A 24.47 second occultation was recorded using the CCD drift-scan technique by John Broughton in Reedy Creek, Queensland..

View the Updated Prediction

Observers:
  1    J. Broughton, Reedy Crk, Australia   
  2(M) D. Gault, Hawkesbury Hts, Australia  

M = Miss

The circle represents the expected 86 km diameter of Lydia.

Drift-scan trace:

Scanalyser Trace:

Discussion:

Another excellent result from John, confirming the value of the CCD drift-scan technique.

Observational Data:

Observer's Name                  : John Broughton
Aperture (cm)                    : 50.1
Focal length (cm)                : 140
Type (e.g. SCT; Newtonian)       : Newtonian 
Magnification                    : CCD drift-scan, 4.3 pixels per second 
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.): None
Time Source (e.g. WWV, VNG)      : WWVH.
Recording method (e.g. tape)     : Drift-scan. Taped shutter and time signal.  
Could you see the Asteroid?      : Only combined light monitored though
                                   asteroid is visible during occultation.
Approx. Limiting Magnitude       : 14
                                          | Estimated  |
                           Universal Time | Reaction   | Accuracy, Remarks
                              h  m  s     | Time (sec) | 
Started Observing          : 09:16:20.61       n/a       0.01
Disappearance At           : 09:17:48.57       n/a       0.06
Reappearance At            : 09:18:13.04       n/a       0.06
Stopped Observing          : 09:19:52.29       n/a       0.01
Duration                   :       24.47   

ADDITIONAL COMMENTS: Being near the eastern edge of the nominal path
I didn't expect to record a near maximum duration so either the path
had shifted in my direction or Lydia is larger than expected.
As the 24 second duration is the longest I have recorded, the measured
timing accuracy represents a distance of only 0.2km at the asteroid.

An explanation of methodology and relevant software is available at:
http://www.users.bigpond.com/reedycrk/driftscantiming.htm 

Observational Data - Occultation Not Seen:

Observer's Name                  : Dave Gault
Aperture (cm)			 : 25
Focal length (cm)		 : 122
Type (e.g. SCT; Newtonian)	 : EQ Newtonian
Magnification			 : PC164C at Newtonian Focus
Observing site name		 : Dave's Skyshed
Longitude (East +ve)		 : 150 38.4637
Latitude (South -ve)		 : -33 39.8663
Height above Sealevel (metres)	 : 286
Datums				 : WGS84 and MSL
Sky Transparency 		 : Fair
Star Image Stability 		 : Fair
Time Source (e.g. WWV, VNG)	 : GPS
Recording method (e.g. tape)	 : KIWI
Could you see the Asteroid?	 : No
Approx. Limiting Magnitude	 : 11.8
				 : UT Time	|  PE	| Accuracy	| Remarks
Started Observing		 : 9:15
Stopped Observing		 : 9:25

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