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Updated: 2008 NOV 13, 23:41 UT
Event Rank : 99
(The event Rank is a measure of the likelihood of observing an event, and is equal to the probability of at least one successful observation by a team of two observers spaced 1/8 path width just inside opposite sides of the predicted path. An event rank of 100 indicates that the prediction is expected to be very accurate).
THE UPDATED PATH
Note: The duration given in the line below is the interval during which the occultation shadow sweeps across the Earth - please see the minute markers on the map to determine the approximate time for your location.
On 2008 Nov 29 UT, the 151 km diameter asteroid (776) Berbericia will occult a 12.3 mag star in the constellation Gemini for observers along a broad path across Australia, from Sydney across north-eastern New South Wales and central Queensland to northern Northern Territory, passing just north of Darwin.
In the case of an occultation, the combined light of the asteroid and the star will drop by 0.5 mag to 11.6 mag (the magnitude of the asteroid) for at most 13.9 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: UCAC.
Additional details of this and other events are available at Steve Preston's website at http://www.asteroidoccultation.com/
EVENT DETAILS SUMMARY :Important Note regarding Accuracy:
The uncertainty interval in path widths given above (and shown as a 1-sigma uncertainty ellipse on the plot) refers to RMS deviation and is applied as a +/- range. In other words, a path uncertainty of 1.0 path widths means that the actual center of the asteroid's shadow path should fall within plus or minus 1 path width of the plotted path center. However path errors larger than 1 sigma have been observed so observers should be alert for primary occultations within plus or minus 3 sigma of the updated path.
Further, almost all asteroidal satellites discovered so far have been found within 10 diameters of the asteroid (since this distance is deep enough within the gravitational well to be stable over long timescales). Therefore, if monitoring for secondary events, observing out to about 10 path-widths either side of the predicted track remains worthwhile.
We therefore recommend that you monitor for events if your observing location is up to +/- 10 path-widths from the predicted track. If not monitoring for occultations by secondary bodies you should observe from locations within 3 sigma of the nominal path.
In terms of time, the predictions are now usually accurate to about +/- 0.3 minute so you should be most attentive during the predicted minute of the event. However if intending to catch a potential satellite occultation you should start observing at least 10 times the predicted central duration before the predicted closest approach time for your location, and continue for a similar period afterwards.
Centre Star Star Sun Path Limits Error Limits
E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4
o ' " o ' " h m s o o o o ' " o ' " o ' " o ' "
Longitude Longitude Longitude Longitude
152 49 22 -35 0 0 15 39 1 28 4 -27 154 8 11 151 29 28 154 58 5 150 37 43
152 10 48 -34 0 0 15 39 8 29 5 -28 153 29 13 150 51 18 154 18 51 149 59 47
151 31 26 -33 0 0 15 39 16 30 6 -29 152 49 29 150 12 15 153 38 54 149 20 57
150 51 13 -32 0 0 15 39 24 31 6 -30 152 8 59 149 32 18 152 58 12 148 41 10
150 10 8 -31 0 0 15 39 32 32 7 -31 151 27 40 148 51 26 152 16 44 148 0 24
149 28 8 -30 0 0 15 39 41 33 8 -32 150 45 31 148 9 35 151 34 27 147 18 39
148 45 13 -29 0 0 15 39 50 33 9 -33 150 2 29 147 26 46 150 51 20 146 35 52
148 1 20 -28 0 0 15 39 59 34 9 -35 149 18 32 146 42 54 150 7 20 145 52 0
147 16 26 -27 0 0 15 40 9 35 10 -36 148 33 39 145 57 58 149 22 26 145 7 1
146 30 30 -26 0 0 15 40 19 36 11 -37 147 47 46 145 11 55 148 36 35 144 20 53
145 43 27 -25 0 0 15 40 29 37 12 -38 147 0 52 144 24 42 147 49 45 143 33 32
144 55 15 -24 0 0 15 40 39 38 13 -39 146 12 52 143 36 15 147 1 51 142 44 55
144 5 51 -23 0 0 15 40 50 39 14 -41 145 23 44 142 46 32 146 12 53 141 54 58
143 15 11 -22 0 0 15 41 1 39 15 -42 144 33 25 141 55 28 145 22 45 141 3 37
142 23 11 -21 0 0 15 41 12 40 16 -43 143 41 50 141 2 59 144 31 24 140 10 47
141 29 46 -20 0 0 15 41 24 41 18 -44 142 48 55 140 9 1 143 38 47 139 16 24
140 34 52 -19 0 0 15 41 36 41 19 -45 141 54 37 139 13 26 142 44 49 138 20 22
139 38 23 -18 0 0 15 41 48 42 20 -47 140 58 49 138 16 11 141 49 25 137 22 34
138 40 13 -17 0 0 15 42 1 43 21 -48 140 1 26 137 17 8 140 52 30 136 22 54
137 40 15 -16 0 0 15 42 14 43 23 -49 139 2 22 136 16 9 139 53 58 135 21 13
136 38 21 -15 0 0 15 42 28 44 24 -51 138 1 30 135 13 7 138 53 42 134 17 22
135 34 24 -14 0 0 15 42 41 44 26 -52 136 58 42 134 7 52 137 51 35 133 11 12
134 28 12 -13 0 0 15 42 55 45 27 -53 135 53 50 133 0 12 136 47 28 132 2 29
133 19 36 -12 0 0 15 43 10 45 29 -54 134 46 43 131 49 55 135 41 14 130 51 2
132 8 22 -11 0 0 15 43 25 45 31 -56 133 37 10 130 36 47 134 32 40 129 36 32
130 54 15 -10 0 0 15 43 40 46 32 -57 132 24 58 129 20 30 133 21 35 128 18 43
129 36 58 - 9 0 0 15 43 56 46 34 -58 131 9 52 128 0 44 132 7 45 126 57 10
128 16 10 - 8 0 0 15 44 13 46 36 -60 129 51 34 126 37 5 130 50 53 125 31 28
Uncertainty in time = +/- 5 secs
[Prediction of 2008 Nov 13.0]
Use these links for further information:
[Planetary Occultations]
[Using the Predictions]
[Observing Details]
[Timing Details]
[Reporting Details]
[Report Form]
[Asteroid Occultation Results]
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