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(19810) Partridge occults UCAC4 484-051174

Watec 910 video camera
IOTA-VTI GPS time inserter
OccuRec (recording)
Tangra and AOTA (reduction)
The mag 18.6 asteroid (19810) Partridge, 9 km in diameter, was predicted to occult a mag 12.1 Kepler2 star in Leo on 2019 April 12. Observers within the 12 km wide shadow track could see a brief drop in brightness of 6 magnitudes for up to 1s.
My site was 51 km outside the predicted track with a 3.9% probability of success. I was delighted to record a dip in brightness of 0.96s as the asteroid occulted the star. The attached plot shows the analysis of the light curve using Tangra and AOTA.
D - 22 07 16.83 ± 0.04
R - 22 07 17.79 ± 0.04
I must have been very close to the centre line of the asteroid's shadow. The mid-time of the occultation and the Gaia position of the target star will give high-precision astrometry of the asteroid.
Compensation for having missed some recent high probability events due to cloudy nights.