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Updated: 2007 DEC 07, 03:08 UT
Event Rank : 98
(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 2007 Dec 11 UT, the 130 km diameter asteroid (187) Lamberta will occult a 11.9 mag star in the constellation Auriga for observers along a broad path across Western Australia from west of Eucla to Learmonth at relatively low elevation.
In the case of an occultation, the combined light of the asteroid and the star will drop by 1.2 mag to 12.6 mag (the magnitude of the asteroid) for at most 9.0 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
136 52 35 -41 0 0 18 2 15 4 329 -12 ... .. .. 135 16 30 ... .. .. 134 6 1
135 54 44 -40 0 0 18 2 16 5 329 -13 137 28 41 134 18 48 ... .. .. 133 8 23
134 55 35 -39 0 0 18 2 18 6 330 -14 136 29 25 133 19 40 ... .. .. 132 9 12
133 55 0 -38 0 0 18 2 19 7 330 -15 135 28 52 132 18 58 ... .. .. 131 8 23
132 52 54 -37 0 0 18 2 22 9 331 -17 134 26 56 131 16 38 135 33 23 130 5 48
131 49 12 -36 0 0 18 2 24 10 332 -18 133 23 31 130 12 33 134 30 7 129 1 22
130 43 45 -35 0 0 18 2 27 11 333 -19 132 18 30 129 6 34 133 25 21 127 54 56
129 36 28 -34 0 0 18 2 31 12 333 -21 131 11 47 127 58 34 132 18 58 126 46 21
128 27 9 -33 0 0 18 2 34 14 334 -22 130 3 13 126 48 24 131 10 51 125 35 26
127 15 41 -32 0 0 18 2 39 15 335 -23 128 52 39 125 35 51 130 0 51 124 21 59
126 1 51 -31 0 0 18 2 44 16 335 -25 127 39 55 124 20 43 128 48 49 123 5 47
124 45 27 -30 0 0 18 2 49 18 336 -26 126 24 50 123 2 45 127 34 34 121 46 32
123 26 13 -29 0 0 18 2 55 19 337 -28 125 7 10 121 41 41 126 17 53 120 23 57
122 3 51 -28 0 0 18 3 1 20 338 -29 123 46 40 120 17 10 124 58 34 118 57 38
120 38 2 -27 0 0 18 3 9 22 339 -31 122 23 2 118 48 47 123 36 19 117 27 6
119 8 21 -26 0 0 18 3 17 23 340 -32 120 55 55 117 16 2 122 10 49 115 51 49
117 34 16 -25 0 0 18 3 25 25 341 -34 119 24 54 115 38 20 120 41 42 114 11 2
115 55 11 -24 0 0 18 3 35 26 342 -36 117 49 27 113 54 53 119 8 31 112 23 52
114 10 18 -23 0 0 18 3 45 27 344 -37 116 8 56 112 4 41 117 30 42 110 29 4
112 18 37 -22 0 0 18 3 57 29 345 -39 114 22 34 110 6 26 115 47 34 108 25 1
110 18 46 -21 0 0 18 4 9 30 347 -41 112 29 18 107 58 15 113 58 14 106 9 17
108 8 52 -20 0 0 18 4 24 32 348 -42 110 27 44 105 37 29 112 1 34 103 38 17
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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