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BRIEF SUMMARY:
Total observed chords: 11
This plot has been generated by WinOCCULT and supplied by Dave Herald:
1(M) T. Leyland/A. Baker, St Arnaud, NZ 2(*) M Forbes, Murchison, NZ 3 G. Hudson, Murchison, NZ 4 R. Price, Springhurst, Vic, AU 5 A. Brakel, Bombala, NSW, AU 6 J.L. Sanchez, Argentina (CCD) 7 D. Gault, Wooragee, Vic, AU 8 G. Blow, Matakitaki, NZ 9 S. Buda, Katunga, Vic, AU 10 W. Kissling, Upper Matakitaki, NZ 11 P. Skilton, Boralmo, Vic, AU (Video) 12 J. Blanksby, Lake Rowan, Vic, AU 13 P. Purcell, Delegate, NSW, AU 14(M) L. Hussey, Hudalee, NZ 15(M) J Tillbrook, Clare Valley, SA, AU M = Miss; * = Incorrect star
Australia:
CHORD: 7.7 sec
Observer : Dave Gault
Observing site name : Wooragee
Longitude (East +ve) : 146 44 18.98
Latitude (South -ve) : - 36 17 19.96
Height above Sealevel (metres) : 386
Geodetic Datum : WGD84
: Universal Time | Reaction | Accuracy, Remarks
Disappearance At : 08:45:09.126 : 0.451 : 0.2 :
Reappearance At : 08:45:16.806 : 0.409 : 0.2 :
No PE subtracted.
ADDITIONAL COMMENTS: The sky was very clear and it was very cold despite the time being only 6:45pm
and a heavy dew was starting to form on equipment. By the time I observed the occultation my fingers
were sore and stiff despite keeping my hands in my pockets when I could. I performed two PE tests
on KIWI in the field immediately and the results show an increase in reaction time from my normal
0.35 seconds. The disappearance and reappearances seemed more gradual in the binoculars when
compared to past events observed in the telescope.
CHORD: 7.6 sec
Observer : Albert Brakel
Observing site name : Endeavour Lookout, Bombala
Longitude (East +ve) : +149 14' 58"
Latitude (South -ve) : -36 55' 24"
Height above Sealevel (metres) : 855 m
Geodetic Datum : ???
: Universal Time | Reaction | Accuracy, Remarks
Disappearance At : 8:44:52.8 1.0
Reappearance At : 8:45:00.4 0.0
PE ALREADY SUBTRACTED : D 1.0s, R 0.0s
ADDITIONAL COMMENTS: Both D and R instantaneous. I was expecting
D at around the minute tone, so having the event ~7 sec earlier
took me a bit by surprise, and I've allowed a longer than usual PE
of 1.0 sec. This has been subtracted from the raw timing. R occurred
towards the end of the minute tone, fixing it very closely, so no
PE is relevant. Assuming the minute tone lasted 0.5 sec (as that
of VNG used to do), the time of 8:45:00.4 is accurate to plus or
minus 0.1 sec. There was a microwave tower and transformer close by,
and some static from them was picked up by the radio and tape. This
caused some degradation of recording quality, but I could still
decipher the tape okay. The best WWVH signal (at 15 MHz) was weak,
and the second pips could only just be heard.
CHORD: 7.6 sec
Observer : Patrick Purcell
Observing site name : Delegate, NSW
My preliminary (guesstimate) figure of 6 seconds was very approx.
This afternoon I was able to listen properly to the tape several
times and my observation was of a 7.6 second disappearance with
the reappearance at 8h 45m 0.9s.
For the record my actual times were as follows
Disappearance: UTC 8h 44m 53.6s (estimated to be about 0.5s late) and
Reappearance: UTC 8h 45m 1.3s (0.4s late)
Duration: 7.6 seconds
Observing location:
E 148 degrees 57 minutes 23.8s
S 37 degrees 02 minutes 52.7s
Elevation: ? unknown but same as Delegate (which is fairly flat)
Geodetic Datum: ???
Telescope: 25cm f7 Dobsonian reflector with 35mm Panoptic eyepiece
Time signal: WWVH on 5 MHz- good signal reception with dipole aerial.
I attribute my late times to a bit of fatigue (after driving about
230Km from Canberra to Delegate, a town near the NSW-Vic border)
coupled with some anxiety about correctly identifying the star in the
limited period between the end of astronomical twilight and the event.
I found the star about 8h 34m UTC (some 10 minutes before the event
as it turned out) but at the time I was worried that I might have
either misidentified it or found it too late. The event itself was
quite spectacular and unmistakable.
CHORD: 7.9 sec
Observer : Stefan Buda
Observing site name : Katunga,Victoria (About 50Km North from Shepparton)
Longitude (East +ve) : 145 27' 26"
Latitude (South -ve) : -36 00' 00"
Height above Sealevel (metres) : ~100??
Geodetic Datum : ???
: Universal Time | Reaction | Accuracy, Remarks
Started Observing : 8:43:00.0
Disappearance At : 8:45:16.50
Reappearance At : 8:45:24.40
Stopped Observing : 8:46:00.0
Was your reaction time (also known as Personal Equation) subtracted from
any of the above timings? : NO
CHORD: 8.0 sec Observer : Jim Blanksby Site: Lake Rowan(Australian Datum 1966) -36d 13' 41.7", 145d 58' 00.8" Alt=155M =/-5M Dis. 08:45:12.5 Reapp. 08:45:20.5 giving duration=8.0s PE say 0.3s not subtracted from above.
