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Updated: 2011 SEP 12, 07:55 UT
Event Rank : 44
(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 2011 Sep 24 UT, the 98 km diameter asteroid (2674) Pandarus will occult a 11.8 mag star in the constellation Aquarius for observers along a path across Tasmania, directly over Hobart. The path includes the south-eastern half of the state, and the one sigma limit covers the whole state.
In the case of an occultation, the combined light of the asteroid and the star will drop by 4.5 mag to 16.3 mag (the magnitude of the asteroid) for at most 7.2 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, TMO astrometry for the asteroid kindly provided by Bill Owen, 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 Limit1 Path Limit2 Error Limit1 Error Limit2
E. Longitude Latitude U.T. Alt Az Alt
o ' " o ' " h m s o o o o ' " o ' " o ' " o ' " o ' " o ' " o ' " o ' "
Longitude Latitude Longitude Latitude Longitude Latitude Longitude Latitude
158 58 23 -38 32 24 17 10 5 11 267 -24 161 58 8 -38 35 0 156 31 31 -38 24 33 ... .. .. .. .. .. 150 54 47 -37 46 43
156 42 28 -39 16 42 17 10 11 12 268 -25 159 14 22 -39 24 8 154 31 45 -39 5 57 ... .. .. .. .. .. 149 19 19 -38 23 27
154 43 21 -39 58 17 17 10 17 14 270 -26 156 58 36 -40 8 42 152 43 38 -39 45 29 167 32 56 -40 1 28 147 49 33 -38 59 16
152 55 47 -40 38 1 17 10 23 15 271 -27 154 59 43 -40 50 34 151 4 5 -40 23 38 163 22 46 -41 5 39 146 24 26 -39 34 21
151 16 43 -41 16 24 17 10 29 17 272 -28 153 12 24 -41 30 35 149 31 11 -41 0 45 160 32 12 -41 56 53 145 3 12 -40 8 50
149 44 15 -41 53 46 17 10 35 18 274 -29 151 33 36 -42 9 15 148 3 36 -41 37 2 158 13 29 -42 42 59 143 45 14 -40 42 49
148 17 4 -42 30 18 17 10 41 19 275 -29 150 1 24 -42 46 54 146 40 22 -42 12 40 156 13 10 -43 26 9 142 30 5 -41 16 22
146 54 12 -43 6 12 17 10 48 20 276 -30 148 34 29 -43 23 44 145 20 48 -42 47 44 154 25 12 -44 7 21 141 17 22 -41 49 34
145 34 59 -43 41 33 17 10 54 20 277 -30 147 11 55 -43 59 56 144 4 20 -43 22 22 152 46 13 -44 47 10 140 6 47 -42 22 28
144 18 50 -44 16 28 17 11 0 21 278 -31 145 52 58 -44 35 37 142 50 31 -43 56 37 151 14 8 -45 25 57 138 58 3 -42 55 7
Uncertainty in time = +/- 14 secs
Prediction of 2011 Sep 12.0
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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