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Updated: 2009 JUN 11, 21:57 UT
Event Rank : 36
(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 2009 Jun 19 UT, the 54 km diameter asteroid (269) Justitia will occult a 13.1 mag star in the constellation Virgo for observers along a narrow path across the southwestern tip of the South Island of New Zealand.
In the case of an occultation, the combined light of the asteroid and the star will drop by 0.7 mag to 13.0 mag (the magnitude of the asteroid) for at most 20.8 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.
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
168 16 18 -33 47 50 7 0 31 48 55 -15 168 37 47 -33 40 52 167 54 40 -33 54 48 169 55 9 -33 15 17 166 34 6 -34 20 15
168 19 7 -34 56 51 7 1 19 47 54 -16 168 40 57 -34 49 47 167 57 8 -35 3 54 169 59 30 -34 23 54 166 35 14 -35 29 40
168 21 2 -36 6 37 7 2 7 47 52 -16 168 43 14 -35 59 28 167 58 40 -36 13 46 170 3 6 -35 33 16 166 35 19 -36 39 51
168 22 0 -37 17 12 7 2 55 46 51 -17 168 44 36 -37 9 58 167 59 13 -37 24 26 170 5 53 -36 43 24 166 34 17 -37 50 53
168 21 58 -38 28 40 7 3 43 45 50 -17 168 45 0 -38 21 19 167 58 44 -38 36 0 170 7 50 -37 54 24 166 32 4 -39 2 49
168 20 50 -39 41 4 7 4 31 45 49 -18 168 44 22 -39 33 37 167 57 7 -39 48 31 170 8 52 -39 6 18 166 28 33 -40 15 44
168 18 32 -40 54 30 7 5 19 44 48 -18 168 42 35 -40 46 56 167 54 17 -41 2 4 170 8 56 -40 19 12 166 23 39 -41 29 42
168 14 58 -42 9 1 7 6 7 43 47 -19 168 39 36 -42 1 20 167 50 6 -42 16 43 170 7 57 -41 33 9 166 17 11 -42 44 48
168 9 58 -43 24 44 7 6 56 42 46 -19 168 35 15 -43 16 55 167 44 28 -43 32 33 170 5 49 -42 48 15 166 9 1 -44 1 8
168 3 25 -44 41 44 7 7 44 42 45 -19 168 29 24 -44 33 46 167 37 12 -44 49 42 170 2 25 -44 4 36 165 58 57 -45 18 48
167 55 7 -46 0 8 7 8 32 41 44 -20 168 21 53 -45 52 1 167 28 5 -46 8 15 169 57 36 -45 22 17 165 46 43 -46 37 54
167 44 50 -47 20 3 7 9 20 40 43 -20 168 12 28 -47 11 46 167 16 54 -47 28 20 169 51 13 -46 41 26 165 32 3 -47 58 35
167 32 17 -48 41 38 7 10 8 39 42 -20 168 0 54 -48 33 10 167 3 21 -48 50 5 169 43 1 -48 2 11 165 14 34 -49 21 0
Uncertainty in time = +/- 40 secs
Prediction of 2009 Jun 12.0
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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