ASTEROIDAL OCCULTATION - REPORT FORM +------------------------------+ +------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +------------------------------+ +------------------------------+ 1 DATE: 2021/11/01 STAR: UCAC4 626-041775 ASTEROID: (3345) Tarkovskij 2 OBSERVER: Name: Daniel BLAZEWICZ Address: 32-015 Klaj, POLAND 3 OBSERVING STATION: Klaj Nearest city: Niepolomice (Poland) Longitude: E 20 19 04.2 (WGS84) Latitude: N 49 59 33.2 (WGS84) Altitude: 211 m (MSL) Single station +----------------------------+ 4 TIMING OF EVENTS: | | | EVENT REPORTED: POSITIVE | | | +----------------------------+ Event code S: observation Start I: Interruption start D: Disappearance J: Interruption end R: Reappearance B: Blink F: Flash E: observation End O: Other (specify) Abbreviations P.E.: Personal Equation = reaction time (for visual obs) Acc.: Accuracy (overall accuracy of the given time) Comments Event Time (UT) P.E. Acc. Code HH:MM:SS.ss S.ss S.ss S - 00:27:58 - - : D - 00:30:58.18 - - 0.15 : R - 00:31:01.33 - - 0.10 : E - 00:34:35 - - : Duration : 3.15 +/- 0.18 s Mid-event : 00:30:59.76 +/- 0.09 s 5 TELESCOPE: Type: NEWTON Aperture: 350 mm Magnification: prime focus f/4.8 Mount: EQUATORIAL with polar wedge Motor drive: YES 6 TIMING & RECORDING: Time source: "chrony", 4 x NTP Stratum 1, Linux Ubuntu, 1 sigma < 1 ms Sensor: ZWO ASI174MM-C Recording: ZWO ASICAP V2.3 Exposure: 200 ms 7 OBSERVING CONDITIONS: Atmospheric transparency: fair Wind: weak Temperature: 3 deg C Star image stability: fair Minor planet visible: very barely 8 ADDITIONAL COMMENTS: Analyzed using Tangra v3.7.3 and AOTA v4.12.15 S/N of occulted star: 7.6 - 7.7 (AOTA) Camera temperature: -20 deg C The applied approximate recording delay (24 ms) was based on the report for similar hardware configuration and the same both USB setting, ROI and exposure, published by Pierre Le Cam on http://www.nocturno.fr/ost/ost.html . Observed magnitude drop: ~ 2.5 m (measured manually in AOTA) Star not visible during occultation but Tangra light curve constains small posivite values. IBEROC feed (2021/10/08): Event time: 00:30:59 UT Error in time: 4 s Max duration: 2.1 s Star magnitude: 13.6 m Asteroid magnitude: 16.0 m Combined magnitude: 13.5 m Magnitude drop: 2.5 m Position: In the shadow, 5 km outside the shadow path Probability: 53.1 %