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Updated: 2012 Dec 16, 20:53 UT
Event Rank : 71
(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 2013 Jan 25 UT, the 37 km diameter asteroid (1116) Catriona will occult a 11.7 mag star in the constellation Auriga for observers along a path across eastern Queensland and central New South Wales.
In the case of an occultation, the combined light of the asteroid and the star will drop by 1.8 mag to 13.3 mag (the magnitude of the asteroid) for at most 4.5 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.
Occultation of TYC 3379-00397-1 by 1116 Catriona on 2013 Jan 25
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
144 16 55 -38 0 0 11 17 1 3 10 -17 144 3 6 144 30 46 143 40 27 144 53 29
144 31 34 -37 0 0 11 17 0 4 10 -17 144 17 54 144 45 14 143 55 32 145 7 40
144 46 21 -36 0 0 11 16 59 5 10 -18 144 32 51 144 59 52 144 10 44 145 22 2
145 1 18 -35 0 0 11 16 57 6 9 -19 144 47 58 145 14 40 144 26 6 145 36 35
145 16 26 -34 0 0 11 16 56 7 9 -20 145 3 13 145 29 38 144 41 36 145 51 20
145 31 43 -33 0 0 11 16 54 8 9 -21 145 18 39 145 44 48 144 57 15 146 6 16
145 47 12 -32 0 0 11 16 52 9 9 -21 145 34 15 146 0 9 145 13 4 146 21 24
146 2 51 -31 0 0 11 16 50 10 9 -22 145 50 2 146 15 41 145 29 3 146 36 44
146 18 42 -30 0 0 11 16 47 11 9 -23 146 6 0 146 31 25 145 45 12 146 52 17
146 34 45 -29 0 0 11 16 44 12 9 -24 146 22 10 146 47 22 146 1 32 147 8 3
146 51 1 -28 0 0 11 16 41 13 8 -25 146 38 31 147 3 31 146 18 4 147 24 2
147 7 29 -27 0 0 11 16 38 14 8 -26 146 55 5 147 19 53 146 34 47 147 40 15
147 24 10 -26 0 0 11 16 34 15 8 -26 147 11 51 147 36 28 146 51 42 147 56 41
147 41 4 -25 0 0 11 16 30 16 8 -27 147 28 51 147 53 18 147 8 50 148 13 22
147 58 12 -24 0 0 11 16 26 17 8 -28 147 46 4 148 10 21 147 26 11 148 30 18
148 15 35 -23 0 0 11 16 21 18 8 -29 148 3 31 148 27 39 147 43 45 148 47 29
148 33 12 -22 0 0 11 16 17 19 8 -30 148 21 12 148 45 12 148 1 33 149 4 55
148 51 4 -21 0 0 11 16 12 20 7 -31 148 39 8 149 3 0 148 19 36 149 22 37
149 9 12 -20 0 0 11 16 7 21 7 -31 148 57 19 149 21 5 148 37 53 149 40 35
149 27 35 -19 0 0 11 16 1 22 7 -32 149 15 46 149 39 25 148 56 25 149 58 50
149 46 15 -18 0 0 11 15 55 23 7 -33 149 34 29 149 58 2 149 15 13 150 17 23
Uncertainty in time = +/- 4 secs
Prediction of 2012 Dec 17.0
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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