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A 16 second occultation was recorded by Johnathan Bradshaw, using video OSD technique.
View the updated prediction.
Observers:
1 J Bradshaw,Samford,QLD,AU
2(M) J Broughton,Reedy Creek, QLD, AU
3(P) Prediction, 26 July
Discussion:
John had a fairly noisy recording and while there were some interesting dips
none seemed to fit well with Jonathan's chord.
We cannot fit a circle to Jonathan’s chord without crossing John line, so the Plot above
has an ellipse that just fits the chord and makes John's site a graze point.
The ellipse is plotted at the same area as a circle of 184 km and adjusted
to fit Jonathan's chord and treating John's as a grazing miss.
One analysis of John's data using Occular gave a possible dip at about the right time
of only mmagnitude 0.63, about half the expected 0.14
As the star is red giant, with estimated diameter of 0.0001”, a graze could explain a noisy half mag drop.
With just one chord and a nearby miss (or graze) we can be confident of the path of Germania and that it was
south of the predicted line.
The figure below show the light curve of the occultation.
Jonathan Bradshaw's light curve
John Broughton with Occular analysis showing a possible graze event
Observational Data:
Observation details for MP (241) Germania
By Star UCAC3 135-275907
On 2011-07-08 at 10:28:04.0
_______________________________
Observer Jonathan Bradshaw
Location Samford,QLD,AU
Longitude +152:50
Latitude -27:22
Altitude 80 m
Datum WGS84
Telescope Newtonian
Aperture 36 cm
Seeing Steady Clear
Camera Type
Camera Delay
Timing GPS - time inserted Video with frame analysis
Disappearance 10:27:56.11
Reappearance 10:28:12.15
Comments: Personal prediction from John Broughton.
Used 3 frame integration to get a clear signal for a low mag drop event
The clarity of drop I speculate is due to the high senitivity in IR of the
Gstar camera's chip and the corresponding brightness of the star in red.
_______________________________
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 0.33
Timing GPS - time inserted Video with frame analysis
Disappearance 10:27:51.95
Reappearance 10:27:58.35
Comments: Too much noise to be sure of anything.