ASTEROIDAL OCCULTATION - REPORT FORM +------------------------------+ +------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +------------------------------+ +------------------------------+ 1 DATE: 2022/08/09 STAR: UCAC4 417-144537 ASTEROID: (1585) Union 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 - 22:22:00 - - : D - 22:24:14.4 - - 0.3 : R - 22:24:16.8 - - 0.3 : E - 22:26:40 - - : Duration : 2.4 +/- 0.4 s Mid-event : 22:24:15.6 +/- 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: 600 ms 7 OBSERVING CONDITIONS: Atmospheric transparency: fair Wind: no Temperature: 15 deg C Star image stability: fair Minor planet visible: yes 8 ADDITIONAL COMMENTS: Analyzed using Tangra v3.7.4 and AOTA v4.2022.7.24 S/N of occulted star: 5.7 - 5.6 (AOTA) Camera temperature: -20 deg C Observed magnitude drop: 0.5 m (AOTA) Applied approximate recording delay: 29 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) IBEROC feed (2022/06/17): Event time: 22:24:16 UT Error in time: 3 s Max duration: 3.7 s Star magnitude: 14.7 m Asteroid magnitude: 14.1 m Combined magnitude: 13.6 m Magnitude drop: 0.5 m Position: In the 1-sigma zone, 32 km outside the shadow path Probability: 21.1 %