ASTEROIDAL OCCULTATION - REPORT FORM

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

 1 DATE: 23 July 2021                              STAR: UCAC4 333-177365

  ASTEROID: Levitan                                No: 3566

 2 OBSERVER : 
  Name      : Anna Marciniak, Iga Mieczkowska, Patrycja Pozniak, Julia Perla, Justyna Olszewska        
  Address   : Astronomical Observatory Institute, A. Mickiewicz University, Sloneczna 36, Poznan, Poland

 3 OBSERVING STATION: 
  Nearest city : Poznan
  Station      : Borowiec          IAU obs code: 187
  Latitude     : 52 16 36.8 N   
  Longitude    : 17 04 30.8 E   
  Altitude     : 123 MSL

  Datum (WGS84 preferred): WGS84

  Single, OR Double or Multiple station (Specify observer's name): single

 4 TIMING OF EVENTS:  
  +----------------------------------------------+
  |       OCCULTATION RECORDED: UNCERTAIN        |
  +----------------------------------------------+
  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  - 23:24:35.49   -    - 0.01
  D  - 23:27:15.24   -    - 0.50
  R  - 23:27:16.66   -    - 0.50
  E  - 23:28:17.72   -    - 0.01 
 
                         Duration :   1.42 s +/- 0.90 s
                         Mid-event :  23:27:15.95 +/- 0.50 s
  
  Was your reaction time applied to the above timings? - not applicable.
  
 5 TELESCOPE: 
  Type        : Newton  f/4.5                          Aperture   : 400 mm
  Focal length: 1800 mm                                FOV        : 27'x 30'
  Mount       : paralactic                             Motor drive: no

 6 TIMING & RECORDING:
  Time source      : Local ntp server vega.cbk.poznan.pl (NTP++)
  Sensor           : Andor Zyla 5.5 camera with sCMOS sensor
  Mode of recording: Binning 2x2, Image size: Full
  Shutter (SENS-UP): Electronic
  Recording        : Personal Computer
  Recording        : Own software
  Time insertion   : Embedded by camera into FITS header

 7 OBSERVING CONDITIONS: 
  Atmospheric transparency          : moderate 
  Wind  (km/h)                      : none
  Temperature (deg C / humid.)      : +20 deg C / humidity: high
  Star image stability              : good
  Minor planet visible              : no
  Local conditions (degree)         : star height: 10, Sun height: -18
  Local moon conditions (degree)    : Moon height: 12

 8 ADDITIONAL COMMENTS:
  Star magnitude                          : 11.1
  Minor planet magnitude                  : 17.00
  Feed                                    : IBEROC
  Distance (km)                           : -1.7 km
  Faintest star on CCD (mag)              : 12.7
  Exposure time				  : 0.7 s 
  Readout time				  : 0.01 s

  Predicted max. duration (secs) :  1.61 
  Predicted max. drop (mag)      :  5.9
  Predicted mid-event (UT)       : 23:27:14
  Predicted error in time (secs) :  2
  Probability			 : 90 %

 Remarks: Telescope tracking temporarily out of order. The target drifted into the field 
 of view just 3 frames before the event start. 

 Star seems to be gone on three images, but there is still some residual signal in two of these images.

 Data re-analysis Dr.-Ing. Christian Weber:
 Event analysed with PyOTE gives a false-positive warning.
 Analysis with AOTA gives the same result for timings with slightly smaller uncertainties.