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Updated: 2007 JUL 21, 17:14 UT
Event Rank : 59
(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 Aug 16 UT, the 46 km diameter asteroid (482) Petrina will occult a 11.9 mag star in the constellation Scutum for observers along a path passing near Exmouth, Carnarvon and Shark Bay in Western Australia.
In the case of an occultation, the combined light of the asteroid and the star will drop by 1.6 mag to 13.2 mag (the magnitude of the asteroid) for at most 5.7 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 Limit1 Path Limit2 Error Limit1 Error Limit2
E. Longitude Latitude U.T. Alt Az Alt
o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " o ' " o ' " o ' " o ' "
Longitude Latitude Longitude Latitude Longitude Latitude Longitude Latitude
115 42 2 -18 26 53 16 51 48 40 280 -81 116 1 47 -18 31 36 115 22 27 -18 22 9 116 44 8 -18 41 34 114 41 25 -18 12 6
115 19 23 -19 20 38 16 52 1 40 281 -81 115 39 10 -19 25 22 114 59 44 -19 15 52 116 21 40 -19 35 24 114 18 34 -19 5 45
114 57 39 -20 14 33 16 52 14 40 282 -81 115 17 32 -20 19 19 114 37 56 -20 9 46 116 0 11 -20 29 25 113 56 36 -19 59 35
114 36 52 -21 8 40 16 52 27 40 283 -80 114 56 50 -21 13 28 114 17 3 -21 3 51 115 39 42 -21 23 37 113 35 32 -20 53 36
114 17 1 -22 2 59 16 52 40 40 284 -80 114 37 5 -22 7 49 113 57 6 -21 58 8 115 20 11 -22 18 2 113 15 22 -21 47 50
113 58 6 -22 57 33 16 52 53 40 285 -79 114 18 17 -23 2 25 113 38 3 -22 52 40 115 1 38 -23 12 42 112 56 4 -22 42 18
113 40 7 -23 52 21 16 53 6 40 286 -78 114 0 27 -23 57 15 113 19 56 -23 47 26 114 44 5 -24 7 36 112 37 41 -23 37 0
113 23 4 -24 47 25 16 53 18 40 286 -78 113 43 34 -24 52 21 113 2 45 -24 42 29 114 27 32 -25 2 47 112 20 11 -24 31 58
113 7 0 -25 42 47 16 53 31 40 287 -77 113 27 39 -25 47 45 112 46 30 -25 37 48 114 11 59 -25 58 15 112 3 35 -25 27 13
112 51 53 -26 38 27 16 53 44 40 288 -76 113 12 43 -26 43 27 112 31 13 -26 33 26 113 57 28 -26 54 2 111 47 55 -26 22 46
112 37 46 -27 34 27 16 53 57 40 289 -75 112 58 49 -27 39 29 112 16 54 -27 29 23 113 44 0 -27 50 8 111 33 12 -27 18 39
112 24 41 -28 30 47 16 54 10 40 290 -75 112 45 56 -28 35 52 112 3 35 -28 25 42 113 31 37 -28 46 36 111 19 26 -28 14 52
112 12 38 -29 27 30 16 54 23 40 291 -74 112 34 8 -29 32 38 111 51 18 -29 22 23 113 20 20 -29 43 27 111 6 39 -29 11 28
112 1 40 -30 24 38 16 54 36 39 292 -73 112 23 27 -30 29 47 111 40 5 -30 19 27 113 10 13 -30 40 42 110 54 54 -30 8 27
111 51 51 -31 22 10 16 54 48 39 292 -72 112 13 54 -31 27 22 111 29 58 -31 16 57 113 1 18 -31 38 23 110 44 12 -31 5 51
111 43 11 -32 20 9 16 55 1 39 293 -71 112 5 34 -32 25 25 111 21 1 -32 14 54 112 53 39 -32 36 30 110 34 37 -32 3 42
111 35 47 -33 18 38 16 55 14 38 294 -70 111 58 29 -33 23 55 111 13 16 -33 13 19 112 47 19 -33 35 7 110 26 11 -33 2 2
111 29 40 -34 17 36 16 55 27 38 295 -69 111 52 45 -34 22 57 111 6 47 -34 12 15 112 42 23 -34 34 15 110 18 58 -34 0 51
111 24 56 -35 17 7 16 55 40 38 295 -68 111 48 25 -35 22 31 111 1 40 -35 11 43 112 38 57 -35 33 56 110 13 2 -35 0 12
111 21 40 -36 17 13 16 55 53 37 296 -67 111 45 36 -36 22 40 110 57 59 -36 11 45 112 37 5 -36 34 11 110 8 28 -36 0 8
111 19 59 -37 17 55 16 56 6 37 297 -66 111 44 23 -37 23 25 110 55 49 -37 12 23 112 36 55 -37 35 3 110 5 21 -37 0 39
111 19 59 -38 19 15 16 56 18 36 297 -65 111 44 54 -38 24 49 110 55 19 -38 13 41 112 38 35 -38 36 35 110 3 48 -38 1 49
111 21 49 -39 21 18 16 56 31 36 298 -64 111 47 18 -39 26 55 110 56 35 -39 15 39 112 42 14 -39 38 48 110 3 56 -39 3 40
111 25 38 -40 24 4 16 56 44 35 299 -63 111 51 45 -40 29 45 110 59 48 -40 18 22 112 48 3 -40 41 46 110 5 54 -40 6 14
111 31 38 -41 27 37 16 56 57 34 299 -62 111 58 25 -41 33 22 111 5 7 -41 21 51 112 56 14 -41 45 31 110 9 52 -41 9 35
Use these links for further information:
[Planetary Occultations]
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[Observing Details]
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