ASTEROIDAL OCCULTATION - REPORT FORM

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

1 DATE:                  2018 April 21 00:31:46  (UTC)

  STAR:                  TYC: 0408-00029-1       mv: 11.6  mag
  ASTEROID:              (130) Elektra	 	 mv: 12.9  mag  (diam. 180.6 km)
                         combined magnitude:     mv: 11.3  mag
                         delta-magnitude:        mv:  1.59 mag

2 OBSERVER: 
  Name:                  Jonas SCHENKER / Abbr: Schenker J Observatory
  E-mail:                jonas.schenker@sunrise.ch
  Address:               Ruetiweg 6, CH-5036 Oberentfelden, Switzerland

3 OBSERVING STATION: 
  Nearest city:          5000 Aarau, Switzerland
  Station:               Sternwarte Schafmatt (IAU Observatory Code: B77)
  Latitude:              N 47° 25' 12.88" (WGS84)
  Longitude:             E 07° 57' 02.95" (WGS84)
  Altitude:              820 m (MSL)      (WGS84)

  Predicted observation: no (located 4 km north-eastern of predicted path)
  Probability:           44.3 %
  
  Single station:        Jonas SCHENKER

                         +----------------------------------+
4 TIMING OF EVENT:       |                                  |
                         |  OCCULTATION RECORDED: POSITIVE  |
                         |                                  |
                         +----------------------------------+
  Type of event:
   S = Start observation I = Interrupt-start   D = Disappearance
   B = Blink             F = Flash             E = End observation
   I = Interrupt-end     R = Reappearance      
   M = Mid-event         P = Predicted time

  Event  Time (UTC)      Acc.         Comments
  Code   HH MM SS.sss    S.sss
  
   S     00 26 58        +/-0.020 s : Start observation (UTC)
   D     00 31 46.6976   +/-0.020 s : Disappearance     (UTC)
   R     00 32 01.4575   +/-0.020 s : Reappearance      (UTC)
   E     00 37 02        +/-0.020 s : End observation   (UTC)

   Duration:   14.7599 s +/-0.020 s : (predicted: max. 20.5 s)

   M     00 31 54.0776 	 +/-0.020 s : Mid-event         (UTC)
   P     00 31 46	 +/-2.000 s : Predicted time    (UTC)
        
5 TELESCOPE: 
  Type:                  Cassegrain Astrograph (LOMO / P. Keller)
  Aperture:              450 mm      
  Focal length:          1500 mm f/3.3 (primary focus) 
  Magnification:         focal (resulting field of view: 14.8' x 11.8')
  Mount:                 equatorial
  Motor drive:           yes

6 TIMING & RECORDING:
  Time source:           GPS unit: US Global Sat EM-406A (internal)
  Sensor:                1/2" Watec 910HX-RC (CCIR) (6.47 x 4.83 mm)
                         752 x 582 px (8.6 x 8.3 my) 
  Frame Grabber:         Hauppauge Analog Video Digitizer USB-Live 2
  Time  insertion:       Video Time Inserter IOTA-VTI v3 with GPS
			 Video frame time (Vt)

7 OBSERVING CONDITIONS:
  Atmospheric transp.:   clear
  Wind:                  2.0   m/s
  Temperature:           +17   °C
  Relative humidity:     45    %
  Atmosph. pressure:     2020  hPa
  Moonlight:             no    (moon below horizon during occultation)
  Star image stability:  good  (occulted star 38° above horizon)
  Minor planet visible:  yes   (fainter than occulted star)

8 ADDITIONAL COMMENTS:    
  Shutter mode:                1/50 s (integration x1) 
  Integration time (It)  =    0.020 s
  Correction time  (Ct)  =   -0.020 s (evaluation in frames)
  Tolerance value        = +/-0.020 s (evaluation in frames)
  Video frame time       =    Vt
  Reported event time    =    Vt + Ct (correction time applied) 
  Video editing software:     VirtualDub v1.10.4
  Light measurement tool:     Tangra v3.5.0

  No evidence of any satellite was found in the range of +/- 2 minutes.

9 CREDITS:
  Sepp Kaeser for helpful assistance.