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Updated: 2016 MAY 05, 01:14 UT
Event Rank : 67
(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 2016 Jun 29 UT, the 66 km diameter asteroid (516) Amherstia will occult a 12.4 mag star in the constellation Norma for observers along a path across Western Australia from Esperence to west of Broome.
In the case of an occultation, the combined light of the asteroid and the star will drop by 0.26 mag to 11.00 mag (the magnitude of the asteroid) for at most 10.8 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, astrometry for the asteroid kindly provided by Bill Owen, astrometry for the asteroid kindly provided by the IAU Minor Planet Center.
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 Alt
E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 Crn
o ' " o ' " h m s o o o o ' " o ' " o ' " o ' "
Longitude Longitude Longitude Longitude
119 50 52 -15 0 0 13 34 45 62 185 -54 120 9 31 119 32 14 120 38 15 119 3 34 -0.10
119 58 10 -16 0 0 13 34 29 63 185 -54 120 16 54 119 39 26 120 45 46 119 10 38 -0.10
120 5 36 -17 0 0 13 34 12 64 185 -55 120 24 26 119 46 47 120 53 28 119 17 49 -0.10
120 13 11 -18 0 0 13 33 56 65 186 -55 120 32 8 119 54 16 121 1 19 119 25 9 -0.10
120 20 56 -19 0 0 13 33 39 66 186 -55 120 39 59 120 1 54 121 9 20 119 32 36 -0.10
120 28 50 -20 0 0 13 33 23 67 186 -55 120 48 0 120 9 40 121 17 32 119 40 12 -0.10
120 36 53 -21 0 0 13 33 6 68 187 -56 120 56 11 120 17 36 121 25 55 119 47 56 -0.10
120 45 6 -22 0 0 13 32 49 69 187 -56 121 4 32 120 25 41 121 34 29 119 55 49 -0.10
120 53 29 -23 0 0 13 32 32 70 188 -56 121 13 3 120 33 56 121 43 13 120 3 51 -0.09
121 2 2 -24 0 0 13 32 15 71 188 -56 121 21 46 120 42 20 121 52 10 120 12 1 -0.09
121 10 46 -25 0 0 13 31 58 72 189 -56 121 30 39 120 50 55 122 1 18 120 20 21 -0.09
121 19 41 -26 0 0 13 31 40 73 189 -57 121 39 44 120 59 39 122 10 38 120 28 50 -0.09
121 28 47 -27 0 0 13 31 23 74 190 -57 121 49 1 121 8 35 122 20 11 120 37 30 -0.09
121 38 5 -28 0 0 13 31 6 75 191 -57 121 58 29 121 17 41 122 29 57 120 46 19 -0.09
121 47 34 -29 0 0 13 30 48 76 192 -57 122 8 11 121 26 59 122 39 57 120 55 19 -0.09
121 57 16 -30 0 0 13 30 30 77 193 -57 122 18 5 121 36 29 122 50 10 121 4 29 -0.09
122 7 11 -31 0 0 13 30 13 77 194 -57 122 28 13 121 46 11 123 0 38 121 13 51 -0.09
122 17 19 -32 0 0 13 29 55 78 196 -57 122 38 35 121 56 5 123 11 21 121 23 25 -0.08
122 27 41 -33 0 0 13 29 37 79 198 -57 122 49 11 122 6 13 123 22 20 121 33 10 -0.08
122 38 18 -34 0 0 13 29 19 80 200 -57 123 0 2 122 16 34 123 33 34 121 43 9 -0.08
122 49 9 -35 0 0 13 29 1 81 203 -57 123 11 10 122 27 10 123 45 6 121 53 20 -0.08
123 0 16 -36 0 0 13 28 43 82 206 -57 123 22 34 122 38 0 123 56 56 122 3 45 -0.08
123 11 40 -37 0 0 13 28 25 83 210 -56 123 34 15 122 49 7 124 9 5 122 14 24 -0.08
123 23 22 -38 0 0 13 28 7 83 216 -56 123 46 15 123 0 29 124 21 33 122 25 19 -0.08
- 66 0 0 .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. -50 48 57 ....
Uncertainty in time = +/- 8 secs
Prediction of 2016 May 5.0
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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