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Updated: 2008 JUL 22, 22:48 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 Jul 27 UT, the 229 km diameter asteroid (324) Bamberga will occult a 5.1 mag star, ξ Lupi, in the constellation Lupus for observers along a very wide path across Western Australia and Northern Territory during late afternoon. The path begins near Albany, runs over Kalgoorlie, central Western Australia, then into Northern Territory, passing over Katherine and Darwin.
In the case of an occultation, the combined light of the asteroid and the star will drop by 6.4 mag to 11.5 mag (the magnitude of the asteroid) for as long as 40.1 seconds. Note that the star is double and it will be the brighter component that will be occulted.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, historical astrometry from the MPC files (via AstDys), and the following catalogs for the star position: .
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
133 48 20 - 6 0 0 8 35 58 50 138 6 135 4 1 132 31 22 135 45 53 131 47 41 -0.67
133 22 45 - 8 0 0 8 35 20 51 136 6 134 39 19 132 4 51 135 21 39 131 20 35 -0.67
132 53 36 -10 0 0 8 34 41 52 134 6 134 11 14 131 34 33 134 54 8 130 49 37 -0.68
132 20 36 -12 0 0 8 34 1 53 132 6 133 39 31 131 0 12 134 23 6 130 14 28 -0.68
131 43 27 -14 0 0 8 33 21 53 129 6 133 3 51 130 21 26 133 48 14 129 34 45 -0.69
131 1 45 -16 0 0 8 32 39 54 127 6 132 23 54 129 37 52 133 9 13 128 50 4 -0.69
130 15 3 -18 0 0 8 31 57 54 124 6 131 39 15 128 48 58 132 25 38 127 59 52 -0.70
129 22 49 -20 0 0 8 31 13 55 121 6 130 49 23 127 54 10 131 37 2 127 3 32 -0.70
128 24 23 -22 0 0 8 30 29 55 118 7 129 53 43 126 52 44 130 42 49 126 0 18 -0.71
127 18 57 -24 0 0 8 29 44 54 116 7 128 51 31 125 43 45 129 42 19 124 49 11 -0.72
Latitude Latitude Latitude Latitude
125 0 0 -27 36 12 8 28 21 54 111 7 -29 54 24 -25 9 23 -31 8 35 -23 42 38 -0.73
123 0 0 -30 11 3 8 27 19 53 108 8 -32 17 38 -27 57 54 -33 26 1 -26 39 58 -0.73
121 0 0 -32 23 34 8 26 24 51 106 9 -34 21 7 -30 20 47 -35 24 56 -29 9 25 -0.74
119 0 0 -34 18 15 8 25 35 50 104 9 -36 8 35 -32 23 38 -37 8 42 -31 17 19 -0.74
117 0 0 -35 58 18 8 24 51 49 103 10 -37 42 44 -34 10 15 -38 39 47 -33 7 59 -0.74
115 0 0 -37 26 2 8 24 10 47 102 11 -39 5 34 -35 43 24 -40 0 4 -34 44 25 -0.74
113 0 0 -38 43 15 8 23 33 46 102 11 -40 18 39 -37 5 7 -41 11 0 -36 8 52 -0.75
111 0 0 -39 51 19 8 22 59 45 102 12 -41 23 14 -38 16 59 -42 13 44 -37 23 1 -0.75
109 0 0 -40 51 19 8 22 27 43 102 13 -42 20 15 -39 20 13 -43 9 12 -38 28 10 -0.75
107 0 0 -41 44 9 8 21 58 42 102 13 -43 10 32 -40 15 47 -43 58 7 -39 25 23 -0.75
Uncertainty in time = +/- 12 secs
[Prediction of 2008 Jul 22.0]
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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