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Updated: 2013 JAN 26, 17:20 UT
Event Rank : 37
(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 Feb 26 UT, the 36 km diameter asteroid (2091) Sampo will occult a 11.4 mag star in the constellation Gemini for observers along a path near Invercargill, New Zealand
In the case of an occultation, the combined light of the asteroid and the star will drop by 3.7 mag to 15.1 mag (the magnitude of the asteroid) for at most 6.7 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 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
169 7 4 -64 0 0 9 13 48 1 11 -6 169 50 55 168 22 43 ... .. .. 165 39 37
169 28 41 -63 0 0 9 13 49 2 11 -7 170 10 51 168 46 4 ... .. .. 166 9 33
169 44 56 -62 0 0 9 13 50 3 11 -8 170 25 36 169 3 52 ... .. .. 166 33 12
169 56 23 -61 0 0 9 13 52 4 11 -8 170 35 42 169 16 42 ... .. .. 166 51 15
170 3 31 -60 0 0 9 13 55 5 10 -9 170 41 36 169 25 4 ... .. .. 167 4 19
170 6 42 -59 0 0 9 13 59 6 10 -10 170 43 41 169 29 22 ... .. .. 167 12 50
170 6 17 -58 0 0 9 14 3 7 10 -10 170 42 16 169 29 58 172 48 44 167 17 15
170 2 33 -57 0 0 9 14 8 8 10 -11 170 37 38 169 27 10 172 40 57 167 17 53
169 55 44 -56 0 0 9 14 14 9 11 -11 170 29 59 169 21 11 172 30 27 167 15 3
169 46 3 -55 0 0 9 14 20 10 11 -12 170 19 33 169 12 16 172 17 24 167 8 58
169 33 41 -54 0 0 9 14 27 11 11 -12 170 6 30 169 0 36 172 1 58 166 59 52
169 18 46 -53 0 0 9 14 35 12 11 -13 169 50 57 168 46 19 171 44 15 166 47 55
169 1 26 -52 0 0 9 14 43 13 11 -13 169 33 4 168 29 34 171 24 23 166 33 17
168 41 49 -51 0 0 9 14 52 14 12 -14 169 12 55 168 10 27 171 2 26 166 16 6
168 19 59 -50 0 0 9 15 2 14 12 -14 168 50 37 167 49 6 170 38 31 165 56 28
167 56 1 -49 0 0 9 15 13 15 12 -14 168 26 14 167 25 33 170 12 39 165 34 29
167 29 59 -48 0 0 9 15 24 16 13 -15 167 59 50 166 59 54 169 44 55 165 10 13
167 1 56 -47 0 0 9 15 36 17 13 -15 167 31 27 166 32 11 169 15 21 164 43 44
166 31 54 -46 0 0 9 15 48 18 14 -15 167 1 7 166 2 28 168 43 58 164 15 4
165 59 56 -45 0 0 9 16 2 19 14 -15 166 28 54 165 30 45 168 10 50 163 44 17
165 26 2 -44 0 0 9 16 16 20 15 -15 165 54 46 164 57 4 167 35 55 163 11 23
164 50 12 -43 0 0 9 16 31 21 16 -16 165 18 46 164 21 25 166 59 14 162 36 24
164 12 28 -42 0 0 9 16 46 22 16 -16 164 40 52 163 43 49 166 20 48 161 59 18
163 32 47 -41 0 0 9 17 2 22 17 -16 164 1 5 163 4 15 165 40 36 161 20 6
162 51 9 -40 0 0 9 17 20 23 18 -16 163 19 23 162 22 42 164 58 36 160 38 46
Uncertainty in time = +/- 14 secs
Prediction of 2013 Jan 27.0
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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