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Updated: 2005 SEP 25, 18:45 UT
Event Rank : 33
(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 2005 Oct 27 UT, the 51 km diameter asteroid (1679) Nevanlinna will occult a 10.3 mag star in the constellation Monoceros for observers along a path running down the east coast of New Zealand. Although Dunedin is the only city inside the predicted path, the considerable uncertainty means that an occultation could occur anywhere in New Zealand, particularly in the east.
In the case of an occultation, the combined light of the asteroid and the star will drop by 6.4 mag to 16.7 mag (the magnitude of the asteroid) for at most 5.6 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Ron Stone, 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
162 13 43 -50 0 0 12 48 9 9 76 -27 160 46 37 163 33 28 151 27 23 168 11 1
165 1 15 -49 0 0 12 48 2 11 74 -28 163 49 32 166 8 41 157 39 52 170 12 50
167 18 24 -48 0 0 12 47 54 12 72 -29 166 16 1 168 17 54 161 16 5 171 58 29
169 14 49 -47 0 0 12 47 46 14 71 -30 168 18 50 170 8 40 163 59 18 173 31 30
170 55 49 -46 0 0 12 47 38 15 70 -31 170 4 35 171 45 23 166 12 19 174 54 14
172 24 44 -45 0 0 12 47 29 17 69 -32 171 37 12 173 10 55 168 4 53 176 8 25
173 43 48 -44 0 0 12 47 21 18 69 -33 172 59 14 174 27 15 169 42 22 177 15 17
174 54 39 -43 0 0 12 47 12 19 68 -33 174 12 33 175 35 48 171 8 2 178 15 50
175 58 29 -42 0 0 12 47 3 20 68 -34 175 18 26 176 37 42 172 24 5 179 10 51
176 56 14 -41 0 0 12 46 54 21 67 -35 176 17 57 177 33 47 173 32 8 -179 59 2
177 48 38 -40 0 0 12 46 45 22 67 -36 177 11 52 178 24 44 174 33 20 -179 13 20
178 36 17 -39 0 0 12 46 35 23 67 -37 178 0 51 179 11 7 175 28 35 -178 31 37
179 19 39 -38 0 0 12 46 26 24 67 -37 178 45 23 179 53 22 176 18 36 -177 53 30
179 59 9 -37 0 0 12 46 16 25 67 -38 179 25 56 -179 28 8 177 3 58 -177 18 41
-179 24 52 -36 0 0 12 46 6 26 67 -39 -179 57 9 -178 53 2 177 45 8 -176 46 55
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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