+--------------------------------+ +--------------------------------+ ASTERIODAL OCCULTATION - REPORT FORM +--------------------------------+ +--------------------------------+ EAON & IOTA-ES EUROPEAN ASTEROIDAL OCCULTATION NETWORK INTERNATIONAL OCCULTATION TIMING ASSOCIATION EUROPEAN SECTION +--------------------------------+ +--------------------------------+ 1. DATE: 27 Feb 2018 STAR: 2UCAC 41158475 ASTEROID: (466) Tisiphone 2. OBSERVER Name: Stefano SPOSETTI Address: 6525 GNOSCA - Switzerland Email: stefanosposetti@ticino.com 3. OBSERVING STATION Nearest city: CH-6525 Gnosca Longitude: 9d 1m 26.5s (E) Latitude: 46d 13m 53.2s (N) Altitude: 260m (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 : 21:09:21 -D : 21:12:05.94 ± 0.04 s -R : 21:12:17.78 ± 0.04 s -E : 21:13:03 Duration: 11.84 s ± 0.08 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 -Sensor/Camera: Videocamera WAT-910HX-RC, CCIR, 1/2", ICX429ALL sensor -Videocamera settings: Shutter = x4; Gain = 40/41; Gamma = 1.00 -Device of recording: Personal computer, Imaging Source DFG/SV1 PCI, composite input, Virtualdub acquiring software, saved on Harddisk as Huffyuv compressed file -Timekeeping: GPS 1PPS (US Global Sat EM-406A) -Time insertion device: IOTA-VTI, v.1.1.42 -Integration time: 0.080 s 7. OBSERVING CONDITIONS -Atmospheric transparency: fair/bad, some clouds and Moonlight -Wind: none -Star image stability: fair -Minor Planet Visible during the occultation: no 8. ADDITIONAL COMMENTS -Target position: elevation = 54 deg; azimut = 251 deg. Accordingly to Occultwatcher prediction, IOTA feed: -Rank: 99 -Probability: 28.1 % -Combined magnitude: 11.7 mag -Star magnitude: 12.5 mag V -Asteroid magnitude: 14.2 mag -Lightdrop: 2.1 mag -Max duration: 11.1 s -Event time: 21:12:16 UT -Error in time: 4 s -Moon distance: 45 deg -Moon illumination: 94 % -Tangra v. 3.6.15 was used to generate the lightcurve (aperture photometry, average background). -A correction of - 0.060 s was applied because of the use of an integration camera. -A lightcurve can be seen here: http://sposetti.ch/wp-content/uploads/2018/03/20180227_Tisiphone.png