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Updated: 2008 FEB 27, 20:09 UT
Event Rank : 96
(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 Mar 10 UT, the 145 km diameter asteroid (117) Lomia will occult a 10.2 mag star in the constellation Cancer for observers along a broad path across Australia from Mackay in Queensland to Port Pirie (just west of Adelaide) in South Australia.
In the case of an occultation, the combined light of the asteroid and the star will drop by 2.7 mag to 12.8 mag (the magnitude of the asteroid) for at most 17.0 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
133 31 23 -39 0 0 10 53 43 18 23 -16 132 20 27 134 42 31 131 20 59 135 42 26
134 24 2 -38 0 0 10 53 37 20 23 -17 133 13 55 135 34 22 132 15 9 136 33 37
135 16 23 -37 0 0 10 53 31 21 22 -18 134 7 1 136 25 58 133 8 53 137 24 36
136 8 27 -36 0 0 10 53 24 22 21 -19 134 59 47 137 17 21 134 2 16 138 15 26
137 0 20 -35 0 0 10 53 17 23 21 -20 135 52 19 138 8 35 134 55 22 139 6 8
137 52 3 -34 0 0 10 53 10 24 20 -21 136 44 39 138 59 44 135 48 12 139 56 48
138 43 41 -33 0 0 10 53 3 25 20 -22 137 36 49 139 50 49 136 40 52 140 47 27
139 35 16 -32 0 0 10 52 55 27 19 -23 138 28 55 140 41 54 137 33 23 141 38 8
140 26 50 -31 0 0 10 52 46 28 18 -24 139 20 57 141 33 2 138 25 49 142 28 54
141 18 28 -30 0 0 10 52 38 29 18 -25 140 13 0 142 24 16 139 18 13 143 19 48
142 10 11 -29 0 0 10 52 29 30 17 -26 141 5 5 143 15 37 140 10 38 144 10 52
143 2 2 -28 0 0 10 52 19 31 16 -27 141 57 16 144 7 9 141 3 7 145 2 8
143 54 5 -27 0 0 10 52 10 32 16 -28 142 49 36 144 58 55 141 55 42 145 53 41
144 46 20 -26 0 0 10 51 59 34 15 -29 143 42 7 145 50 56 142 48 27 146 45 31
145 38 52 -25 0 0 10 51 49 35 15 -30 144 34 52 146 43 17 143 41 23 147 37 42
146 31 43 -24 0 0 10 51 38 36 14 -31 145 27 53 147 35 58 144 34 33 148 30 16
147 24 56 -23 0 0 10 51 27 37 13 -32 146 21 13 148 29 3 145 28 1 149 23 17
148 18 32 -22 0 0 10 51 15 38 12 -34 147 14 55 149 22 36 146 21 49 150 16 46
149 12 36 -21 0 0 10 51 4 39 12 -35 148 9 2 150 16 37 147 15 59 151 10 46
150 7 9 -20 0 0 10 50 51 40 11 -36 149 3 37 151 11 11 148 10 35 152 5 21
151 2 16 -19 0 0 10 50 39 42 10 -37 149 58 41 152 6 20 149 5 39 153 0 34
151 57 58 -18 0 0 10 50 26 43 9 -38 150 54 19 153 2 7 150 1 14 153 56 27
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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