ASTEROIDAL OCCULTATION - REPORT FORM

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

1 DATE: 20 October 2022             STAR:  UCAC4 389-132219 (15.0 mag)
  ASTEROID: Arachne                   No: 407 (13.8 mag.)

2 OBSERVER: Name: Marek Zawilski            Abbr:
            E-mail: marek.zawilski@p.lodz.pl
            Address: ul.Julianowska 5/7 m.322, 91-473 Lodz, Poland
            Assistance: Mieczyslaw Borkowski

3 OBSERVING STATION: Nearest cities: Lodz and Poddebice
  Station: Tobolice
  Latitude:  51d 54' 46.0" N
  Longitude: 19d 03' 21.4" E
  Altitude:  147 m 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  - 18:18:11      - N/A  1.0   
    D  - 18:19:42.8           0.4     AOTA analysis
    R  - 18:19:53.2           0.6     AOTA analysis
    E  - 18:22:01      - N/A  1.0    
 
                          Duration : 10.4 s
                         Mid-event : 20 Oct;20:19:48.0 UT
               Predicted mid-event : 20 Oct;20:19:48 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 9 satellites).
  Sensor: ZWO ASI 120MM, shutter set for 850 ms, video time resolution 850 ms, image resolution 640x480 px, gain 80, brightness 15.
  Recording: SHARPCAP v.4.0.8949.0 software.

7 OBSERVING CONDITIONS:
  Atmospheric transparency: good           Wind: none            Temperature: 1 deg C
  Star image stability: good           Minor planet visible: yes

8 ADDITIONAL COMMENTS:
 
  The light curve analyze using Tangra software showed a distinct drop of the star brightness caused by the asteroid.  
  The observation was made inside the predicted path. 


  Predicted max. 8.5 sec. duration with 0.3 mag. drop.
  Event probability at site : 100%
  Distance from center line : 22.4 km in 148° direction, inside the predicted path.
  Local * conditions (Alt,Az): 25°, @192° in Aquarius.
  Moon (Alt, Az): below the horizon