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Updated: 2007 MAR 09, 23:14 UT
Event Rank : 99
(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 2007 Mar 16 UT, the 157 km diameter asteroid (139) Juewa will occult a 11.5 mag star in the constellation Scorpius for observers along a wide path across southern Western Australia, from Learmonth to Kalgoorlie.
In the case of an occultation, the combined light of the asteroid and the star will drop by 1.5 mag to 12.7 mag (the magnitude of the asteroid) for at most 10.0 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 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
... .. .. .. .. .. .. .. .. .. .. .. ... .. .. .. .. .. ... .. .. .. .. .. 108 42 8 -15 22 20 ... .. .. .. .. ..
106 55 12 -16 7 24 16 1 27 2 124 -67 112 3 38 -18 45 20 ... .. .. .. .. .. 114 3 30 -19 33 58 ... .. .. .. .. ..
112 46 39 -20 40 32 16 1 34 9 122 -66 115 29 6 -21 39 11 109 4 51 -19 1 15 116 58 47 -22 6 51 ... .. .. .. .. ..
115 43 26 -23 15 31 16 1 42 13 121 -64 117 55 57 -23 52 59 113 10 1 -22 23 29 119 13 25 -24 11 49 111 13 4 -21 37 12
117 57 53 -25 21 26 16 1 49 16 120 -63 119 55 50 -25 48 7 115 47 48 -24 46 11 121 6 29 -26 1 46 114 15 38 -24 17 21
119 50 13 -27 11 59 16 1 57 18 119 -61 121 39 25 -27 31 49 117 52 34 -26 46 6 122 45 41 -27 41 56 116 31 36 -26 25 31
121 28 28 -28 52 37 16 2 4 20 118 -59 123 11 50 -29 7 36 119 38 35 -28 32 58 124 15 6 -29 15 8 118 24 7 -28 17 25
122 56 47 -30 26 12 16 2 11 22 117 -58 124 36 4 -30 37 30 121 12 11 -30 11 4 125 37 10 -30 43 0 120 1 57 -29 59 1
124 17 40 -31 54 27 16 2 19 24 115 -56 125 53 58 -32 2 49 122 36 48 -31 42 48 126 53 28 -32 6 40 121 29 31 -31 33 23
125 32 43 -33 18 28 16 2 26 26 114 -55 127 6 49 -33 24 26 123 54 35 -33 9 38 128 5 9 -33 26 55 122 49 25 -33 2 17
126 43 5 -34 39 4 16 2 34 27 113 -53 128 15 35 -34 43 0 125 6 58 -34 32 34 129 13 2 -34 44 17 124 3 20 -34 26 53
127 49 36 -35 56 49 16 2 41 28 112 -52 129 20 55 -35 58 58 126 14 57 -35 52 17 130 17 44 -35 59 14 125 12 26 -35 48 2
128 52 54 -37 12 8 16 2 49 30 111 -51 130 23 23 -37 12 45 127 19 17 -37 9 20 131 19 45 -37 12 6 126 17 35 -37 6 18
129 53 27 -38 25 24 16 2 56 31 110 -49 131 23 23 -38 24 38 128 20 33 -38 24 7 132 19 29 -38 23 10 127 19 25 -38 22 8
130 51 40 -39 36 51 16 3 3 32 109 -48 132 21 18 -39 34 51 129 19 12 -39 36 56 133 17 15 -39 32 38 128 18 25 -39 35 53
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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