+--------------------------------+ +--------------------------------+ ASTERIODAL OCCULTATION - REPORT FORM +--------------------------------+ +--------------------------------+ EAON & IOTA-ES EUROPEAN ASTEROIDAL OCCULTATION NETWORK INTERNATIONAL OCCULTATION TIMING ASSOCIATION EUROPEAN SECTION +--------------------------------+ +--------------------------------+ 1. DATE: 21 Dec 2018 STAR: UCAC4-524-054132 ASTEROID: (326) Tamara 2. OBSERVER Name: Stefano SPOSETTI Address: 6525 GNOSCA - Switzerland Email: stefanosposetti@ticino.com 3. OBSERVING STATION Nearest city: CH-6525 Gnosca Station: 143 Longitude (DD MM SS.s): 09 01 26.5 (E) Latitude (DD MM SS.s): 46 13 53.2 (N) Altitude: 260 m (WGS84) 4. TIMING OF EVENTS Occultation recorded: POSITIVE Type of event: "S"tart observation; "I"nterrupt-start; "D"isappearance; "B"link; "F"lash; "E"nd observation; "I"nterrupt-end; "R"eappearance; "O"ther (specify) Personal Equation Substracted: - Event Time (UTC) Accuracy + Comments code: HH:MM:SS.ss S.sss -S : 03:06:39 -D : 03:07:32.62 ± 0.32 s -R : 03:07:34.54 ± 0.32 s -E : 03:08:33 Duration: 1.92 s ± 0.64 s 5. TELESCOPE -Type: Schmidt-Cassegrain, Celestron 11-inch -Aperture: 280 mm -Focal length: 930 mm (with focal reducer) -Magnification: FOV 23x18 arcmin -Mount: Equatorial -Motor drive: Yes 6. TIMING & RECORDING -Camera/Sensor: Videocamera WAT-910HX-RC, CCIR, 1/2" -Videocamera settings: Shutter = x32, Gain = 37/41, Gamma = 1.00 -Device of recording: Personal computer -Grabber: Imaging Source DFG/SV1 PCI, composite input -Software: Virtualdub v. 1.10.4, saved on Harddisk as Lagarith compressed file -Time insertion device: IOTA-VTI, v.1.1.42 -Timekeeping: GPS 1PPS (US Global Sat EM-406A) -Integration time: 0.640 s 7. OBSERVING CONDITIONS -Atmospheric transparency: very poor (+2 mag naked eye luminosity, sky illuminated by the Moon) -Wind: none -Star image stability: fair/good -Minor Planet visible during the occultation: no 8. ADDITIONAL COMMENTS Prediction: -Occultwatcher, IOTA feed -Rank: 100 -Probability: 83.7 % -Combined magnitude: 11.9 mag -Star magnitude: 12.0 magV -Asteroid magnitude: 14.2 mag -Lightdrop: 2.33 mag -Max duration: 4.5 s -Event time: 03:07:31 UT -Error in time: 1 s -Moon distance: 120 deg -Moon illumination: 96 % Other comments: -Target sky position: elevation = 38 deg, azimut = 110 deg -Tangra v. 3.6.18 was used to generate the lightcurve (aperture photometry, average background) -A correction of - 0.340 s was applied because of the use of an integration camera (so called "Dangl-correction") -Measured lightdrop: none -A lightcurve can be seen here: http://sposetti.ch/wp-content/uploads/2018/12/2018_12_21_Tamara_Gnosca.png