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A 58.9 second occultation was recorded by William Hanna, using video OSD technique.
and a 17.9 second event was recorded by Steve Kerr, using Video OSD technique.
Five clearly observed misses were recorded for this event.
View the Special 2MASS prediction.
Observers: 1 W Hanna,Alice Springs, NT,AU 2 S Kerr,Rockhampton,QLD,AU 3(M) J Bradshaw,Samford Valley, Qld, AU 4(M) J Broughton,Reedy Creek, QLD, AU 5(M) D Herald,Murrumbateman, NSW, AU 6(M) J Talbot,Waikanae Beach, NZ 7(M) B Loader,Darfield,NZ 8(P) Prediction, 11 May
Discussion:
The circle above is plotted at the expected 1186 km diameter of Charon. However, assuming the updated prediction was approximately correct the slightly longer than expected chord would suggest that the chord might lie close to the central portion of the asteroid. With 2 chords, and constraining misses, we can be confident of the path of Charon and that it was north of the predicted line.
The figure below shows William's Limovie light curve of the occultation and confirms the expected magnitude drop of 0.6 was seen.
The figure below shows Steve's Limovie light curve of the occultation.
The figure below shows Jonathan's Limovie light curve of the occultation.
This shows an interesting 1 sample dip just before frame 2200 that
is at a time that is consistent with the other two. However as his path
is about 450 km south of the edge of the circle is seems unlikley to be
a graze. Other possibilities are a small cloud, noise spike, piece of Earth orbit space junk, or could it be
another Pluto moonlet or satellite of Charon, or ... !?
Observational Data:
Observation details for MP ( 9 ) Charon By Star 2MASS 18312044-19262 = UCAC3 142-319429 On 2012-07-27 at 14:38:07.0 _______________________________ 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 Strong flickering Clear Camera Type WAT120N PAL/CCIR Camera Delay 0.65 Timing GPS - time inserted Video with frame analysis Missed Comments: spells of very poor seeing Report prepopulated by IOTA Reporting Add-in for OW ver.1.6 _______________________________ Observer William Hanna Location Alice Springs, Australia Longitude +133:53 Latitude -23:42 Altitude 586 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 20 cm Seeing Slight flickering Clear Camera Type WAT120N+ PAL/CCIR Camera Delay 1.31 Timing GPS - time inserted Video with frame analysis Disappearance 14:39:36.00 Reappearance 14:40:32.32 Comments: ~50% moon ~46 degrees below. Light wind. _______________________________ 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 1.31 Timing GPS - time inserted Video with frame analysis Missed Comments: Clear, calm, almost frost, No event Using WATEC borrowed form Terry Butt. _______________________________ Observer Dave Herald Location Murrumbateman, NSW, AU Longitude +148:59 Latitude -34:57 Altitude 594 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 40 cm Seeing Steady Clear Camera Type WAT120N PAL/CCIR Camera Delay 0.33 Timing GPS - time inserted Video with frame analysis Missed Comments: Report prepopulated by IOTA Reporting Add-in for OW ver.1.6 _______________________________ 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 0.65 Timing GPS - time inserted Video with frame analysis Missed Comments: _______________________________ Observer Jonathan Bradshaw Location Samford Valley, Qld, Australia Longitude +152:50 Latitude -27:22 Altitude 80 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 36 cm Seeing Steady Thin cloud < 2 Camera Type G-Star PAL/CCIR Camera Delay 0.26 Timing GPS - time inserted Video with frame analysis Missed Comments: Based on other observations, a miss, but the video did reveal a tantalising ‘blip’ from 14:38:56.292 until 14:38:57.892 (1.6 seconds) which may represent a 30km + object, but probably nothing more than occultation shaped noise. If New Horizons crashes into an unknown rock, I reserve the right to say ‘I told you so’ :) ______________________________ Observer John Broughton Location Reedy Creek, QLD, AU Longitude +153:23 Latitude -28:06 Altitude 66 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 25 cm Seeing Strong flickering Clear Camera Type WAT120N PAL/CCIR Camera Delay 0.33 Timing GPS - time inserted Video with frame analysis Missed Comments: DVR problems caused gap in observation.