Two positive occultations were recorded by John Broughton, using Video OSD technique.

View the updated prediction.

Observers:
  1    J Broughton,Brunswick Heads, NSW,AU
  2    J Broughton,Reedy Creek, QLD,AU
  3(P) Prediction 22 Dec IOTA

    

Discussion: The circle above is plotted at the expected 216 km diameter of Ursula. At least two previous occultation obseravtions with 7 or more chords show Ursula to have a shape that fits an ellipse with axis ratio of about 1.17. The best one measured the size as 220 x 188 km. The ellipse below is plotted at this size and then allowed to find best fit orientation.

With two of chords we can be confident of the path of Ursula and that it was north of the predicted line.

The figure below shows the light curves of the occultation.

Observational Data:

Observation details for MP (375) Ursula
By Star              UCAC2 46793538
On 2011-01-02  at 10:41:14.0

_______________________________

Observer   John Broughton
Location   Brunswick Heads, NSW
Longitude  +153:32
Latitude   -28:33
Altitude   5 m
Datum      WGS84
Telescope Newtonian
Aperture   31 cm
Seeing     Steady Clear
Camera Type
Camera Delay
Timing     GPS - other linking Video with frame analysis
Disappearance  10:40:53.19
Reappearance   10:41:08.55
Comments:

_______________________________

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     Steady Clear
Camera Type
Camera Delay
Timing     GPS - time inserted Video with frame analysis
Disappearance  10:40:54.23
Reappearance   10:41:08.95
Comments: