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Updated: 2007 SEP 25, 22:40 UT
Event Rank : 26
(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 Oct 03 UT, the 22 km diameter asteroid (876) Scott will occult a 10.4 mag star in the constellation Cetus for observers along a narrow, significant uncertainty path beginning near Geraldton and running across western and northern Western Australia, leaving near Broome.
In the case of an occultation, the combined light of the asteroid and the star will drop by 4.6 mag to 15.0 mag (the magnitude of the asteroid) for at most 2.6 seconds.
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: 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
111 11 19 -34 0 0 20 32 36 46 319 -20 111 0 41 111 21 59 110 6 38 112 16 38
111 48 2 -33 0 0 20 32 22 47 318 -20 111 37 27 111 58 38 110 43 45 112 52 57
112 25 24 -32 0 0 20 32 8 47 317 -20 112 14 52 112 35 56 111 21 28 113 29 58
113 3 25 -31 0 0 20 31 54 48 315 -20 112 52 57 113 13 54 111 59 48 114 7 41
113 42 7 -30 0 0 20 31 40 48 314 -20 113 31 41 113 52 34 112 38 47 114 46 7
114 21 32 -29 0 0 20 31 25 48 312 -20 114 11 8 114 31 56 113 18 25 115 25 18
115 1 40 -28 0 0 20 31 11 49 311 -19 114 51 18 115 12 2 113 58 44 116 5 15
115 42 33 -27 0 0 20 30 56 49 309 -19 115 32 13 115 52 54 114 39 47 116 46 1
116 24 13 -26 0 0 20 30 41 49 308 -19 116 13 54 116 34 33 115 21 33 117 27 35
117 6 42 -25 0 0 20 30 26 49 306 -18 116 56 23 117 17 2 116 4 6 118 10 1
117 50 1 -24 0 0 20 30 11 49 304 -18 117 39 42 118 0 21 116 47 26 118 53 20
118 34 13 -23 0 0 20 29 55 49 303 -18 118 23 54 118 44 33 117 31 37 119 37 34
119 19 19 -22 0 0 20 29 40 49 301 -17 119 9 0 119 29 40 118 16 40 120 22 46
120 5 23 -21 0 0 20 29 24 49 300 -17 119 55 3 120 15 45 119 2 37 121 8 58
120 52 27 -20 0 0 20 29 9 49 298 -16 120 42 5 121 2 51 119 49 31 121 56 13
121 40 34 -19 0 0 20 28 53 49 296 -16 121 30 9 121 50 59 120 37 25 122 44 34
122 29 46 -18 0 0 20 28 37 49 295 -15 122 19 19 122 40 15 121 26 22 123 34 4
123 20 8 -17 0 0 20 28 21 48 293 -15 123 9 37 123 30 40 122 16 24 124 24 47
124 11 43 -16 0 0 20 28 5 48 291 -14 124 1 8 124 22 19 123 7 37 125 16 46
125 4 35 -15 0 0 20 27 48 48 290 -14 124 53 56 125 15 15 124 0 3 126 10 7
125 58 48 -14 0 0 20 27 32 47 288 -13 125 48 4 126 9 34 124 53 46 127 4 53
126 54 28 -13 0 0 20 27 15 47 287 -12 126 43 39 127 5 20 125 48 52 128 1 11
127 51 41 -12 0 0 20 26 59 46 285 -11 127 40 44 128 2 39 126 45 25 128 59 6
128 50 31 -11 0 0 20 26 42 46 284 -11 128 39 27 129 1 37 127 43 31 129 58 45
129 51 7 -10 0 0 20 26 26 45 283 -10 129 39 54 130 2 21 128 43 17 131 0 14
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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