+--------------------------------+ +--------------------------------+ ASTERIODAL OCCULTATION - REPORT FORM +--------------------------------+ +--------------------------------+ EAON & IOTA-ES EUROPEAN ASTEROIDAL OCCULTATION NETWORK INTERNATIONAL OCCULTATION TIMING ASSOCIATION EUROPEAN SECTION +--------------------------------+ +--------------------------------+ 1. DATE: 22 Dec 2017 STAR: 4UC 705-043934 ASTEROID: (1116) Catriona 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 : 01:43:00 -D : 01:48:11.90 ± 0.32 s -R : 01:48:16.38 ± 0.32 s -E : 01:53:00 Duration: 4.48 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 -Sensor/Camera: Videocamera WAT-910HX-RC, CCIR, 1/2", ICX429ALL sensor -Videocamera settings: Shutter = x32; 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 uncompressed file -Timekeeping: GPS 1PPS (US Global Sat EM-406A) -Time insertion device: IOTA-VTI, v.1.1.42 -Integration time: 0.640 s 7. OBSERVING CONDITIONS -Atmospheric transparency: fair/good -Wind: none -Star image stability: good -Minor Planet Visible during the occultation: yes 8. ADDITIONAL COMMENTS -Target position: elevation = 75 deg; azimut = 295 deg. Accordingly to Occultwatcher prediction, IBEROC feed: -Rank: 53 -Probability: 32.2 % -Combined magnitude: 12.7 mag -Star magnitude: 14.3 magV; 14.3 magR -Asteroid magnitude: 13.0 mag -Lightdrop: 0.29 mag; 0.2 magR -Max duration: 5.0 s -Event time: 01:48:08 UT -Error in time: 6 s -Moon distance: - -Moon illumination: - -Tangra v. 3.6.13 was used to generate the lightcurve (aperture photometry, average background). -Unfortunately the signal of the target (asteroid+star) was saturated during the 10 minutes of recording because the applied defocusing was too small. -A lightdrop of about 0.2 mag was measured. -A correction of -0.340 s was applied because of the use of an integration camera. -A lightcurve can be seen here: http://sposetti.ch/wp-content/uploads/2018/01/20171222_Catriona.png