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A 9.02 second occultation was recorded by Dave Herald at Beacon, WA, Australia, using video and GPS technique.
View the updated prediction.
Observers: 1 D Herald, Beacon, WA, Australia 2 Predicted
Discussion:
The circle above is plotted at the expected 150km diameter of Berbericia. With only one chord it is not possible to determine whether Dave was north or south of the central line of the event. However, assuming the updated prediction was approximately correct would suggest that the chord might lie across the northern portion of the asteroid.
Observational Data:
Observer's Name : D Herald
Aperture (cm) : 20cm
Focal length (cm) : 200cm
Type (e.g. SCT; Newtonian) : SCT
Magnification : -
Observing site name : Beacon, WA
Longitude (DD MM SS ; East +ve) : 117 52 04.1
Latitude (DD MM SS ; South -ve) : -30 26 59.5
Height above Sealevel (metres) : 373
Geodetic Datum (e.g.WGS84,NZ1949): WGS84
Height Datum (if known) : WGS84
Sky Transparency (Delete two) : Good
Star Image Stability (Delete two): Good
Other Conditions:
Time Source (e.g. WWVH, GPS) : GPS
Recording method (e.g. tape) : Video
Could you see the Asteroid? : no
Approx. Limiting Magnitude :
| Estimated |
Universal Time | Reaction | Accuracy, Remarks
h m s | Time (sec) |
Started Observing : 10 10 00
Disappearance At : 10 13 02.42 gradual over 0.08s
Reappearance At : 10 13 11.44 gradual over 0.12s
Stopped Observing : 10 15 00
ADDITIONAL COMMENTS:
I got another successful asteroidal occultation this evening - the 2nd in three nights (with a
close miss on the intermediate night). Duration was 9.02 secs, compared to a predicted max of
15.3secs
The event occured soon after sunset - with a sun altitude of -12deg. I was able to do a two-star
alignment using Antares and Spica fairly soon after sunset, and acquire the mag 8 star some 30
mins before the event. I got excellent signal-to-noise. Interestingly both events were non-
instantaneous.
The D is close to Fresnel diffraction(?). But the R could be affected by stellar diameter.
The star is quite red - Mv=8.71, Mb=9.68.
This is now the third asteroidal I've observed at my daughter's residence in Beacon, Western
Australia. That's about as many as I've observed from home! And the skies here are REALLY dark -
with there being no population centre greater than a few hundred people within 150km to the
south, and >1000km to the north.