ASTEROIDAL OCCULTATION - REPORT FORM +------------------------------+ +------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +------------------------------+ +------------------------------+ 1 DATE: 2022/07/19 STAR: UCAC4 372-105430 ASTEROID: (643) Scheherezade 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 - 20:02:32 - - : D - 20:05:26.0 - - 0.2 : R - 20:05:31.4 - - 0.2 : E - 20:08:36 - - : Duration : 5.4 +/- 0.3 s Mid-event : 20:05:28.7 +/- 0.2 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: 450 ms 7 OBSERVING CONDITIONS: Atmospheric transparency: good Wind: no Temperature: 20 deg C Star image stability: fair Minor planet visible: yes 8 ADDITIONAL COMMENTS: Analyzed using Tangra v3.7.4 and AOTA v4.2022.7.5 S/N of occulted star: 5.4 - 5.7 (AOTA) Camera temperature: -15 deg C Measured light drop: 1.6 mag (AOTA) Applied approximate recording delay: 15 ms (based on the report for similar hardware configuration and the same both USB setting and ROI, and similar exposure, published by Pierre Le Cam on http://www.nocturno.fr/ost/ost.html) CentralEurope feed (2022/05/20): Event time: 20:05:27 UT Error in time: 3 s Max duration: 6.0 s Star magnitude: 14.0 m Asteroid magnitude: 15.3 m Combined magnitude: 13.7 m Magnitude drop: 1.4 - 1.6 m Position: In the shadow, 58 km from the central line Probability: 61.4 %