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OCCULTATION OF UCAC2_21883922 BY 91 Aegina
2011 July 27


Five positive chords were recorded for this event. There were no misses or clouded outs. This must be a some sort of record.

View the updated prediction.

Observers:
  1    J Bradshaw,Samford Valley, QLD,AU
  2    P Anderson,THE GAP,Brisbane,QLD,AU
  3    D Lowe,Gatton, Queensland,Australia
  4    J Broughton,Oxenford, QLD, AU
  5    J Broughton,Reedy Creek, QLD, AU
  6(P) Prediction, Jul 22

    

Aegina occultation - 2011 July 27

Discussion:

The ellipse above is plotted at the best fit to the data of 5 chords. This gives an area about 5 percent greater than a circle of the expected diameter of 109 km.
With 5 chords we can be confident of the path of Aegina and that it was just south of the predicted line and within a second of the predicted time.
An excellent result for the team.

The figures below show the light curves of the occultation.

Aegina occultation - 2011 July 27
J Bradshaw

Aegina occultation - 2011 July 27
D Lowe

Observational Data:

Observation details for MP ( 91 ) Aegina
By Star              UCAC2 21883922
On 2011-07-27  at 10:06:39.0

_______________________________

Observer   Dennis Lowe
Location   Gatton, Queensland,Australia
Longitude  +152:21
Latitude   -27:30
Altitude   97 m
Datum      WGS84
Telescope Refractor
Aperture   10 cm
Seeing     Slight flickering Clear
Camera Type  Other integrating            PAL/CCIR
Camera Delay 0.17
Timing     GPS - time inserted Video with frame analysis
Disappearance  10:06:40.98
Reappearance   10:06:47.38
Comments: WAT120N+ camera used.

_______________________________

Observer   Jonathan Bradshaw
Location   Samford Valley, QLD,AU
Longitude  +152:50
Latitude   -27:22
Altitude   80 m
Datum      WGS84
Telescope Newtonian
Aperture   36 cm
Seeing     Steady Clear
Camera Type  G-Star         PAL/CCIR
Camera Delay 0.06
Timing     GPS - time inserted Video with frame analysis
Disappearance  10:06:39.97
Reappearance   10:06:42.11
Comments: Short, clear event in good conditions. Much as predicted.
GSTAR 2x (1 frame) = -20ms delay, -20ms mid point, +- 20ms accuracy

_______________________________

Observer   Peter Anderson
Location   THE GAP,Brisbane,QLD,AU
Longitude  +152:55
Latitude   -27:27
Altitude   170 m
Datum      WGS84
Telescope Newtonian
Aperture   41 cm
Seeing     Slight flickering Clear
Camera Type
Camera Delay
Timing     Tape Recorder + time signal Visual, PE applied
Disappearance  10:06:39.00  -0.3
Reappearance   10:06:43.00  -0.3
Comments: Star and asteroid easily visible.
Monitoring started and when event occurred one stopwatch was fumbled
and the other failed.
I had a tape recorder with WWVH and 'beeper' but had called out a two or three
word comment each time (tsk tsk) so the accuracy suffered.
One stopwatch failed and the other I mistriggered - only discovered later.
Results were extracted from tape comments
Though I have 39.0 to 43.0s, I could be talked into 38.8 to 42.8s because
I was concentrating on the stopwatches and not the tape.
[For the record I subtracted 0.3 secs from Peter' times to get a best fit to
the video observations.  jt]
_______________________________

Observer   John Broughton
Location   Oxenford, QLD, AU
Longitude  +153:19
Latitude   -27:52
Altitude   2 m
Datum      WGS84
Telescope Newtonian
Aperture   32 cm
Seeing     Slight flickering Clear
Camera Type  WAT120N        PAL/CCIR
Camera Delay 0.05
Timing     GPS - other linking Video with frame analysis
Disappearance  10:06:33.73
Reappearance   10:06:41.89
Comments:

_______________________________

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     Slight flickering Clear
Camera Type  WAT120N        PAL/CCIR
Camera Delay 0.05
Timing     GPS - time inserted Video with frame analysis
Disappearance  10:06:33.25
Reappearance   10:06:41.25
Comments:


    

Return to 2011 occultation results



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