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OCCULTATION OF UCAC4 315_245088 BY 705 Erminia
2014 December 08


Three chords were recorded , using video OSD technique. A short dip , possibly caused by a satellite of about 6 to 10 km, was recorded by Jonathan Bradshaw at a distance of about 400 km from the primary

No clearly observed misses were recorded for this event.

View the TT14 prediction.

Observers:
  1(M) J Bradshaw,Samford Valley, QLD, AU   
  4    D Herald,Murrumbateman, NSW, AU      
  3    D Gault,Kuriwa Observatory, NSW, AU  
  2    T Barry,Werrington Downs, NSW        
  5(P) Prediction, TT14 17 Nov            


        

Erminia occultation__ 2014 December 08

Discussion:

The ellipse above is plotted at the best fit axis ratio as determined by Occult. With 3 chords we can be confident of the path of Erminia and that it was significantly north of the predicted line. The short dip recorded by Jonathan Bradshaw at a distance of about 400 km from the primary may indicate a satellite with a minimum size of about 6 to 10 km.

The figure below shows the Tangra light curve of the Jonathan's short dip.

Erminia occultation__ 2014 December 08 The dip just meets the 3 samples at the bottom criterion that is used as part of the test for a real dip.

The figure below shows the AOTA analysis of the Tangra light curve of Dave Herald's occultation.

Erminia occultation__ 2014 December 08

The figure below shows the Tangra light curve of Dave Gault's occultation.

Erminia occultation__ 2014 December 08

The figure below shows the Tangra light curve of Tony Barry's occultation.

Erminia occultation__ 2014 December 08

The dip is only 2 samples long but aligns well with the the other 2 chords.

Observational Data:


Observation details for MP ( 705 ) Erminia
By Star              UCAC4 315-245088
On 2014-12-08  at 11:11:00.0

_______________________________

Observer   Jonathan Bradshaw
Location   Samford Valley, Qld, Australia
Longitude  +152:50
Latitude   -27:22
Altitude   80 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   36 cm
Seeing     Slight flickering Clear
Camera Type  G-Star         PAL/CCIR
Camera Delay -0.19
Timing     GPS - time inserted Video with frame analysis
Disappearance  11:11:31.43
Reappearance   11:11:31.63
Comments: There was a very short but compelling blip in the light curve that was 
visibly out of the ordinary for scintillation and very much the same magnitude as 
the asteroid. May have been nothing, and I wouldn’t have even bothered if there were
 not some positives to align it with! 

I suspect this may be a Satellite of Erminia [jt]
_______________________________

Observer   Dave Herald
Location   Murrumbateman, NSW, AU
Longitude  +148:59
Latitude   -34:57
Altitude   594 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   40 cm
Seeing     Steady Clear
Camera Type  WAT910BD       PAL/CCIR
Camera Delay -0.06
Timing     GPS - time inserted Video with frame analysis
Disappearance  11:10:55.22
Reappearance   11:10:58.98
Comments:  Lightcurve from 11:10:01 to 11:11:28 by Tangra v3.1.11
 using AperturePhotometry/BackgroundMedian. 
Analysis by AOTA v4.1.3.2. 
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     Steady Clear
Camera Type  Grasshopper Express with ADVS              ADVS
Camera Delay 0
Timing     GPS - time inserted Video with frame analysis
Disappearance  11:11:00.04
Reappearance   11:11:01.78
Comments:  Lightcurve from 11:10:02 to 11:12:19 by Tangra v3.1.13
 using AperturePhotometry/AverageBackground. 
Analysis by AOTA v4.1.3.0. 
Report prepopulated by IOTA Reporting Add-in for OW ver.1.8

_______________________________

Observer   Tony Barry
Location   Werrington Downs, NSW
Longitude  +150:43
Latitude   -33:44
Altitude   66 m
Datum      WGS84
Telescope SCT including Cass and Mak
Aperture   25 cm
Seeing     Steady Clear
Camera Type  Grasshopper Express with ADVS              ADVS
Camera Delay 0
Timing     GPS - time inserted Video with frame analysis
Disappearance  11:11:00.18
Reappearance   11:11:01.24
Comments:  LC file also submitted. 


        

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