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Updated: 2016 JUL 10, 15:48 UT
Event Rank : 40
(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 Aug 19 UT, the 99 km diameter asteroid (506) Marion will occult a 12.5 mag star in the constellation Scorpius for observers along a path across north Island New Zealand.
In the case of an occultation, the combined light of the asteroid and the star will drop by 2.33 mag to 14.70 mag (the magnitude of the asteroid) for at most 12.6 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
173 36 7 -29 0 0 9 41 53 71 247 -48 174 9 38 173 2 45 176 29 58 170 45 58 -0.33
173 56 26 -30 0 0 9 41 39 72 250 -48 174 30 20 173 22 40 176 52 23 171 4 18 -0.33
174 17 32 -31 0 0 9 41 24 72 253 -48 174 51 52 173 43 21 177 15 44 171 23 19 -0.33
174 39 28 -32 0 0 9 41 10 72 256 -48 175 14 15 174 4 51 177 40 3 171 43 3 -0.33
175 2 18 -33 0 0 9 40 55 72 259 -48 175 37 33 174 27 12 178 5 23 172 3 32 -0.33
175 26 3 -34 0 0 9 40 41 71 262 -48 176 1 48 174 50 27 178 31 47 172 24 49 -0.33
175 50 46 -35 0 0 9 40 26 71 265 -48 176 27 4 175 14 40 178 59 19 172 46 56 -0.33
176 16 32 -36 0 0 9 40 11 71 268 -47 176 53 23 175 39 52 179 28 4 173 9 55 -0.33
176 43 23 -37 0 0 9 39 57 71 270 -47 177 20 50 176 6 8 179 58 5 173 33 51 -0.33
177 11 23 -38 0 0 9 39 42 70 273 -47 177 49 28 176 33 31 -179 30 32 173 58 46 -0.33
177 40 38 -39 0 0 9 39 27 70 275 -47 178 19 23 177 2 6 -178 57 43 174 24 43 -0.33
178 11 11 -40 0 0 9 39 13 69 278 -47 178 50 38 177 31 57 -178 23 22 174 51 47 -0.33
Latitude Latitude Latitude Latitude
179 0 0 -41 30 38 9 38 50 69 281 -47 -40 17 28 -42 42 46 -35 1 26 -47 32 6 -0.33
180 0 0 -43 13 59 9 38 25 68 284 -46 -42 4 8 -44 22 57 -37 3 44 -49 0 18 -0.32
-179 0 0 -44 49 26 9 38 1 67 287 -46 -43 42 33 -45 55 33 -38 55 56 -50 22 3 -0.32
-178 0 0 -46 17 51 9 37 40 66 289 -46 -45 13 38 -47 21 23 -40 39 17 -51 38 0 -0.32
-177 0 0 -47 39 58 9 37 19 65 291 -45 -46 38 10 -48 41 9 -42 14 49 -52 48 43 -0.32
-176 0 0 -48 56 23 9 37 0 63 292 -45 -47 56 48 -49 55 26 -43 43 25 -53 54 41 -0.32
Uncertainty in time = +/- 26 secs
Prediction of 2016 Jul 10.0
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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