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Updated: 2008 NOV 13, 22:50 UT
Event Rank : 99
(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 2008 Nov 21 UT, the 99 km diameter asteroid (1021) Flammario will occult a 10.5 mag star in the constellation Cetus for observers along a path across northern and western Queensland, and southeastern Northern Territory in evening twilight, and across Papua - New Guinea from Mafang to Kikori.
In the case of an occultation, the combined light of the asteroid and the star will drop by 2.0 mag to 12.4 mag (the magnitude of the asteroid) for at most 10.3 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Alice Monet, 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
148 18 5 - 2 0 0 9 55 8 68 163 -28 148 48 12 147 47 54 149 7 25 147 28 32
147 51 53 - 3 0 0 9 54 55 68 161 -27 148 22 5 147 21 35 148 41 23 147 2 9
147 25 14 - 4 0 0 9 54 43 69 159 -26 147 55 34 146 54 49 148 14 55 146 35 18
146 58 7 - 5 0 0 9 54 30 70 157 -25 147 28 35 146 27 34 147 48 1 146 7 58
146 30 31 - 6 0 0 9 54 18 71 154 -24 147 1 7 145 59 49 147 20 39 145 40 7
146 2 23 - 7 0 0 9 54 5 71 152 -23 146 33 9 145 31 31 146 52 47 145 11 43
145 33 42 - 8 0 0 9 53 52 72 149 -23 146 4 38 145 2 40 146 24 23 144 42 44
145 4 26 - 9 0 0 9 53 40 72 146 -22 145 35 34 144 33 12 145 55 26 144 13 8
144 34 33 -10 0 0 9 53 27 73 143 -21 145 5 53 144 3 5 145 25 52 143 42 54
144 4 0 -11 0 0 9 53 13 73 139 -20 144 35 33 143 32 19 144 55 42 143 11 58
Latitude Latitude Latitude Latitude
143 0 0 -13 1 26 9 52 47 74 132 -18 -14 0 40 -12 1 32 -14 38 15 -11 22 51
142 0 0 -14 50 9 9 52 23 74 125 -16 -15 47 44 -13 51 57 -16 24 17 -13 14 22
141 0 0 -16 34 3 9 51 59 74 118 -14 -17 30 3 -15 37 28 -18 5 37 -15 0 57
140 0 0 -18 13 17 9 51 37 74 111 -13 -19 7 47 -17 18 15 -19 42 25 -16 42 44
139 0 0 -19 48 3 9 51 15 73 106 -11 -20 41 7 -18 54 29 -21 14 51 -18 19 55
138 0 0 -21 18 30 9 50 54 73 100 -9 -22 10 13 -20 26 20 -22 43 5 -19 52 41
137 0 0 -22 44 51 9 50 34 72 96 -8 -23 35 16 -21 54 0 -24 7 20 -21 21 13
136 0 0 -24 7 16 9 50 15 71 92 -6 -24 56 28 -23 17 40 -25 27 45 -22 45 42
135 0 0 -25 25 55 9 49 57 70 89 -5 -26 13 57 -24 37 31 -26 44 30 -24 6 20
134 0 0 -26 41 0 9 49 39 69 86 -4 -27 27 56 -25 53 44 -27 57 48 -25 23 17
133 0 0 -27 52 41 9 49 22 68 84 -2 -28 38 34 -27 6 29 -29 7 46 -26 36 43
132 0 0 -29 1 7 9 49 6 67 82 -1 -29 46 1 -28 15 56 -30 14 35 -27 46 50
Uncertainty in time = +/- 4 secs
[Prediction of 2008 Nov 13.0]
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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