A 3.13 second occultation was recorded by John Broughton at Reedy Creek, Qld, Australia, using the CCD drift-scan technique.

View the updated prediction.

Observers:
  1 J. Broughton, Reedy Creek, QLD, Australia   
  2 Pedicted 

Discussion:

The circle above is plotted at the expected 106km diameter of Corduba. With only one chord it is not possible to determine whether John was north or south of the central line of the event. However, assuming the updated prediction was approximately correct would suggest that the chord might lie across the southern portion of the asteroid as shown.

The figures below shows the drift-scan image of the occultation together with data as analysed by John's Scanalyser software.

Observational Data:

Observer's Name                  : John Broughton
Aperture (cm)                    : 51
Focal length (cm)                : 138
Type (e.g. SCT; Newtonian)       : F/2.7 Astrograph 
Magnification                    : CCD drift-scan at 4.2 pps, 60'FOV 
Observing site name              : Reedy Creek, Gold Coast
Longitude (East +ve)             : +153 23' 49"
Latitude (South -ve)             : -28 06' 36"
Height above Sealevel (metres)   : 66
Geodetic Datum (e.g.WDD84,NZ1949): AGD66
Sky Transparency (Delete two)    : Good
Star Image Stability (Delete two): Good
Other Conditions:                  
     (Wind, Clouds, Lights, etc.): 18 degrees from a half moon
                              
Time Source (e.g. WWV, VNG)      : WWVH.
Recording method (e.g. tape)     : Tape.  
Could you see the Asteroid?      : Only combined light monitored.
Approx. Limiting Magnitude       : 14.5
                                          | Estimated  |
                           Universal Time | Reaction   | Accuracy, Remarks
                              h  m  s     | Time (sec) | 
Started Observing          : 18:04:53.80       n/a       0.01
Disappearance At           : 18:05:17.02       n/a       0.05
Reappearance At            : 18:05:20.15       n/a       0.05
Stopped Observing          : 18:05:26.06       n/a       0.01
Duration                   :        3.14    

ADDITIONAL COMMENTS:  
Rigorously timed CCD drift-scan measured in Scanalyzer:
http://www.users.bigpond.com/reedycrk/driftscantiming.htm

There's a faint overlapping trail ending 1 second after the D.
Another faint trail begins 2 seconds after the R. I conclude that
the non-symetry of the D and R is entirely due to these factors
and the step in R does not represent a companion star.  

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