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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 the time for your location)
On 2004 Jul 17 UT, the 59 km diameter asteroid (1712) Angola will occult a 10.1 mag star in the constellation Pegasus for observers along a path across PNG and northern Australia.
In the case of an occultation, the combined light of the asteroid and the star will drop by 5.4 mag to 15.5 mag (the magnitude of the asteroid) for at most 7.3 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Ron Stone, 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 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
... .. .. -23 0 0 .. .. .. .. .. .. ... .. .. ... .. .. 126 33 9 ... .. ..
... .. .. -22 0 0 .. .. .. .. .. .. 126 11 2 ... .. .. 128 40 3 ... .. ..
127 15 2 -21 0 0 14 17 24 2 65 -71 128 16 23 126 9 43 130 28 59 ... .. ..
129 8 49 -20 0 0 14 17 26 4 65 -73 130 3 52 128 10 59 132 4 45 125 40 15
130 47 48 -19 0 0 14 17 30 6 64 -74 131 38 15 129 55 13 133 30 16 127 40 50
132 15 31 -18 0 0 14 17 35 8 64 -76 133 2 27 131 26 53 134 47 28 129 24 11
133 34 16 -17 0 0 14 17 40 9 63 -76 134 18 24 132 48 44 135 57 45 130 54 52
134 45 37 -16 0 0 14 17 46 11 63 -77 135 27 28 134 2 36 137 2 7 132 15 43
135 50 43 -15 0 0 14 17 53 12 63 -78 136 30 40 135 9 46 138 1 20 133 28 32
136 50 26 -14 0 0 14 18 0 13 63 -78 137 28 46 136 11 12 138 56 2 134 34 41
137 45 24 -13 0 0 14 18 8 15 63 -78 138 22 21 137 7 40 139 46 41 135 35 6
138 36 10 -12 0 0 14 18 16 16 63 -78 139 11 55 137 59 42 140 33 42 136 30 32
139 23 10 -11 0 0 14 18 24 17 63 -77 139 57 52 138 47 49 141 17 23 137 21 33
140 6 44 -10 0 0 14 18 33 18 63 -77 140 40 30 139 32 21 141 58 3 138 8 38
140 47 10 - 9 0 0 14 18 42 19 63 -77 141 20 8 140 13 39 142 35 54 138 52 10
141 24 43 - 8 0 0 14 18 52 20 63 -76 141 56 57 140 51 57 143 11 10 139 32 26
141 59 35 - 7 0 0 14 19 1 21 63 -75 142 31 11 141 27 30 143 44 0 140 9 43
142 31 58 - 6 0 0 14 19 11 22 63 -74 143 3 0 142 0 29 144 14 33 140 44 14
143 2 0 - 5 0 0 14 19 21 23 63 -73 143 32 32 142 31 3 144 42 58 141 16 11
143 29 50 - 4 0 0 14 19 32 24 64 -73 143 59 54 142 59 22 145 9 20 141 45 42
143 55 35 - 3 0 0 14 19 42 25 64 -72 144 25 15 143 25 32 145 33 47 142 12 58
144 19 21 - 2 0 0 14 19 53 26 64 -71 144 48 39 143 49 40 145 56 23 142 38 3
144 41 13 - 1 0 0 14 20 4 27 64 -70 145 10 11 144 11 52 146 17 14 143 1 6
145 1 16 0 0 0 14 20 16 27 65 -69 145 29 57 144 32 13 146 36 22 143 22 11
145 19 33 1 0 0 14 20 27 28 65 -68 145 48 0 144 50 46 146 53 52 143 41 24
145 36 10 2 0 0 14 20 39 29 66 -67 146 4 24 145 7 36 147 9 47 143 58 48
145 51 8 3 0 0 14 20 50 30 66 -66 146 19 11 145 22 45 147 24 10 144 14 27
146 4 30 4 0 0 14 21 2 30 67 -65 146 32 24 145 36 17 147 37 2 144 28 23
146 16 19 5 0 0 14 21 14 31 67 -64 146 44 5 145 48 14 147 48 27 144 40 41
146 26 36 6 0 0 14 21 27 31 68 -63 146 54 16 145 58 38 147 58 25 144 51 21
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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