ASTEROIDAL OCCULTATION - REPORT FORM +--------------------------------+ +----------------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +--------------------------------+ +----------------------------------------+ 1 DATE: 30 October 2021 STAR: UCAC4 441-119766 ASTEROID: (20765) 2000 JC40 2 OBSERVERS: Name : Wojciech Burzynski Abrr: BZY Address : 15-345 Bialystok, Poland 3 OBSERVING STATION: Nearest city : Suprasl Station : Lipowy Most Acc. Latitude : 53 12 31.5 N - 0.1" Longitude : 23 31 37.9 E - 0.1" Altitude : 145 MSL - 1 m Datum (WGS84 preferred): WGS84 Single, OR Double or Multiple station (Specify observer's name): single 4 TIMING OF EVENTS: +----------------------------------------------+ | OCCULTATION RECORDED: POSITIVE | +----------------------------------------------+ Type of event: "S"tart observation "I"nterrupt-start "D"isappearance "B"link "F"lash "E"nd observation "J"nterrupt-end "R"eappearance "O"ther (specify) Event Time (UT) P.E. Acc. Code HH MM SS.ss S.ss S.ss S - 18:42:46 D - 18:43:45.18 +/- 0.05 R - 18:43:45.63 +/- 0.05 E - 18:44:30 Duration: 0.45 s +/- 0.07 (AOTA) Calculated mag drop: 1.3 mag Predicted max. duration (secs) : 0.5 Predicted max. drop (mag) : 4.5 Predicted mid-event (UT) : 18:43:45 Predicted error in time : 2 sec Was your reaction time applied to the above timings? - not relevant 5 TELESCOPE: Type : NEW f/4.7 Aperture : 254 mm Focal length: 1195 mm FOV : 32.37' x 20.23' Mount : equatorial GOTO Motor drive: yes 6 TIMING & RECORDING: Time source : GPS 1PPS Sensor : QHY 174M GPS Mode of recording: 1920x1200, 12 bit FITS, bin 2x2, Gain=480 Mode of recording: Contrast=0, Brightness=0, Gamma=1, USB traffic=50 Shutter : 0.100 s Recording : Laptop Dell Latitiude 3540 (Intel Core i5/RAM 16 GB/SSD 480 GB) Recording : SharpCap 4.0.8264 7 OBSERVING CONDITIONS: Atmospheric transparency : good Wind (m/s) : 5 Temperature (deg C / humid.) : 3 / 80 Star image stability : good Minor planet visible : no Local conditions (degree) : star altitude: 29, sun altitude: -34 Local moon conditions (degree) : moon altitude: below horizon 8 ADDITIONAL COMMENTS: Observed star : UCAC4 441-119766 Star magnitude (mag) : 12.5 Minor planet magnitude (mag) : 17.0 Feed : UKOCL, last updated Oct 09, 2021 Rank : 38 Distance (km) : in the 1-sigma zone, 4 km outside the shadow path (12 km to the central line) Shadow width (km) : 15 Predicted probability OccultWatcher (%) : 20.4 Predicted combined magnitude (mag) : 12.5 Faintest star on movie (mag) : 13.5 Evaluation with Tangra 3.7.3 and AOTA 9 REMARKS: Observed drop of 1.3 mag less than expected 4.5 mag.