A 14.8 second occultation was recorded by Brian Loader, using video OSD technique.
No clearly observed misses were recorded for this event.
View the updated prediction.
Observers: 1 B Loader,Darfield 2(P) Prediction.Personal April 24
The circle above is plotted at the expected 230 km diameter of Fortuna. With only one chord it is not possible to determine whether Brian was north or south of the central line of the event. The Damit 3D model has been overlaid on the measured circle.
The figure below shows the Limovie/Tangra light curve of the occultation.
The noise level in this curve is quite high but the measured chord could fit the DAMIT model with an offset of +/- 50 km so it must be considered as at very least a "probable" positive. With the DAMIT and Tangra estimate of probability together I think this can with confidence be treated as a Positive observation.
Observation details for MP ( 19 ) Fortuna By Star UCAC4 390-060062 On 2015-04-24 at 11:50:31.0 _______________________________ Observer B. Loader Location Darfield Longitude +172:06 Latitude -43:28 Altitude 210 m Datum WGS84 Telescope SCT including Cass and Mak Aperture 25 cm Seeing Slight flickering Thin cloud < 2 Camera Type WAT910BD AAV-PAL Camera Delay -0.04 Timing GPS - time inserted Video with frame analysis Disappearance 11:50:14.19 Reappearance 11:50:28.99 Comments: Occult Prediction: combined mag 10.7, expected d mag 0.06 (5%), Event T max 17.2 sec, Pred time error 6s, Prob of event 83% Tangra: signal only used, normalised with comparison star, x8 binning applied.