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Updated: 2009 JUN 12, 18:33 UT
Event Rank : 93
(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 2009 Jul 24 UT, the 189 km diameter asteroid (372) Palma will occult a 12.7 mag star in the constellation Ara for observers along a wide, somewhat uncertain path across southern New Zealand.
In the case of an occultation, the combined light of the asteroid and the star will drop by 1.2 mag to 13.5 mag (the magnitude of the asteroid) for at most 14.1 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 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
154 36 57 -18 0 0 9 23 56 57 163 -28 155 34 48 153 39 17 156 30 31 152 44 4
155 2 13 -19 0 0 9 23 49 59 163 -28 156 0 29 154 4 9 156 56 35 153 8 33
155 27 52 -20 0 0 9 23 41 60 163 -29 156 26 34 154 29 22 157 23 6 153 33 23
155 53 55 -21 0 0 9 23 33 61 163 -30 156 53 5 154 54 58 157 50 4 153 58 33
156 20 24 -22 0 0 9 23 26 62 163 -30 157 20 3 155 20 58 158 17 32 154 24 6
156 47 20 -23 0 0 9 23 18 63 163 -31 157 47 31 155 47 24 158 45 30 154 50 2
157 14 45 -24 0 0 9 23 10 64 163 -31 158 15 29 156 14 16 159 14 1 155 16 24
157 42 41 -25 0 0 9 23 2 65 163 -32 158 43 59 156 41 37 159 43 6 155 43 13
158 11 8 -26 0 0 9 22 53 66 163 -32 159 13 4 157 9 28 160 12 47 156 10 30
158 40 11 -27 0 0 9 22 45 67 163 -33 159 42 46 157 37 52 160 43 7 156 38 17
159 9 49 -28 0 0 9 22 37 68 163 -33 160 13 6 158 6 50 161 14 8 157 6 37
159 40 6 -29 0 0 9 22 28 69 164 -34 160 44 7 158 36 23 161 45 52 157 35 30
160 0 0 -29 38 44 9 22 23 70 164 -34 -27 34 16 -31 42 54 -25 34 19 -33 42 1
161 0 0 -31 32 5 9 22 7 72 164 -35 -29 30 13 -33 33 42 -27 32 49 -35 30 24
162 0 0 -33 20 27 9 21 51 74 164 -36 -31 21 9 -35 19 32 -29 26 15 -37 13 50
163 0 0 -35 3 56 9 21 36 76 165 -37 -33 7 9 -37 0 32 -31 14 44 -38 52 27
164 0 0 -36 42 41 9 21 21 77 165 -38 -34 48 23 -38 36 50 -32 58 23 -40 26 24
165 0 0 -38 16 51 9 21 7 79 167 -38 -36 25 0 -40 8 36 -34 37 22 -41 55 52
166 0 0 -39 46 37 9 20 53 80 168 -39 -37 57 8 -41 36 0 -36 11 49 -43 21 2
167 0 0 -41 12 9 9 20 40 82 171 -39 -39 24 59 -42 59 14 -37 41 55 -44 42 3
168 0 0 -42 33 37 9 20 27 83 174 -40 -40 48 43 -44 18 27 -39 7 50 -45 59 8
169 0 0 -43 51 13 9 20 15 84 180 -40 -42 8 30 -45 33 52 -40 29 44 -47 12 26
170 0 0 -45 5 6 9 20 4 85 191 -41 -43 24 31 -46 45 38 -41 47 49 -48 22 10
171 0 0 -46 15 28 9 19 52 86 208 -41 -44 36 57 -47 53 56 -43 2 15 -49 28 29
172 0 0 -47 22 28 9 19 42 86 235 -41 -45 45 57 -48 58 56 -44 13 11 -50 31 35
Uncertainty in time = +/- 7 secs
Prediction of 2009 Jun 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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