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Updated: 2012 JAN 14, 18:31 UT
Event Rank : 31
(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 2012 Feb 27 UT, the 18 km diameter asteroid (1660) Wood will occult a 10.2 mag star in the constellation Puppis for observers along a path across Western Australia from Jurien Bay to near Port Hedland,
In the case of an occultation, the combined light of the asteroid and the star will drop by 3.8 mag to 14.0 mag (the magnitude of the asteroid) for at most 2.2 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
121 40 3 -10 0 0 12 36 59 77 138 -35 121 45 12 121 34 55 122 7 35 121 12 29
121 26 0 -11 0 0 12 36 45 78 134 -34 121 31 10 121 20 51 121 53 39 120 58 18
121 11 37 -12 0 0 12 36 31 78 129 -34 121 16 48 121 6 25 121 39 24 120 43 47
120 56 51 -13 0 0 12 36 18 78 125 -33 121 2 4 120 51 38 121 24 47 120 28 52
120 41 43 -14 0 0 12 36 4 79 120 -32 120 46 58 120 36 28 121 9 48 120 13 35
120 26 11 -15 0 0 12 35 50 79 114 -32 120 31 27 120 20 54 120 54 26 119 57 52
120 10 13 -16 0 0 12 35 36 79 109 -31 120 15 32 120 4 55 120 38 39 119 41 44
119 53 50 -17 0 0 12 35 22 79 104 -30 119 59 10 119 48 29 120 22 27 119 25 8
119 36 58 -18 0 0 12 35 8 79 99 -30 119 42 21 119 31 35 120 5 47 119 8 4
119 19 37 -19 0 0 12 34 54 79 94 -29 119 25 2 119 14 11 119 48 39 118 50 30
119 1 45 -20 0 0 12 34 40 78 89 -28 119 7 13 118 56 17 119 31 1 118 32 24
118 43 21 -21 0 0 12 34 26 78 84 -28 118 48 51 118 37 50 119 12 52 118 13 45
118 24 22 -22 0 0 12 34 12 77 80 -27 118 29 56 118 18 48 118 54 9 117 54 30
118 4 48 -23 0 0 12 33 58 77 76 -26 118 10 25 117 59 11 118 34 52 117 34 39
117 44 36 -24 0 0 12 33 45 76 73 -26 117 50 16 117 38 55 118 14 57 117 14 9
117 23 43 -25 0 0 12 33 31 76 70 -25 117 29 27 117 17 59 117 54 24 116 52 57
117 2 9 -26 0 0 12 33 17 75 67 -24 117 7 57 116 56 21 117 33 10 116 31 3
116 39 50 -27 0 0 12 33 3 74 64 -23 116 45 42 116 33 58 117 11 12 116 8 22
116 16 44 -28 0 0 12 32 49 73 62 -23 116 22 40 116 10 48 116 48 28 115 44 54
115 52 48 -29 0 0 12 32 35 72 60 -22 115 58 49 115 46 48 116 24 56 115 20 34
115 28 0 -30 0 0 12 32 21 72 58 -21 115 34 5 115 21 55 116 0 33 114 55 20
115 2 16 -31 0 0 12 32 7 71 57 -20 115 8 26 114 56 6 115 35 15 114 29 9
114 35 32 -32 0 0 12 31 53 70 55 -20 114 41 47 114 29 17 115 9 0 114 1 57
114 7 46 -33 0 0 12 31 39 69 54 -19 114 14 7 114 1 25 114 41 44 113 33 40
113 38 52 -34 0 0 12 31 26 68 53 -18 113 45 19 113 32 25 114 13 22 113 4 14
113 8 48 -35 0 0 12 31 12 67 52 -17 113 15 21 113 2 14 113 43 51 112 33 35
Latitude Latitude Latitude Latitude
112 0 0 -37 8 31 12 30 43 65 51 -15 -37 20 39 -36 56 22 -38 13 14 -36 3 0
111 0 0 -38 51 38 12 30 19 63 50 -14 -39 3 15 -38 40 0 -39 53 37 -37 48 57
110 0 0 -40 27 18 12 29 58 61 49 -12 -40 38 27 -40 16 8 -41 26 49 -39 27 10
109 0 0 -41 56 16 12 29 38 60 49 -11 -42 6 59 -41 45 31 -42 53 32 -40 58 26
Uncertainty in time = +/- 5 secs
Prediction of 2012 Jan 15.0
Use these links for further information:
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[Using the Predictions]
[Observing Details]
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