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Updated: 2007 MAY 04, 04:00 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 2007 Jun 04 UT, the 40 km diameter asteroid (456) Abnoba will occult a 11.4 mag star in the constellation Ophiuchus for observers along a path across south-eastern Australia at very low altitude, including Melbourne at about 9 degrees elevation.
In the case of an occultation, the combined light of the asteroid and the star will drop by 1.1 mag to 12.0 mag (the magnitude of the asteroid) for at most 4.0 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
152 22 5 -42 26 48 8 39 22 15 92 -24 151 26 40 -42 27 34 153 15 8 -42 25 32 149 51 3 -42 27 35 154 36 45 -42 22 36
151 44 55 -41 55 43 8 39 28 15 93 -23 150 48 20 -41 56 9 152 38 59 -41 54 46 149 10 15 -41 55 29 154 1 56 -41 52 17
151 5 49 -41 24 22 8 39 34 14 93 -23 150 7 49 -41 24 23 152 1 5 -41 23 46 148 26 46 -41 22 56 153 25 36 -41 21 45
150 24 33 -40 52 40 8 39 40 14 94 -22 149 24 51 -40 52 14 151 21 13 -40 52 28 147 40 13 -40 49 52 152 47 35 -40 50 59
149 40 50 -40 20 34 8 39 46 13 94 -22 148 39 5 -40 19 37 150 39 10 -40 20 49 146 50 3 -40 16 10 152 7 43 -40 19 57
148 54 18 -39 48 0 8 39 51 13 95 -21 147 50 4 -39 46 25 149 54 40 -39 48 46 145 55 32 -39 41 39 151 25 47 -39 48 35
148 4 29 -39 14 50 8 39 57 12 96 -20 146 57 11 -39 12 31 149 7 19 -39 16 13 144 55 34 -39 6 6 150 41 33 -39 16 51
147 10 47 -38 40 58 8 40 3 11 96 -19 145 59 34 -38 37 44 148 16 41 -38 43 5 143 48 31 -38 29 10 149 54 40 -38 44 39
146 12 19 -38 6 11 8 40 9 10 97 -19 144 55 59 -38 1 47 147 22 5 -38 9 12 142 31 39 -37 50 15 149 4 43 -38 11 54
145 7 48 -37 30 14 8 40 14 9 98 -18 143 44 25 -37 24 14 146 22 39 -37 34 24 140 59 37 -37 8 15 148 11 8 -37 38 28
143 55 12 -36 52 39 8 40 20 8 98 -17 142 21 25 -36 44 23 145 17 4 -36 58 24 138 59 1 -36 20 18 147 13 10 -37 4 13
142 30 59 -36 12 43 8 40 26 7 99 -15 140 39 47 -36 0 41 144 3 12 -36 20 44 134 59 0 -35 7 18 146 9 43 -36 28 53
140 47 41 -35 28 50 8 40 32 6 100 -14 138 17 49 -35 8 33 142 37 24 -35 40 38 ... .. .. .. .. .. 144 59 5 -35 52 7
138 22 34 -34 36 13 8 40 37 4 102 -12 ... .. .. .. .. .. 140 51 45 -34 56 26 ... .. .. .. .. .. 143 38 28 -35 13 20
... .. .. .. .. .. .. .. .. .. .. .. ... .. .. .. .. .. 138 21 23 -34 2 52 ... .. .. .. .. .. 142 2 31 -34 31 23
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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