A 9 second occultation was recorded by Tony Barry, using an SCT Telescope and Grasshopper Express camera. A subsequent single frame extinction was also recorded.

A 4 second occultation was recorded by Dave Gault, using an SCT Telescope and Watec 910BD camera. A subsequent single frame extinction was also recorded.

View the IOTA update.

Observers:
  1    T Barry,Penrith, Sydney, New South Wales, Australia     
  2    T Barry,Penrith, Sydney, New South Wales, Australia     
  3    D Gault,Hawkesbury Heights, New South Wales, Australia  
  4    D Gault,Hawkesbury Heights, New South Wales, Australia  
  5(P) Prediction
       

Discussion:

The ellipse above is plotted at the expected diameter(s) of Gunila. The model has been plotted to fit the observed chords. The event appears to have been slightly north of the predicted path.

The subsequent extinctions, recorded by both observers, suggest a ring or satellite may be present.

The figures below show the Tangra light curve of the occultation.

Barry:

Gault:

Observational Data:

Observation details for MP ( 983 ) Gunila
By Star              UCAC4 375-80174
On 2017-08-13  at 11:30:35.0

_______________________________

Observer   Tony Barry
Location   Penrith, Sydney
Longitude  +150:43
Latitude   -33:44
Altitude   52 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   25 cm
Seeing     Steady Clear 
Camera Type  Grasshopper Express with ADVS              ADVS          
Camera Delay 
Timing     GPS - time inserted Video, photo or photoelectric
Disappearance  11:30:54.33
Reappearance   11:31:03.66
Comments: Clear skies. Light curve shows a singular frame extinction 7 sec after reappearance.
Report prepopulated by IOTA Reporting Add-in for OW ver.1.8

_______________________________

Observer   Dave Gault
Location   Hawkesbury Heights, NSW, AU
Longitude  +150:38
Latitude   -33:39
Altitude   286 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   30 cm
Seeing     Steady Clear 
Camera Type  Watec 910BD    PAL/CCIR      
Camera Delay 
Timing     GPS - time inserted Video with frame analysis
Disappearance  11:30:56.26
Reappearance   11:30:59.94
Comments:  Lightcurve from 11:30:30 to 11:31:14 by Tangra v3.6.7 using
AperturePhotometry/AverageBackground. Analysis by AOTA v4.3.2.0.
Report prepopulated by IOTA Reporting Add-in for OW ver.1.8