column 48. (video) partial disappearance (always >25% of full light). (visual) a short disappearance-reappearance - too close to separately time. f flash. the mid-time of a flash event. usually only occurs during a graze, but can occur in near-graze situations. duration is specified at column 48. (video) partial reappearance (always <25% of full light). (visual) a short reappearance-disappearance - too close to separately time. M Miss. The time when the star was adjacent the highest point on the observed or predicted graze profile. Only used when other observers in a graze observation have recorded D &/or R events S Start or resume. Only used in a graze observation, to indicate periods when the observer was obsrving. E End or pause. Only used in a graze observation, to indicate periods when the observer was not obsrving. O Other [used by ILOC instead of S or E] 28 : (A1) Limb D dark limb B bright limb (including lunar eclipse penumbra) U umbra of lunar eclipse 29 : (A1) Graze flag G graze event <> ordinary occultation 30- 33: (F4.2) Personal equation. Range 0.00 to 9.99 sec. Blank if PE not applicable. 34 : (A1) Application of Personal equation S personal equation has been subtracted from the observed time. A = S, but PE listed is an assumed value. [compatibility for ILOC observations] B = S, but the value of the PE applied is unknown. [compatibility for RGO observations] U personal equation has not been subtracted from the reported time. E personal equation not relevant to the method of timing (eg video, eye-ear) X Not known whether any PE has been applied. *********************************************** * Group 2 ILOC observation codes (24) * *********************************************** 35 : (A1) Method of timing and recording G Video with time insertion, times extracted by frame analysis V Video with other time linking, times extracted by frame analysis M Video with other time linking, times extracted by replay S Stopwatch (visual) T Tape recorder (visual) E Eye and ear P Photoelectric K Key-tapping - including computer keyboards X Chronograph C Camera and clock 36 : (A1) Method of timing and recording (2) Same definitions as for (35), plus the following. Blank if no second method was used. A Time base corrected using adjacent observers 37 : (A1) Time source G GPS (using 1PPS output, NOT GPS screen display) R Radio signal (standard time signal) N Network Time Protocol (using NTP software) C Clock(adjusted by standard time signal) T Telephone M Some medium related with standard time signal O GPS screen display, computer clock not using NTP software (poor accuracy). 38- 42: (F5.3) Accuracy of time. Range 0.000 to 9.999. Blank if no figure provided. 43 : (A1) Certainty 1 Sure 2 Possibly spurious 3 Most likely spurious 44- 46: (F3.1) Signal-to-Noise ratio (for video & photoelectric). Range 0.0 to 9.9. Blank if not relevant, or not provided. 47 : (A1) Double star / unidentified star <> No double star effect noted W Preceding (west) component E Following (east) component N North component S South component B Brighter component F Fainter component U Unidentified star 48- 52: (F5.3) Duration of non-instantaneous event. Range 0.000 to 9.999 secs. Blank if not relevant. 53 : (A1) Light level at event (for video & photoelectric, if event is non-instantaneous) <> Not specified T 25% light level (consistent with fresnel diffraction) F 50% light level (consistent with stellar diameter effects) 54 : (A1) Sky stability <> Not specified 1 Good 2 Fair 3 Poor 55 : (A1) Sky transparency <> Not specified 1 Good 2 Fair 3 Poor 56 : (A1) Remarkable circumstances <> No remarkable circumstances 1 Gradual[not instantaneous] event 2 Dark limb visible 3 By averted vision 4 Star faint 5 Through thin cloud 6 Many clouds 7 Strong wind 8 In strong twilight 9 In daylight (sun altitude >-6 deg {civil twilight}) 57- 59: (i3) temperature centigrade. range -49 to 50. blank if not provided. *********************************************** * group 3 rgo observation codes (4) * *********************************************** *** these codes are used for observations prior to 1981 *** 60 : (a1) accuracy 1 excellent, very good (+/- 0.1s, +/- 0.2s) 2 good, certain (+/- 0.3s, +/- 0.4s) 3 fair, satisfactory (+/- 0.5s to +/- 0.7s) 4 poor, uncertain (+/- 0.8s, +/- 0.9s) 5 very poor, very doubtful (+/- 1s) 6 star faint 7 perhaps early 8 perhaps late 9 uncertain by tens of seconds 61 : (a1) condition <> not specified 1 clear, good conditions 2 haze, mist, thin cloud 3 cloud 4 difficult conditions 5 not instantaneous, gradual 6 dark limb visible 7 by averted vision 8 during