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Updated: 2007 MAR 30, 22:57 UT
Event Rank : 34
(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 Apr 26 UT, the 26 km diameter asteroid (1791) Patsayev will occult a 10.1 mag star in the constellation Virgo for observers along a significant uncertainty path beginning low in the east over South Australia and then approximately following the NSW/Victorian border.
In the case of an occultation, the combined light of the asteroid and the star will drop by 5.0 mag to 15.1 mag (the magnitude of the asteroid) for at most 2.5 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
153 10 59 -40 15 2 8 42 28 24 80 -19 152 50 13 -40 20 4 153 31 29 -40 9 59 151 25 1 -40 39 38 154 50 0 -39 49 41
152 15 15 -39 40 9 8 42 36 23 81 -19 151 54 10 -39 45 4 152 36 2 -39 35 12 150 27 35 -40 4 12 153 55 37 -39 15 18
151 17 50 -39 5 10 8 42 44 23 82 -18 150 56 24 -39 9 58 151 38 58 -39 0 19 149 28 13 -39 28 37 152 59 47 -38 40 51
150 18 35 -38 30 2 8 42 52 22 83 -17 149 56 43 -38 34 43 150 40 6 -38 25 18 148 26 40 -38 52 51 152 2 21 -38 6 16
149 17 15 -37 54 43 8 43 0 21 84 -16 148 54 54 -37 59 16 149 39 14 -37 50 7 147 22 39 -38 16 51 151 3 8 -37 31 32
148 13 34 -37 19 10 8 43 7 21 84 -16 147 50 39 -37 23 35 148 36 7 -37 14 43 146 15 48 -37 40 34 150 1 56 -36 56 38
147 7 13 -36 43 21 8 43 15 20 85 -15 146 43 37 -36 47 37 147 30 24 -36 39 3 145 5 42 -37 3 55 148 58 29 -36 21 31
145 57 48 -36 7 12 8 43 23 19 86 -14 145 33 24 -36 11 17 146 21 45 -36 3 3 143 51 45 -36 26 49 147 52 29 -35 46 7
144 44 48 -35 30 37 8 43 31 18 87 -13 144 19 25 -35 34 31 145 9 40 -35 26 40 142 33 12 -35 49 10 146 43 34 -35 10 24
143 27 31 -34 53 32 8 43 39 17 88 -12 143 0 56 -34 57 11 143 53 31 -34 49 47 141 9 2 -35 10 48 145 31 14 -34 34 16
142 5 5 -34 15 46 8 43 47 16 89 -10 141 37 0 -34 19 10 142 32 29 -34 12 17 139 37 46 -34 31 30 144 14 54 -33 57 39
140 36 13 -33 37 10 8 43 54 15 90 -9 140 6 10 -33 40 14 141 5 24 -33 33 59 137 57 10 -33 50 57 142 53 44 -33 20 25
138 59 2 -32 57 27 8 44 2 13 91 -8 138 26 22 -33 0 4 139 30 37 -32 54 40 136 3 31 -33 8 35 141 26 36 -32 42 23
137 10 35 -32 16 10 8 44 10 12 92 -6 136 34 6 -32 18 11 137 45 32 -32 13 55 133 49 41 -32 23 23 139 51 54 -32 3 20
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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