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Updated: 2013 JAN 26, 17:03 UT
Event Rank : 72
(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 Feb 19 UT, the 147 km diameter asteroid (388) Charybdis will occult a 12.0 mag star in the constellation Auriga for observers along a path over central Queensland near Longreach (low altitude).
In the case of an occultation, the combined light of the asteroid and the star will drop by 2.3 mag to 14.1 mag (the magnitude of the asteroid) for at most 39.5 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
135 56 49 - 8 18 38 13 47 37 33 316 -62 136 49 6 - 8 23 53 135 5 23 - 8 14 8 138 15 49 - 8 34 4 133 43 44 - 8 8 18
136 44 2 -10 16 47 13 48 16 31 316 -61 137 37 52 -10 23 7 135 51 11 -10 11 17 139 7 22 -10 35 16 134 27 30 -10 4 0
137 38 14 -12 21 4 13 48 55 29 316 -60 138 34 3 -12 28 46 136 43 35 -12 14 18 140 7 14 -12 43 27 135 17 16 -12 5 12
138 41 22 -14 32 59 13 49 33 27 316 -59 139 39 50 -14 42 30 137 44 19 -14 24 36 141 17 58 -15 0 34 136 14 35 -14 13 10
139 56 23 -16 54 50 13 50 12 24 316 -58 140 58 33 -17 6 51 138 56 3 -16 44 13 142 43 44 -17 29 40 137 21 42 -16 29 40
141 28 14 -19 30 16 13 50 51 21 316 -56 142 35 55 -19 46 0 140 23 5 -19 16 26 144 32 5 -20 16 10 138 42 8 -18 57 27
143 26 12 -22 26 2 13 51 29 17 315 -55 144 43 14 -22 48 1 142 13 14 -22 6 56 146 59 22 -23 31 30 140 21 58 -21 41 3
146 12 19 -25 57 38 13 52 8 13 314 -52 147 50 0 -26 33 24 144 43 39 -25 28 2 150 59 58 -27 52 39 142 33 27 -24 49 26
151 23 51 -31 11 30 13 52 47 6 312 -48 156 29 42 -34 5 10 148 53 14 -30 0 30 ... .. .. .. .. .. 145 49 49 -28 46 10
Uncertainty in time = +/- 59 secs
Prediction of 2013 Jan 27.0
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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