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A 13 second occultation was recorded by john Broughton, using video OSD technique.
View the updated prediction.
Observers: 1 J Broughton,Reedy Creek, QLD,AU 2(P) Prediction, 16 Sept
Discussion:
The circle above is plotted at the expected 87 km diameter of Ludmilla. With only one chord it is not possible to determine whether John was north or south of the central line of the event.
The figure below shows the Limovie light curve of the occultation.
Observational Data:
Observation details for MP (675 ) Ludmilla By Star UCAC2 28103901 On 2009-09-24 at 13:19:44.0 _______________________________ Observer J Broughton Location Reedy Creek, QLD, Australia Longitude +153:23:52.9 Latitude -28:06:30.4 Altitude 66 m Datum WGS84 Telescope SCT Aperture 25 cm Seeing Strong flickering Clear Timing GPS - time inserted Video with frame analysis Disappearance 13:20:10.50 Reappearance 13:20:33.50 Comments: Watec 120N+ running at 8-frame integration. This lengthy 13th-magnitude occultation was a difficult one to analyse. I called it positive initially on the basis there was a noticeable drop in light when running the tape on the VCR in 7x picture-search mode lasting 23 seconds. Limovie reveals an intensity drop from 1900 to 1000 units. Due to the event being 38 seconds late, the plot ends shortly after reappearance when the drift-through target was approaching the edge of the frame. A plot from after the target was shifted shows an intensity level of 1900 and supports the conclusion that R did occur a few seconds before the shift. Noise levels however make the exact position for reappearance somewhat debatable.