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OCCULTATION OF TYC 6251-00476-1 BY 1211 Bressole
2015 August 4

A 3 second occultation was observed visually by Rob Horvat at Glenbrook, New South Wales. Negative observations were reported by Dave Gault observing with an ADVS system at Hawkesbury Heights in New South Wales and by Chad Ellington in Kent, Washington, USA using a conventional video system.

View the IOTA update..

  1(M) C Ellington,Burlington, WA           
  2(M) D Gault,Kuriwa Observatory, NSW, AU  
  3      Horvat,Glenbrook, NSW, AU          
  4(P) Prediction


Bressole occultation__ 2015 August 4


The circle above is plotted at the expected 43 km diameter of Bressole. With two negative observations so close to both the north and south of Rob's observed chord, it is hard to reconcile an intepretation of this observation. The star is bright as seen through a 30cm scope (v mag = 10.2) and while the moon was also bright, it was not close to the field.This is an unusual obseravtion in that the observers are spaced along way apart with Chad Ellington observing from the west coast of the USA. It is possible (although unlikely) that (1211) Bressole would have significantly rotated between the times of the events observed on each side of the Pacific presenting a different profile to each observer. Even though, it is had to come to any conclusion other than that Bressole is much smaller than predicted and/or of a very irregular outline.

Observational Data:

Observation details for MP ( 1211 ) Bressole
By Star              TYC 6251-00476-1 
On 2015-08-04  at 08:01:37.0


Observer   Chad K Ellington
Location   Burlington, WA
Longitude  -122:19
Latitude   +48:27
Altitude   11 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   25 cm
Seeing     Strong flickering Thin cloud < 2 
Camera Type  PC164C         NTSC/EIA      
Camera Delay 
Timing     GPS - time inserted Video, photo or photoelectric


Comments: Did not notice anything live besides flickering. Video analysis confirms this…no event. 
 Report prepopulated by IOTA Reporting Add-in for OW ver.1.8


Observer   Dave Gault
Location   Kuriwa Observatory, NSW, AU
Longitude  +150:38
Latitude   -33:39
Altitude   286 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   30 cm
Seeing     Slight flickering Clear 
Camera Type  Flea 3-03S1 with ADVS        ADVS          
Camera Delay 
Timing     GPS - time inserted Video with frame analysis




Observer   Rob Horvat
Location   Glenbrook, NSW, AU
Longitude  +150:37
Latitude   -33:46
Altitude   199 m
Datum      WGS84
Telescope Newtonian
Aperture   30 cm
Seeing     Steady 
Camera Type  Visual         
Camera Delay 
Timing     NTP Servers via iPhone app
Disappearance  08:24:09.20
Reappearance   08:24:12.20

iPhone app used with time from NTP servers.
Some cloud about to the west but seemed to be clear to the east where the target star was.


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