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Updated: 2007 OCT 13, 23:03 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 2007 Nov 12 UT, the 75 km diameter asteroid (25) Phocaea will occult a 11.6 mag star in the constellation Monoceros for observers along a path across New Zealand centred near Gisbourne, Wellington and Christchurch.
In the case of an occultation, the combined light of the asteroid and the star will drop by 1.8 mag to 13.1 mag (the magnitude of the asteroid) for at most 6.3 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, 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
-176 15 17 -32 54 32 12 44 53 34 69 -36 -175 37 1 -32 54 14 -176 54 4 -32 54 49 -173 45 47 -32 53 5 -178 52 57 -32 55 25
-177 7 20 -34 5 54 12 45 3 33 69 -36 -176 27 52 -34 5 38 -177 47 22 -34 6 8 -174 33 18 -34 4 36 -179 50 17 -34 6 34
-178 4 26 -35 18 0 12 45 13 32 69 -35 -177 23 36 -35 17 47 -178 45 53 -35 18 11 -175 25 18 -35 16 53 179 6 37 -35 18 26
-179 7 17 -36 30 54 12 45 22 30 69 -34 -178 24 55 -36 30 44 -179 50 21 -36 31 0 -176 22 21 -36 30 0 177 56 51 -36 31 2
179 43 14 -37 44 37 12 45 32 29 70 -33 -179 32 37 -37 44 31 178 58 18 -37 44 39 -177 25 11 -37 43 59 176 39 20 -37 44 25
178 26 2 -38 59 11 12 45 42 28 70 -32 179 12 16 -38 59 11 177 38 55 -38 59 8 -178 34 40 -38 58 52 175 12 39 -38 58 34
176 59 44 -40 14 39 12 45 51 26 70 -31 177 48 26 -40 14 46 176 10 1 -40 14 29 -179 51 53 -40 14 43 173 35 0 -40 13 31
175 22 33 -41 31 2 12 46 1 25 71 -30 176 14 12 -41 31 16 174 29 42 -41 30 43 178 41 44 -41 31 34 171 43 53 -41 29 14
173 32 4 -42 48 19 12 46 11 23 72 -29 174 27 21 -42 48 44 172 35 18 -42 47 49 177 4 25 -42 49 27 169 35 50 -42 45 40
171 24 53 -44 6 28 12 46 20 21 73 -28 172 24 47 -44 7 6 170 23 7 -44 5 42 175 13 43 -44 8 23 167 5 36 -44 2 38
168 56 6 -45 25 21 12 46 30 19 74 -27 170 2 5 -45 26 18 167 47 35 -45 24 16 173 6 18 -45 28 20 164 4 43 -45 19 51
165 57 51 -46 44 45 12 46 40 17 76 -26 167 12 25 -46 46 9 164 39 38 -46 43 9 170 37 18 -46 49 13 160 17 23 -46 36 37
162 16 17 -48 4 5 12 46 50 14 79 -24 163 44 8 -48 6 11 160 42 18 -48 1 38 167 39 8 -48 10 51 155 5 35 -47 51 0
157 20 58 -49 21 53 12 46 59 11 82 -23 159 13 45 -49 25 21 155 14 16 -49 17 37 163 58 46 -49 32 43 144 43 36 -48 50 36
149 18 31 -50 32 4 12 47 9 6 88 -21 152 32 39 -50 40 4 143 40 57 -50 16 2 159 9 9 -50 53 36 ... .. .. .. .. ..
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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