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A 14 second occultation was recorded by Steve Kerr, using video OSD technique.
No clearly observed misses were recorded for this event.
View the TT14 prediction.
Observers: 1 S Kerr,Rockhampton,QLD,AU 2(P) Prediction, TT14 29 Aug
Discussion:
As Steve's chord was much longer than expected maximum, the ellipse above is plotted with major
axis fitting the chord and the minor axis at the size expected for a circular object.
Both previous observations had chords of about 86 km.
One of these had two greatly differing chords suggested that this was an elongated object.
With only one chord it is not possible to determine whether Steve was north
or south of the central line of the event.
However, assuming the prediction was approximately correct the longer
than expected chord of about 118 km would suggest that the chord might lie
close to the central portion of the asteroid.
It also suggests that Croatia may be a much darker than predicted object with lower albedo.
There are no DAMIT or ISAM 3D models for Croatia yet.
The figure below shows the Tangra light curve of the occultation.
Observational Data:
Observation details for MP ( 589 ) Croatia By Star UCAC4 390-109182 On 2013-09-18 at 10:33:14.0 _______________________________ Observer S. Kerr Location Rockhampton,QLD,AU Longitude +150:30 Latitude -23:16 Altitude 50 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 30 cm Seeing Slight flickering Clear Camera Type WAT120N+ PAL/CCIR Camera Delay -0.11 Timing GPS - time inserted Video with frame analysis Disappearance 10:32:57.39 Reappearance 10:33:11.47 Comments: Report prepopulated by IOTA Reporting Add-in for OW ver.1.7