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A 5.06 second occultation was recorded by Graeme McKay, using Video OSD technique.
Two clearly observed misses were recorded for this event.
View the updated prediction.
Observers: 1(M) J Talbot, Waikanae Beach, NZ 2() G Hudson,Porirua, New Zealand 3 G McKay,Blenheim, New Zealand 4(M) B Loader,Darfield,NZ 5(P) Prediction,27 August
Discussion:
Both John and Gordon had problems: John managed a prepoint and had the right field but set his intgration too low, and had to resort to gamma correction in Limovie to measure the star. Gordon appears to have been on the wrong field despite careful alignment with 2 other stars. The ellipse above is plotted at a reasonable fit axis ratio constrained by the DAMIT shape. With only 1 chord the scale may or may not be correct and should not be used to calibrate the DAMIT model for size. With one longer than expected chord and a miss we can be sure that the path slightly north of the predicted line of the event. Assuming the updated prediction was approximately correct, the longer than expected chord of about 80km would suggest that the chord might lie close to the central portion of the asteroid.
The figure below shows the Tangra light curve of Graeme's occultation.
Observational Data:
Observation details for MP ( 441 ) Bathilde By Star UCAC2 25623276 On 2014-09-30 at 09:44:22.0 _______________________________ Observer Graeme McKay Location Blenheim, New Zealand Longitude +173:57 Latitude -41:32 Altitude 18 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 28 cm Seeing Slight flickering Clear Camera Type WAT120N+ PAL/CCIR Camera Delay -0.11 Timing GPS - time inserted Video with frame analysis Disappearance 09:44:18.51 Reappearance 09:44:24.11 Comments: Duration 5.60 sec observed vs predicted max 4.1 sec Report prepopulated by IOTA Reporting Add-in for OW ver.1.8 _______________________________ Observer John Talbot Location Waikanae Beach, NZ Longitude +175:01 Latitude -40:51 Altitude 5 m Datum WGS84 Telescope Newtonian Aperture 25 cm Seeing Slight flickering Clear Camera Type WAT120N+ PAL/CCIR Camera Delay -0.35 Timing GPS - time inserted Video with frame analysis Missed Comments: Star very faint and no dip that could not be noise. Report prepopulated by IOTA Reporting Add-in for OW ver.1.8 _______________________________ Observer B. Loader Location Darfield Longitude +172:06 Latitude -43:28 Altitude 210 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 25 cm Seeing Slight flickering Broken cloud Camera Type WAT910BD AAV-PAL Camera Delay -0.04 Timing GPS - time inserted Video with frame analysis Missed Comments: Thin "coastal" cloud just beginning to move in, patchy effect. Report prepopulated by IOTA Reporting Add-in for OW ver.1.8 _______________________________ Observer G Hudson Location Porirua, New Zealand Longitude +174:50 Latitude -41:06 Altitude 52 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 30 cm Seeing Steady Clear Camera Type WAT120N+ PAL/CCIR Camera Delay -0.67 Timing GPS - time inserted Video with frame analysis Uncertain Comments: May have been on wrong field. We have tried to identify the field but have not been able to. It does not match the C2A view.