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Updated: 2015 OCT 08, 21:29 UT
Event Rank : 96
(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 2015 Nov 25 UT, the 70 km diameter asteroid (760) Massinga will occult a 9.0 mag star in the constellation Pisces for observers along a path across north-west WA, passing near Derby and Shark Bay.
In the case of an occultation, the combined light of the asteroid and the star will drop by 4.6 mag to 13.6 mag (the magnitude of the asteroid) for at most 6.4 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
110 20 31 -30 0 0 11 50 48 30 29 -7 109 47 33 110 53 30 109 20 31 111 20 34
111 26 2 -29 0 0 11 50 41 31 28 -8 110 53 21 111 58 45 110 26 33 112 25 36
112 31 10 -28 0 0 11 50 33 32 27 -9 111 58 44 113 3 38 111 32 9 113 30 17
113 35 59 -27 0 0 11 50 25 34 27 -11 113 3 45 114 8 14 112 37 22 114 34 42
114 40 32 -26 0 0 11 50 16 35 26 -12 114 8 31 115 12 35 113 42 17 115 38 54
115 44 54 -25 0 0 11 50 8 36 25 -13 115 13 4 116 16 47 114 46 59 116 42 57
116 49 9 -24 0 0 11 49 58 38 24 -15 116 17 28 117 20 52 115 51 31 117 46 56
117 53 20 -23 0 0 11 49 49 39 24 -16 117 21 47 118 24 56 116 55 57 118 50 53
118 57 32 -22 0 0 11 49 39 40 23 -17 118 26 6 119 29 1 118 0 21 119 54 54
120 1 48 -21 0 0 11 49 29 42 22 -19 119 30 27 120 33 12 119 4 47 120 59 0
121 6 11 -20 0 0 11 49 19 43 21 -20 120 34 55 121 37 32 120 9 19 122 3 17
122 10 46 -19 0 0 11 49 9 44 20 -21 121 39 33 122 42 4 121 13 59 123 7 48
123 15 36 -18 0 0 11 48 58 45 19 -23 122 44 24 123 46 53 122 18 52 124 12 36
124 20 46 -17 0 0 11 48 47 47 18 -24 123 49 34 124 52 2 123 24 2 125 17 45
125 26 17 -16 0 0 11 48 35 48 17 -25 124 55 5 125 57 36 124 29 33 126 23 20
126 32 16 -15 0 0 11 48 23 49 16 -27 126 1 1 127 3 37 125 35 27 127 29 23
127 38 45 -14 0 0 11 48 11 50 15 -28 127 7 26 128 10 10 126 41 49 128 36 0
128 45 48 -13 0 0 11 47 59 52 14 -30 128 14 24 129 17 19 127 48 44 129 43 13
129 53 30 -12 0 0 11 47 46 53 13 -31 129 22 0 130 25 8 128 56 15 130 51 9
131 1 56 -11 0 0 11 47 34 54 12 -33 130 30 17 131 33 42 130 4 26 131 59 50
132 11 9 -10 0 0 11 47 20 55 10 -34 131 39 21 132 43 5 131 13 22 133 9 22
133 21 15 - 9 0 0 11 47 7 56 9 -35 132 49 16 133 53 23 132 23 8 134 19 50
134 32 19 - 8 0 0 11 46 53 58 7 -37 134 0 7 135 4 40 133 33 49 135 31 18
135 44 26 - 7 0 0 11 46 39 59 5 -38 135 11 59 136 17 3 134 45 29 136 43 54
136 57 43 - 6 0 0 11 46 24 60 3 -40 136 24 59 137 30 37 135 58 16 137 57 42
Uncertainty in time = +/- 3 secs
Prediction of 2015 Oct 9.0
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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