lunar eclipse 9 obvious mistake corrected on report 62 : (a1) time adjusted; double star 2 reported time adjusted by integral number of minutes, hours, etc, for obvious mistake 8 component of double star (observations of components of double or compound star systems which do not have positions in the zc or saoc are indicated by an '8') 63 : (a1) timing method <> not known 1 photoelectric 2 eye-and-ear 3 chronograph 4 stopwatch and time-signal 5 stopwatch and telephone time-signal 6 camera and clock 7 eye-and-ear with sidereal chronometer 8 chronograph and sidereal clock 9 tape recorder and time signal 0 not known *********************************************** * group 4 compilation/edit codes (8) * *********************************************** 64- 73: (a10) future use 74 : (a1) observation validity <> valid a valid, after adjustments to the date/time. b valid, after adjustments to the star number. c valid, after adjustments to both the date/time and star number. d valid, after adjustments to site coordinates. e valid, after adjustments to site coordinates and date/time. f valid, after adjustments to site coordinates and star number. g valid, after adjustments to site coordinates and star number and date/time. [note for codes d, e, f & g: adustments to site coordinates are made on the basis of all observations made from a site, and not on an event-by-event basis.] s unknown site location. [used for rgo and iloc data, where there is no site data for the specified station.] t poor time base [for events before 1850] u unidentified star [including star is not in the xz80q catalogue] w invalid site location. the site location is definitely in error (eg site located in the sea, or all observations from the location have large residuals), and the correct location cannot be deduced (eg obvious transposition of digits in the reported site coordinates). x assessed as an invalid observation. on investigation, confident the relevant occultation and observing location has been identified, with a conclusion that the event was not actually observed for some reason - such as difficult conditions. y limb-corrected residual greater than about 4". This is a flag automatically generated to indicate the computed residual is unsatisfactory. The exact criteria applied depends on the basis for correcting the limb for its irregularities. Events with this flag have not been individually investigated to determine whether there is an error in the reported data, or whether the observation was adversely affected by poor observing conditions (that is, is invalid). Z Unresolved data errors. After considering the possibility of errors in several of date + time, star, and site location, the reported observation cannot be plausibly associated with a relevant occultation. 75- 78: (I4) Graze identifier - year 79- 81: (I3) Graze identifier - number in year *********************************************** * Group 5 Site location (96) * *********************************************** *** The data in this group incorporates any corrections made to the site coordinates or datum. The original data is maintained in group 10 *** 82 : (A1) Sign of longitude, +'ve to East 83- 85: (I3) degrees of longitude 86- 87: (I2) minutes of longitude 88- 92: (F5.2) seconds of longitude 93 : (A1) Sign of latitude, +'ve to North 94- 95: (I2) degrees of latitude 96- 97: (I2) minutes of latitude 98-102: (F5.2) seconds of latitude 103-104: (I2) Horizontal datum code *** datum codes used with pre 1981 events (RGO data) *** <> not known 1 geodetic, referred to one of the following major datum blocks; 1927 North American Datum, European Datum or Australian Geodetic Datum 2 geodetic, either referred to one of the secondary datum blocks, such as Tokyo Datum or African Arc Datum, or are referred to a national datum, such as the 1936 Ordnance Survey of Great Britain 3 probably geodetic 4 probably astronomic 5 astronomical 10 Measured using GoogleEarth *** ILOC datum codes used with post 1980 events *** 14 BRAZIL, 16 ED/ED1950/ED1979, 17 AZORES, 22 INDIAN, 26 LUZON1991 28 NZ1949, 29 NAD27/NAD1927, 30 CAPECANAWERAL, 31 WHITESANDS 33 OLDHAWAIAN, 34 ORDN1936, 35 ORDNCANARIES, 37 POTSDAM 38 PROV1956, 39 HITO1963, 40 PULKOVO, 41 SA69, 46 TOKYO/TD 63 ARCCAPE, 64 CAMPO-INCHAUSPE(ARG.), 66 AUSTRALIAN-GEODETIC/AU1966 73 HERMANNSKOGEL, 80 ETRS89, 81 AMER1885, 82 NAD83/NAD1983 84 GPS84/WG-84/WGS84, 85 JGD2000, 86 GDA94, 87 NZGD2000 88 NGRF2000, 89 KDG2000, 90 Hartebeesthoek94, 91 TWD94 105-110: (F6.1) Altitude (meters) [range -999.9 to +9999.9] 111 : (A1) Vertical datum code M Mean Sea Level E Ellipsoid. [for use when a GPS unit does not correct computed elevations for the difference between the Ellipsoid and Mean Sea Level.] 