ASTEROIDAL OCCULTATION - REPORT FORM

    +------------------------------+  +------------------------------+
    |            EAON              |  |            IOTA/ES           |
    |                              |  |   INTERNATIONAL OCCULTATION  |
    |     EUROPEAN  ASTEROIDAL     |  |      TIMING  ASSOCIATION     |
    |     OCCULTATION NETWORK      |  |       EUROPEAN SECTION       |
    +------------------------------+  +------------------------------+

1 DATE: 11 March 2022             STAR: UCAC4 445-033109  (11.5 mag)
  ASTEROID: Ohio                   No: 439 

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: Rawa Maz. 
  Station: Pukinin
  Latitude:  51d 45' 46.5" N
  Longitude: 20d 17' 03.9" E
  Altitude:  143m 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  - 19:36:00      - N/A  1.0   
    D  - 19:37:01.28          0.09               AOTA analysis
    R  - 19:37:07.71          0.09               AOTA analysis
    E  - 19:37:45      - N/A  1.0    
 
                          Duration : 6.43 sec
                         Mid-event : 19:37:04.50
               Predicted mid-event : 11 Mar;19:37:04 UT  +/- 2 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 8 satellites).
  Sensor: ZWO ASI 120MM, shutter set for 189 ms, video time resolution 189 ms, image resolution 640x480 px, gain 50.
  Recording: SHARPCAP v.4.0.8667.0 software.

7 OBSERVING CONDITIONS:
  Atmospheric transparency: very good     Wind: none            Temperature: -4 deg C
  Star image stability: very good         Minor planet visible: yes

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. The asteroid was visible about 20 min before the event using larger exposure time (>2s).
  

  Predicted max.7.5 sec. duration with 3.5 mag. drop.
  Event probability at site : 93%
  Distance from center line : -0.5 km, inside the predicted path.
  Local * conditions (Alt,Az): 36°, @197° in Monoceros.
  Moon (Alt, Az): 58°, @226°, did not disturb the observation.