ASTEROIDAL OCCULTATION - REPORT FORM +------------------------------+ +------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +------------------------------+ +------------------------------+ 1 DATE: 2022/05/08 STAR: UCAC4 389-068364 ASTEROID: (1085) Amaryllis 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 - 23:26:02 - - : D - 23:28:49.60 - - 0.20 : R - 23:28:56.40 - - 0.40 : E - 23:32:12 - - : Duration : 6.80 +/- 0.45 s Mid-event : 23:28:53.00 +/- 0.22 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: 400 ms 7 OBSERVING CONDITIONS: Atmospheric transparency: variable Wind: no Temperature: 12 deg C Star image stability: good Minor planet visible: yes 8 ADDITIONAL COMMENTS: Analyzed using Tangra v3.7.4 and AOTA v4.2022.5.11 S/N of occulted star: 5.3 (AOTA) Camera temperature: -10 deg C Applied approximate recording delay: 27 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) UKOCL feed (2022/04/13): Event time: 23:28:53 UT Error in time: 3 s Max duration: 6.7 s Star magnitude: 13.7 m Asteroid magnitude: 14.5 m Combined magnitude: 13.3 m Magnitude drop: 1.2 m Position: In the shadow, 11 km from the central line Probability: 99.4 %