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Two occultations were recorded by John Broughton, One using CCD drift scan with a prepointed telescope and the other with a mobile unit using visual technique.
View the updated prediction.
Observers: 1(M) D Watson,Thornton near Whakatane,NZ 2 J. Broughton, Sleepy Hollow, QLD, AU 3 J. Broughton, Reedy Creek, QLD, AU 4(M) P Anderson,Taylor Range Observatory,QLD, AU 5(M) J Bradshaw,ord, Queensland, AU 6(P) Prediction 22 July
Discussion:
With two chords we can be confident that John's Reedy Creek location was north of the centerline of the event. The ellipse above is plotted at the best fit to John's observations of Hohensteina with the extra constraint that the ellipse axes have a ratio of no more than 1.09 as suggested by published parameters. This is less than this data suggests, however the published is flagged as Provisional and this plot is within the error bars so has good agreement. The misses by the rest of the team are consistent with the positive results.
The figures below show the drift-scan image of the occultation together and the data as analysed by John's Scanalyser software.
Observational Data:
Observation details for MP (788) Hohensteina By Star UCAC2 31177691 On 2008-08-04 at 09:11:00.0 _______________________________ Observer Diana Watson Location Thornton near Whakatane Longitude +176:51:50. Latitude -37:55:51. Altitude 3 m Datum Other Telescope SCT including Cass and Mak Aperture 200 cm Seeing Steady Clear Timing Tape Recorder + time signal Visual, no PE applied Missed Comments: _______________________________ Observer John Broughton Location Reedy Creek, QLD,AU Longitude +153:23:52.8 Latitude -28:06:30.3 Altitude 66 m Datum WGS84 Telescope Newtonian Aperture 51 cm Seeing Steady Clear Timing Tape Recorder + time signal + shutter Drift scan Disappearance 09:18:53.16 Reappearance 09:18:57.78 Comments: Unattended drift-scan observation. The trail and occultation is very clear for an event involving a 12.7-magnitude star. _______________________________ Observer John Broughton Location Sleepy Hollow, QLD, AU Longitude +153:31:15.3 Latitude -28:25:22.9 Altitude 20 m Datum WGS84 Telescope SCT Aperture 25 cm Seeing Steady Clear Timing Tape Recorder + time signal Visual, PE applied Disappearance 09:18:53.95 Reappearance 09:18:59.79 Comments: The 13.6-magnitude asteroid was glimpsed during the occultation. _______________________________ Observer Peter Anderson Location Taylor Range Observatory Longitude +152:55:54. Latitude -27:27:48. Altitude 176 m Datum Other Telescope Newtonian Aperture 41 cm Seeing Slight flickering Broken cloud Timing Tape Recorder + time signal Visual, PE applied Missed Comments: I had positively identified the star and was ready but cloud prevented earlier commencement. There were definitely no events. _______________________________ Observer Jonathan Bradshaw Location Samford, Queensland, Australia Longitude +152:52:22.7 Latitude -27:21:22.8 Altitude 95 m Datum WGS84 Telescope Dobsonian Aperture 50 cm Seeing Steady Broken cloud Timing GPS - time inserted Video with frame analysis Missed Comments: Clouded out 10 seconds after the expected event. I did get some re-appearences later on, but my video record is incomplete