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Updated: 2008 APR 09, 00:02 UT
Event Rank : 12
(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 Apr 17 UT, the 28 km diameter asteroid (1277) Dolores will occult a 7.3 mag star in the constellation Leo for observers along a large uncertainty path across New Zealand, centred on Hastings to Auckland.
In the case of an occultation, the combined light of the asteroid and the star will drop by 8.3 mag to 15.6 mag (the magnitude of the asteroid) for at most 3.4 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
179 22 0 -43 13 36 7 9 58 41 45 -20 179 9 24 -43 20 17 179 34 31 -43 6 55 176 46 26 -44 33 19 -178 14 48 -41 54 53
178 43 20 -42 18 46 7 10 11 41 47 -19 178 30 53 -42 25 21 178 55 41 -42 12 11 176 9 55 -43 37 21 -178 55 11 -41 1 6
178 4 29 -41 24 34 7 10 25 42 48 -19 177 52 12 -41 31 5 178 16 42 -41 18 5 175 33 4 -42 42 6 -179 35 36 -40 7 55
177 25 28 -40 31 0 7 10 38 42 49 -18 177 13 19 -40 37 25 177 37 33 -40 24 35 174 55 52 -41 47 30 179 43 54 -39 15 17
176 46 14 -39 37 59 7 10 52 42 50 -18 176 34 13 -39 44 20 176 58 11 -39 31 39 174 18 19 -40 53 31 179 3 19 -38 23 11
176 6 47 -38 45 31 7 11 5 42 52 -17 175 54 52 -38 51 47 176 18 37 -38 39 15 173 40 25 -40 0 8 178 22 37 -37 31 35
175 27 5 -37 53 33 7 11 19 42 53 -17 175 15 17 -37 59 45 175 38 49 -37 47 22 173 2 8 -39 7 17 177 41 46 -36 40 26
174 47 7 -37 2 5 7 11 32 43 54 -17 174 35 25 -37 8 12 174 58 45 -36 55 57 172 23 27 -38 14 58 177 0 44 -35 49 45
174 6 51 -36 11 3 7 11 45 43 55 -16 173 55 14 -36 17 7 174 18 23 -36 5 0 171 44 22 -37 23 9 176 19 30 -34 59 28
173 26 16 -35 20 27 7 11 59 43 57 -15 173 14 44 -35 26 27 173 37 44 -35 14 28 171 4 52 -36 31 47 175 38 3 -34 9 35
172 45 21 -34 30 16 7 12 12 43 58 -15 172 33 53 -34 36 12 172 56 44 -34 24 20 170 24 54 -35 40 52 174 56 20 -33 20 5
172 4 3 -33 40 27 7 12 26 43 59 -14 171 52 40 -33 46 20 172 15 23 -33 34 35 169 44 29 -34 50 21 174 14 19 -32 30 56
171 22 22 -32 51 0 7 12 39 43 60 -14 171 11 3 -32 56 50 171 33 38 -32 45 11 169 3 34 -34 0 14 173 32 0 -31 42 7
Uncertainty in time = +/- 18 secs
[Prediction of 2008 Apr 9.0]
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[Planetary Occultations]
[Using the Predictions]
[Observing Details]
[Timing Details]
[Reporting Details]
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[Asteroid Occultation Results]
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