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Updated: 2013 JUN 12, 15:28 UT
Event Rank : 8
(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 2013 Aug 01 UT, the 12 km diameter asteroid (15416) 1998 DZ2 will occult a 9.8 mag star in the constellation Piscis Austrinus for observers along a narrow and quite uncertain north-to-south path passing near New Zealand. The path is predicted to miss west of Auckland, and later in the South Island passes near Queenstown and Invercargill.
In the case of an occultation, the combined light of the asteroid and the star will drop by 5.6 mag to 15.4 mag (the magnitude of the asteroid) for at most 1.3 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, 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
174 6 58 -28 0 0 15 29 59 79 248 -48 174 3 6 174 10 49 173 3 7 175 10 49
173 47 17 -29 0 0 15 30 11 79 253 -48 173 43 24 173 51 11 172 42 51 174 51 44
173 27 29 -30 0 0 15 30 24 80 258 -48 173 23 33 173 31 25 172 22 25 174 32 33
173 7 32 -31 0 0 15 30 37 80 264 -48 173 3 34 173 11 30 172 1 48 174 13 16
172 47 26 -32 0 0 15 30 50 81 270 -48 172 43 25 172 51 27 171 40 59 173 53 51
172 27 9 -33 0 0 15 31 3 81 277 -48 172 23 6 172 31 13 171 19 58 173 34 19
172 6 41 -34 0 0 15 31 15 81 283 -48 172 2 35 172 10 47 170 58 43 173 14 37
171 46 0 -35 0 0 15 31 28 81 290 -48 171 41 51 171 50 10 170 37 14 172 54 45
171 25 7 -36 0 0 15 31 41 80 297 -48 171 20 54 171 29 19 170 15 28 172 34 42
171 3 58 -37 0 0 15 31 54 80 303 -48 170 59 42 171 8 13 169 53 25 172 14 28
170 42 34 -38 0 0 15 32 7 80 309 -48 170 38 15 170 46 53 169 31 3 171 54 0
170 20 52 -39 0 0 15 32 19 79 314 -48 170 16 30 170 25 15 169 8 22 171 33 19
169 58 52 -40 0 0 15 32 32 79 319 -48 169 54 26 170 3 19 168 45 18 171 12 22
169 36 32 -41 0 0 15 32 45 78 323 -48 169 32 2 169 41 3 168 21 51 170 51 8
169 13 51 -42 0 0 15 32 58 77 327 -48 169 9 16 169 18 25 167 57 59 170 29 36
168 50 46 -43 0 0 15 33 10 77 330 -48 168 46 7 168 55 25 167 33 40 170 7 45
168 27 15 -44 0 0 15 33 23 76 334 -47 168 22 32 168 31 59 167 8 51 169 45 32
168 3 18 -45 0 0 15 33 36 75 336 -47 167 58 29 168 8 7 166 43 30 169 22 56
167 38 50 -46 0 0 15 33 48 74 339 -47 167 33 56 167 43 44 166 17 35 168 59 56
167 13 51 -47 0 0 15 34 1 73 341 -47 167 8 51 167 18 51 165 51 4 168 36 28
166 48 17 -48 0 0 15 34 13 73 343 -46 166 43 11 166 53 22 165 23 52 168 12 30
166 22 5 -49 0 0 15 34 26 72 345 -46 166 16 53 166 27 17 164 55 56 167 48 1
165 55 12 -50 0 0 15 34 38 71 347 -46 165 49 54 166 0 30 164 27 13 167 22 56
165 27 35 -51 0 0 15 34 50 70 349 -45 165 22 9 165 33 0 163 57 39 166 57 14
164 59 9 -52 0 0 15 35 3 69 350 -45 164 53 36 165 4 42 163 27 10 166 30 50
Uncertainty in time = +/- 12 secs
Prediction of 2013 Apr 8.0
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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