ASTEROIDAL OCCULTATION - REPORT FORM +------------------------------+ +------------------------------+ | EAON | | IOTA/ES | | | | INTERNATIONAL OCCULTATION | | EUROPEAN ASTEROIDAL | | TIMING ASSOCIATION | | OCCULTATION NETWORK | | EUROPEAN SECTION | +------------------------------+ +------------------------------+ 1 DATE: 12 March 2022 STAR: UCAC4 499-033071 (12.9 mag) ASTEROID: Arequipa No: 737 2 OBSERVER: Name: Marek Zawilski Abbr: E-mail: marek.zawilski@p.lodz.pl Address: ul.Julianowska 5/7 m.322, 91-473 Lodz, Poland Assitance: Mieczyslaw Borkowski 3 OBSERVING STATION: Nearest cities: Lodz Station: Ksawerow Latitude: 51d 40' 55.8" N Longitude: 19d 22' 52.3" E Altitude: 188m MSL 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 Start observation Interrupt-start Disappearance Blink Flash End observation Jnterrupt-end Reappearance Other (specify) Comments Event Time (UT) P.E. Acc. Code HH:MM:SS.ss S.ss S.ss S - 20:32:00 - N/A 1.0 D - 20:32:40.65 0.06 AOTA analysis R - 20:32:47.67 0.12 AOTA analysis E - 20:33:25 - N/A 1.0 Duration : 7.02 sec Mid-event : 20:32:44.16 Predicted mid-event : 12 Mar;20:32:42 UT +/- 4 sec Was your reaction time applied to the above timings? N/A 5 TELESCOPE: Type: Cassegrain Aperture: 203mm Magnification: --- Mount: Equatorial Motor drive: YES Foc.length: 2032mm reduced to 1016mm 6 TIMING & RECORDING: Time source: Laptop time controlled by the GPS Shelyak TimeBox device (time error +0.000 s with 9 satellites). Sensor: ZWO ASI 120MM, shutter set for 120 ms, video time resolution 120 ms, image resolution 1024x768 px, gain 50, brightness +12. Recording: SHARPCAP v.4.0.8667.0 software. 7 OBSERVING CONDITIONS: Atmospheric transparency: very good Wind: none Temperature: -4 deg C Star image stability: good Minor planet visible: no 8 ADDITIONAL COMMENTS: The light curve analyze using Tangra software and a careful inspection of the screen replay showed a clearly remarkable drop of the star brightness caused by the asteroid. The star image was stable both for the occulted and a guiding star. The D and R times according to the AOTA analysis. Predicted max.6.4 sec. duration with 1.8-2.0 mag. drop. Event probability at site : 67% Distance from center line : -1.5 km, inside the predicted path. Local * conditions (Alt,Az): 40°, @225° in Monoceros. Moon (Alt, Az): 58°, @228°, did not disturb the observation.