CHORD: 8.35 sec Observer : Peter Skilton (Video) I was located just off the Hume Highway mid-way between Boralma and Eldorado, and recorded an occultation both visually through my 15cm newtonian at x29, and also via a piggybacked Sony Handycam pointing at the same field of viewing and operating at maximum optical magnification of x18 with normal shutter speed and manual focus. I had thought it was 1-2 magnitudes beyond the sensitivity of the camera, but was wrong in the conditions. From the visual observation and audio tape: Disappearance was at 8:45:09.82 UTC (already corrected for 0.28 sec measured PE). Reappearance was at 8:45:18.17 UTC (already corrected with same PE). Therefore 8.35 sec occultation. Both events were fast. Observing conditions were near perfect locally, aside from icy cold conditions (my thermometer indicated zero C). As a very close approximation, Land Victoria indicates that the site was just in Byawatha at: 36d 15m 54s S 146d 24m 48s E Datum: GDA94. As an experiment, I also tried transferring the audio tape to XP's Microsoft Sound Recorder and playing it back at 8 times slower than normal speed and viewing the sound level graph as a function of time. This enabled very accurate placement of the minute time pip and the start of the words "gone" and "back" as 8:45:09.86 and 8:45:18.14, giving an occultation result of 8.28 sec (both PE corrected, which will be the main uncertainty, but without the additional error incurred by me listening back to the tape recording with stopwatch in hand and trying to get the times as above. The uncertainty in the output from the software is probably 0.02 sec or better, so the main uncertainty will be in the PE. By video: The star at nearly magnitude 6 was very close to the capabilities of my home video camera to detect it, and the excellent observing conditions probably made the difference between seeing it or not seeing it. Looking at the 8mm video frame by frame on my TV/VCR at maximum contrast gave the occultation as 209 +/- 4 frames, therefore 8.36 +/- 0.16 sec. The uncertainty is due to the noise in the recording compared with the star brightness, and it is possible if it could be analysed by someone with suitable frame grabber software and able to average out and subtract off the background noise over several frames, that the uncertainty might be able to be reduced to fewer frames. While the time signal is recorded on the tape, the visual time was not synchronised (my omission) and so giving accurate start and stop times from the video was not possible with my VCR which cannot play the audio of the minute marker in frame-by-frame mode.
CHORD: 7.1 sec
Observer's Name : Robert T. Price
Observing site name : 8 km west of Springhurst
Longitude (East +ve) : 146 d 23' 38"
Latitude (South -ve) : -36 d 08' 32"
Height above Sealevel (metres) : 150 m
: Universal Time | Reaction | Accuracy, Remarks
Disappearance At : 8:45:11.7
Reappearance At : 8:45:18.8
Reaction times ALREADY subtracted: 0.3 (D) 0.3 (R)
New Zealand:
CHORD: 7.8 sec
Observer's Name : Graham Blow
Observing site name : Matakitaki
Longitude (East +ve) : 172 20 15.1
Latitude (South -ve) : -41 58 27.4
Height above Sealevel (metres) : 300
Geodetic Datum (e.g.WGD84,NZ1949): NZ 1949
: Universal Time | Reaction | Accuracy, Remarks
Disappearance At : 08:42:07.4 1.0 sec?
Reappearance At : 08:42:15.2 0.8 sec?
No reaction time applied.
ADDITIONAL COMMENTS:
Late setting up and then farmer approached with only a few minutes to spare. Did not start
observing until just before 08:42 and then I was not very prepared mentally and was caught by
surprise at the event - D reaction time ~1.0 sec? R reaction time ~0.8 sec?
CHORD: 8.3 sec
Observer's Name : Warwick Kissling
Observing site name : Upper Matakitaki
Longitude (East +ve) : 172 21 24.2
Latitude (South -ve) : -42 00 46.4
Height above Sealevel (metres) : 340
Geodetic Datum (e.g.WGD84,NZ1949): NZ1949
: Universal Time | Reaction | Accuracy, Remarks
Disappearance At : 08:42:07.2 1.0 sec?
Reappearance At : 08:42:15.5 0.7 sec?
No reaction time applied.
ADDITIONAL COMMENTS:
The reaction times above are pure guesses really. My feeling is that I 'nailed'
the reappearance more closely than the disappearance, but both timings did seem
to take a while. Probably just my inexperience at doing these events. In any
case, the event was very spectacular, and there was absolutely no doubt when it
occurred. Conditions were perfect, and there was plenty of 'margin' for seeing
the star in hand held 7x50s - unlike in the city, where I definitely would have
used a larger optical aid.
CHORD: 6.8 sec
Observer's Name : Gordon Hudson
Observing site name : Six Mile
Longitude (East +ve) : 172 19 37.8
Latitude (South -ve) : -41 52 59.0
Height above Sealevel (metres) : 200
Geodetic Datum (e.g.WGD84,NZ1949): NZ 1949
: Universal Time | Reaction | Accuracy, Remarks
Disappearance At : 08:42:09.0 0.5 Very accurate
Reappearance At : 08:42:15.8 0.5
No reaction time applied.
Argentina:
