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Updated: 2010 OCT 03, 20:34 UT
Event Rank : 100
(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 2010 Nov 05 UT, the 256 km diameter asteroid (31) Euphrosyne will occult a 7.6 mag star in the constellation Grus for observers along a south-to-north path just skimming the east coast of Australia from Forster in NSW, to Maryborough in QLD.
In the case of an occultation, the combined light of the asteroid and the star will drop by 5.2 mag to 12.8 mag (the magnitude of the asteroid) for at most 13.8 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: .
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
154 32 57 -35 43 54 10 58 45 61 253 -28 152 57 30 -35 49 11 156 9 18 -35 37 3 152 29 3 -35 50 29 156 38 23 -35 34 42
154 30 1 -34 24 52 10 58 53 61 251 -29 152 56 1 -34 30 10 156 4 55 -34 18 1 152 28 0 -34 31 28 156 33 34 -34 15 40
154 28 15 -33 5 29 10 59 1 60 249 -30 152 55 36 -33 10 49 156 1 48 -32 58 37 152 27 59 -33 12 8 156 30 3 -32 56 15
154 27 37 -31 45 42 10 59 8 60 247 -31 152 56 14 -31 51 7 155 59 56 -31 38 48 152 28 59 -31 52 27 156 27 48 -31 36 25
154 28 6 -30 25 30 10 59 16 59 244 -32 152 57 53 -30 30 58 155 59 15 -30 18 30 152 30 59 -30 32 20 156 26 47 -30 16 6
154 29 40 -29 4 47 10 59 24 59 243 -33 153 0 31 -29 10 22 155 59 45 -28 57 42 152 33 57 -29 11 45 156 26 57 -28 55 16
154 32 18 -27 43 31 10 59 32 58 241 -34 153 4 9 -27 49 13 156 1 24 -27 36 19 152 37 53 -27 50 39 156 28 19 -27 33 51
154 36 1 -26 21 38 10 59 40 57 239 -35 153 8 46 -26 27 30 156 4 12 -26 14 17 152 42 46 -26 28 58 156 30 51 -26 11 47
154 40 47 -24 59 5 10 59 48 56 237 -36 153 14 22 -25 5 7 156 8 9 -24 51 34 152 48 37 -25 6 38 156 34 34 -24 49 0
154 46 37 -23 35 47 10 59 55 55 235 -37 153 20 57 -23 42 1 156 13 15 -23 28 4 152 55 26 -23 43 35 156 39 27 -23 25 26
154 53 32 -22 11 40 11 0 3 55 234 -38 153 28 33 -22 18 7 156 19 31 -22 3 43 153 3 14 -22 19 46 156 45 31 -22 1 1
155 1 34 -20 46 39 11 0 11 54 232 -39 153 37 11 -20 53 21 156 26 59 -20 38 25 153 12 3 -20 55 4 156 52 49 -20 35 39
155 10 45 -19 20 38 11 0 19 53 231 -40 153 46 53 -19 27 37 156 35 40 -19 12 7 153 21 54 -19 29 25 157 1 21 -19 9 14
155 21 6 -17 53 32 11 0 27 51 230 -42 153 57 40 -18 0 49 156 45 36 -17 44 40 153 32 50 -18 2 43 157 11 10 -17 41 41
155 32 41 -16 25 14 11 0 35 50 228 -43 154 9 37 -16 32 52 156 56 52 -16 15 59 153 44 54 -16 34 52 157 22 21 -16 12 53
Uncertainty in time = +/- 2 secs
Prediction of 2010 Oct 4.0
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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