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A 3.9 second occultation was recorded by John Broughton, using CCD drift scan technique.
View the updated prediction.
Observers: 1 J Broughton,Reedy Creek, QLD 4227, AU 2(P) Prediction 25 July
Discussion:
The circle above is plotted at the expected 140 km diameter of Melpomene. 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 a compund drift-scan image - See comments below.
Observational Data:
Observation details for MP (18 ) Melpomene By Star UCAC2 30028442 On 2008-08-21 at 08:19:45.0 _______________________________ Observer J Broughton Location Reedy Creek,Reedy Creek, QLD 4227, Australia Longitude +153:23:52.8 Latitude -28:06:30.3 Altitude 66 m Datum WGS84 Telescope Newtonian Aperture 51 cm Seeing Steady Broken cloud Timing Tape Recorder + time signal + shutter Drift scan Disappearance 08:19:46.80 Reappearance 08:19:50.70 COMMENTS: This small 0.36-magnitude drop event was imaged through cloud. To demonstrate what's going on, I compiled an image of 5 aligned trails. In the original image, the top trail was located NW of the occulted trail, the bottom one SE and all trails were scattered in that general direction in the same order as the aligned image. In the aligned image, attenuations caused by cloud move toward the right going from top to bottom and the right-hand ones fade out. The occultation trail (4th from top) bucks the trend near in its centre in a way expected for a positive event. The places I measured D and R in that 4th trail are indicated by arrows and result in a 3.9s duration - plausibly 70% of the maximum predicted.