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A 4.56 second occultation was recorded by Dave Herald, using video OSD technique.
A reappearance only was observed by Ivan Curtis using Drift Scan tecnique but unforuneately missed the Disappearance.
View the updated prediction.
Observers: 1 D Herald,Kambah, ACT,AU 2 I Curtis,Vale Park, Adelaide, SA,AU 3(M) D Gault,Hawkesbury Heights,NSW,AU 4(M) S Quirk,Mudgee,NSW,AU 5(P) Prediction 19 Nov IOTA
Discussion:
The circle above is plotted at the expected 137 km diameter of Aurelia.
The constraint of Dave Gault's miss forces the fit to be rather poor.
If an ellipse as below is drawn with axis ratio set to maxcimum 1.28 predicted from
light curve data it tends to force the size down but a reasonable fit can be obtained.
With 1 and half chords and nearby miss we can be fairly confident of the path of Aurelia and that it was south of the predicted line.
The figure below shows Dave Herald's Tangra light curve of the occultation.
Observational Data:
Observation details for MP (419) Aurelia By Star UCAC2 38755148 On 2011-01-08 at 12:53:35.0 _______________________________ Observer Ivan Curtis/Tina Curtis Location Vale Park, Adelaide, SA,AU Longitude +138:37 Latitude -34:53 Altitude 44 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 24 cm Seeing Slight flickering Broken cloud Camera Type Camera Delay Timing other Drift scan Disappearance not measured Reappearance 12:53:37.00 Comments: Disappearance was already under way at the beginning of drift exposure, which was started at 12:53:34 +/- 0.5s Timing was extracted from FITS image header of drift image. Imaging PC is running Windows XP, and was synced to internet time server prior to image capture. FITS header has time to resolution of 1 second. _______________________________ Observer Dave Gault Location Hawkesbury Heights,NSW,AU Longitude +150:38 Latitude -33:39 Altitude 286 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 20 cm Seeing Steady Thick cloud > 2 Camera Type Camera Delay Timing GPS - time inserted Video with frame analysis Missed Comments: Clouded at 12:51:18 - exactly one minute before predicted time. No event up till this time Cleared at 12:52:39 - No event seen until… Clouded at 12:53:10 - remained clouded thereafter _______________________________ Observer Steve Quirk Location Mudgee,NSW,AU Longitude +149:39 Latitude -32:27 Altitude 508 m Datum Telescope Newtonian Aperture 32 cm Seeing Slight flickering Clear Camera Type Camera Delay Timing GPS - time inserted Video with frame analysis Missed Comments: no drop seen in Limovie graph _______________________________ 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 Slight flickering Clear Camera Type Camera Delay Timing GPS - time inserted Video with frame analysis Disappearance 12:52:26.71 Reappearance 12:52:31.27 Comments: Report prepopulated by IOTA Reporting Add-in for OW ver.1.5