ASTEROIDAL OCCULTATION - REPORT FORM +------------------------------+ +------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +------------------------------+ +------------------------------+ 1 DATE: 2021/10/02 STAR: TYC 1721-00561-1 ASTEROID: (17839) 1998 HN95 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: NEGATIVE | | | +----------------------------+ 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 - 23:21:11 - - : E - 23:24:28 - - : 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 Sensor: ZWO ASI174MM-C Recording: ZWO ASICAP V2.3 Exposure: 10 ms 7 OBSERVING CONDITIONS: Atmospheric transparency: fair Wind: Temperature: 8 deg C Star image stability: fair Minor planet visible: no 8 ADDITIONAL COMMENTS: Analyzed using Tangra v3.7.3 S/N of occulted star: 3.5 - 6 (Tangra) IBEROC feed (2021/08/26): Event time: 23:22:43 UT Error in time: 4 s Max duration: 1.9 s Star magnitude: 10.2 m Asteroid magnitude: 16.3 m Combined magnitude: 10.2 m Magnitude drop: 6.1 m Position: In the 1-sigma zone, 13 km outside the shadow path Probability: 21.0 %