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OCCULTATION OF UCAC2_19485472 BY 494 Virtus
2009 May 10


A 14.20 second occultation was recorded by Jonathan Bradshaw, using video OSD technique.

View the TT14 low magnitude prediction map and path details

Observers:
  1    J Bradshaw,Samford, QLD, AU
  2(P) Prediction TT14 24 April
    

Virtus occultation - 2009 May 10

Discussion:

The circle above is plotted at the expected 85 km diameter of Virtus. With only one chord it is not possible to determine whether Jonathan was was north or south of the central line of the event. However, assuming the updated prediction was approximately correct the measured chord of about 87 km would suggest that the chord might lie close to the central portion of the asteroid.
Note that there was a miss reported for Virtus on 2009 April 21 and another positive just a week after this one on 2009 May 17. Both positives had chords close to 87 km, and were late by about 40 seconds in this case and 30 seconds late subsequently.

The figure below shows the Limovie light curve of the occultation.

Virtus occultation - 2009 May 10

Observational Data:

Observation details for MP (494) Virtus
By Star    UCAC2 19485472
On 2009-05-10  at 19:23:47.0

_______________________________

Observer   Jonathan Bradshaw
Location   Samford, QLD, AU
Longitude  +152:52:22.7
Latitude   -27:21:22.8
Altitude   95 m
Datum      WGS84
Telescope Dobsonian
Aperture   50 cm
Seeing     Slight flickering Clear
Timing     GPS - time inserted Video with frame analysis
Disappearance  19:24:42.62
Reappearance   19:24:56.82
Comments: 55 Seconds late!
Full moon required 12x (6 Frame) integration.
I have subtracted 120ms which is my estimate of the camera lag,
but the margin of error may be as high as +/- 120ms

    

Return to 2009 occultation results



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