A 2.3 second occultation was recorded by Murray Forbes, using Video OSD technique.
Two clearly observed misses were recorded for this event.
View the updated prediction.
Observers: 1(M) G McKay,Blenheim, NZ 2(M) B Allen,Blenheim, NZ 3 M Forbes,Lower Hutt, NZ 4(P) Prediction, 24 Feb
The ellipse above is plotted with major axis at 71 km and area the same as
expected diameter of 54 km. The resulting axis ratio of 1.73 is much greater
than the estimated ratio of 1.14 as determined by lightcurve data.
This suggests that the size of Oceana has been significantly under estimated
and that an eqivalent diameter of at least 66 km might be closer to reality.
With only one chord it is not possible to determine whether Murray was north or south of the central line of the event. However, assuming the updated prediction was approximately correct the longer than expected chord of about 71km would suggest that the chord might lie close to the central portion of the asteroid.
The figure below shows the Limovie light curve of the occultation.
Observation details for MP (224) Oceana By Star TYC 6898-01810-1 On 2012-03-17 at 17:45:49.0 _______________________________ Observer Murray Forbes Location Lower Hutt, NZ Longitude +174:58 Latitude -41:09 Altitude 26 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 20 cm Seeing Slight flickering Broken cloud Camera Type KTC530 PAL/CCIR Camera Delay 0 Timing GPS - time inserted Video with frame analysis Disappearance 17:45:54.60 Reappearance 17:45:56.88 Comments: With the camera adjusted to maximum gain, star could be just seen although if the event had been ten minutes later the star would have been lost in the brightening twilight. Nevertheless, the occultation was clearly seen. However the star was very difficult to see on the recording during the subsequent Limovie analysis, hence the larger than normal uncertainties in the D and R. _______________________________ Observer Bill Allen Location Blenheim, NZ Longitude +173:50 Latitude -41:29 Altitude 38 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 40 cm Seeing Slight flickering Clear Camera Type Camera Delay Timing GPS - time inserted Video with frame analysis Missed Comments: Datum NZ1949 (topographical map) Good observing conditions air mass 1.5 Video with GPS _______________________________ Observer Graeme McKay Location Blenheim, NZ Longitude +173:57 Latitude -41:32 Altitude 18 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 20 cm Seeing Steady Clear Camera Type WAT120N PAL/CCIR Camera Delay 0.05 Timing GPS - time inserted Video with frame analysis Missed Comments: Observed a miss Report prepopulated by IOTA Reporting Add-in for OW ver.1.6