A 26.5 second occultation was recorded by Steve Kerr, using video OSD technique. Six other stations were registered but were clouded out.

View the updated prediction.

Observers:
  1    S Kerr,Glenlee, QLD, AU
  2(P) Prediction 27 Dec 2009

    

Discussion:

The circle above is plotted at the expected 547 km diameter of Vesta. With only one chord it is not possible to determine whether Steve was north or south of the central line of the event. However, assuming the updated prediction was approximately correct and given that Vesta was one of the earliest MPs to be tracked so its path is very well known, I have plotted the most probable view for this picture.

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

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

Note that Vesta was more than 3 magnitudes brighter than the star, so the predicted magnitude drop was only 0.04m, and Occular has estimated it at 0.06m. It is fair to say that this was a difficult curve to analyse and two separate analyses were required using different background settings to get this view and error estimates of +/- 0.9 secs were applied.

Observational Data:

Observation details for MP (4) Vesta
By Star              TYC 1423-00836-1
On 2010-02-10  at 17:08:30.0

_______________________________

Observer   Stephen Kerr
Location   Glenlee, QLD, AU
Longitude  +150:30:0.8
Latitude   -23:16:9.6
Altitude   50 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   30 cm
Seeing     Slight flickering Thin cloud < 2
Timing     GPS - time inserted Video with frame analysis
Disappearance  17:08:09.53
Reappearance   17:08:36.02
Comments: Occular time estimates