112-120: (A9) ILOC Station + Telescope code 121-127: (A7) RGO station + Observer code 128-177: (A50) Closest town or landmark to site, and Country - comma separated. *********************************************** * Group 6 Telescope details (11) * *********************************************** 178 : (A1) Type of telescope R Refractor [including Achromatic, Apochromatic, binoculars, and camera lenses] N Newtonian reflector [including Dobsonian, Schmidt-Newtonian, Maksutov-Newtonian, Jones-Bird, Schiefspiegler] C Cassegrain, [including Schmidt-Cassegrain, Maksutov, Ritchy-Chretien, Dall-Kirkham] O Other, including naked eye. <> not known 179 : (A1) Mounting E Equatorial mounting A Alt-Azimuth mounting <> not known 180 : (A1) Driving D Driven M Manual <> not known 181-184: (I4) Telescope aperture (cm) - rounded to the nearest cm. 185-188: (I4) Telescope focal length (cm) - rounded to the nearest cm. *********************************************** * Group 7 Observer names (25) * *********************************************** 189-213: (A25) Observer name *********************************************** * Group 8 Original date/time (18) * *********************************************** *** The original date and time are given in this group *** 214-217: (I4) Year 218-219: (I2) Month 220-221: (I2) Day 222-223: (I2) Hour 224-225: (I2) Minute 226-231: (F6.3) Second *********************************************** * Group 9 Original object (7) * *********************************************** *** The original object number is given in this group. *** 232 : (A1) Star catalogue R Zodiacal Catalogue S SAO catalogue X XZ80Q catalogue A Numbered asteroid P Planet and planet satellites U Unidentified star 233-238: (I6) Number in catalogue For an Unidentified star - blank For planets, number is formed as pmmm, where: p = planet number mmm = moon number. Set to 000 for occultation of planet. eg Mercury = 1000, Jupiter = 5000, Ganymede = 5003, Titan = 6006 For asteroids: asteroid number. Unnumbered asteroids cannot be specified. *********************************************** * Group 10 Original site coordinates [30+2] * *********************************************** *** The original site coordinates are given in this group. *** 239 : (A1) Sign of longitude, +'ve to East 240-242: (I3) degrees of longitude 243-244: (I2) minutes of longitude 245-249: (F5.2) seconds of longitude 250 : (A1) Sign of latitude, +'ve to North 251-252: (I2) degrees of latitude 253-254: (I2) minutes of latitude 255-259: (F5.2) seconds of latitude 260-261: (I2) Horizontal datum code *** datum codes used pre 1981 (RGO data) *** <> not known 1 geodetic, referred to one of the following major datum blocks; 1927 North American Datum, European Datum or Australian Geodetic Datum 2 geodetic, either referred to one of the secondary datum blocks, such as Tokyo Datum or African Arc Datum, or are referred to a national datum, such as the 1936 Ordnance Survey of Great Britain 3 probably geodetic 4 probably astronomic 5 astronomical 10 Measured using GoogleEarth *** ILOC datum codes used post 1980 *** 14 BRAZIL, 16 ED/ED1950/ED1979, 17 AZORES, 22 INDIAN, 26 LUZON1991 28 NZ1949, 29 NAD27/NAD1927, 30 CAPECANAWERAL, 31 WHITESANDS 33 OLDHAWAIAN, 34 ORDN1936, 35 ORDNCANARIES, 37 POTSDAM 38 PROV1956, 39 HITO1963, 40 PULKOVO, 41 SA69, 46 TOKYO/TD 63 ARCCAPE, 64 CAMPO-INCHAUSPE(ARG.), 66 AUSTRALIAN-GEODETIC/AU1966 73 HERMANNSKOGEL, 80 ETRS89, 81 AMER1885, 82 NAD83/NAD1983 84 GPS84/WG-84/WGS84, 85 JGD2000, 86 GDA94, 87 NZGD2000 88 NGRF2000, 89 KDG2000, 90 Hartebeesthoek94, 91 TWD94 262-267: (F6.1) Altitude (meters) [range -999.9 to +9999.9] 268 : (A1) Vertical datum code M Mean Sea Level E Ellipsoid. [for use when a GPS unit does not correct computed elevations for the difference between the Ellipsoid and Mean Sea Level.] 269-270: (A2) CR/LF sequence NOTES All Text fields [Ax] are left justified. All integer fields [Ix] are right justified. All floating point fields are aligned by the decimal point. For floating point fields, the number of decimal places used is determined by the accuracy of the reported data. The remainder of the field is padded with spaces, not zeros. ******************************************************************************************************** VERSION history V 1.0 1 September 2008 Released ********************************************************************************************************
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