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Four positive chords and 3 misses were recorded for this event.
View the updated prediction.
Observers: 1(M) J Bradshaw,Samford,QLD,AU 2 J Broughton,Reedy Creek, QLD,AU 3 J Broughton,Chinderah, NSW 4 D Herald,Yass,NSW,AU 5 P Purcell,Murrumbateman, NSW,AU 6(C) A Brakel,3.1 km N of Gundaroo, NSW,AU 7(M) D Herald,Kambah, ACT,AU 8(P) Prediction 21 July
Discussion:
The ellipse above is plotted at the best fit to the 4 observed chords. This gives a slightly smaller area than the predicted circle of 76 km. With 4 chords we can be confident of the path of Leopoldina and that it was North-East of the predicted line. The Light Curve Database gives a maximum axis ratio of about 1.38 which is in good agreement with the measured value of 1.32.
The figures below show the drift-scan image of the occultation together and the data as analysed by John's Scanalyser software.
The figure below shows the light curve of the occultation as seen by Patrick Purcell - he was clouded on either side but had a lucky break during the event.
Observational Data:
Observation details for MP (893) Leopoldina By Star TYC 5270-01385-1 On 2010-08-30 at 14:27:44.0 _______________________________ Observer John Broughton Location Chinderah, NSW Longitude +153:33 Latitude -28:15 Altitude 5 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 25 cm Seeing Steady Broken cloud Timing GPS - time inserted Video with frame analysis Disappearance 14:27:53.80 Reappearance 14:28:01.70 Comments: Watec 120N+ at 8x integration. _______________________________ Observer Dave Herald Location Yass,NSW,AU Longitude +148:57 Latitude -34:52 Altitude 525 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 20 cm Seeing Slight flickering Broken cloud Timing GPS - time inserted Video with frame analysis Disappearance 14:29:07.22 Reappearance 14:29:14.84 Comments: Cloud was a problem, but the light curve came through.... Report prepopulated by IOTA Reporting Add-in for OW ver.1.5 _______________________________ Observer Jonathan Bradshaw Location Samford,QLD,AU Longitude +152:50 Latitude -27:22 Altitude 80 m Datum WGS84 Telescope Newtonian Aperture 36 cm Seeing Steady Clear Timing GPS - time inserted Video with frame analysis Missed Comments: Report prepopulated by IOTA Reporting Add-in for OW ver.1.4 _______________________________ Observer Dave Herald Location Kambah, ACT,AU Longitude +149:03 Latitude -35:23 Altitude 582 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 35 cm Seeing Steady Clear Timing GPS - time inserted Video with frame analysis Missed Comments: Report prepopulated by IOTA Reporting Add-in for OW ver.1.5 _______________________________ Observer Patrick Purcell Location Murrumbateman, NSW,AU Longitude +148:59 Latitude -34:57 Altitude 608 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 20 cm Seeing Strong flickering Broken cloud Timing GPS - time inserted Video with frame analysis Disappearance 14:29:08.13 Reappearance 14:29:15.29 Comments: Clouds: intruded just prior to 14h 26m UT. Intermittent clearing fortunately included a 'window' for about 30 seconds at exactly the right time. The light curve shows a definite drop in brightness at a time when the brightness should have peaked as the cloud cleared briefly. I have attached the light curve. How lucky was this? Clouds obscured the field just a few minutes before the predicted event. Fortuitously the cloud thinned out at the critical time permitting this light curve from Murrumbateman. I think I have used up all my good luck for the next decade! _______________________________ Observer Albert Brakel Location 23.1 km N of Gundaroo, NSW,AU Longitude +149:14 Latitude -34:49 Altitude 619 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 20 cm Seeing Slight flickering Thin cloud < 2 Timing Tape Recorder + time signal Visual, no PE applied Missed (clouded) Comments: A mag 11 star in moonlight was always going to be difficult visually (but possible), but thin cirrus wisps forming in the region at the critical time caused the star to be invisible at the predicted time. For what it's worth, the star was just visible from 14:28:06 to 14:29:09, and then for very brief glimpses at 14:29:41 and 14:30:09. The lat/long of the site is that given by a car GPS. _______________________________ Observer John Broughton Location Reedy Creek, QLD,AU Longitude +153:23 Latitude -28:06 Altitude 66 m Datum WGS84 Telescope Newtonian Aperture 51 cm Seeing Steady Clear Timing other Drift scan Disappearance 14:27:56.95 Reappearance 14:27:59.94 Comments: Unattended drift scan.