|
|
Updated: 2008 JAN 02, 23:48 UT
Event Rank : 10
(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 Jan 10 UT, the 11 km diameter asteroid (9117) Aude will occult a 9.0 mag star in the constellation Gemini for observers along a narrow, significant uncertainty path across northern and central Australia.
In the case of an occultation, the combined light of the asteroid and the star will drop by 5.8 mag to 14.8 mag (the magnitude of the asteroid) for at most only 1.2 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
140 0 3 -25 0 0 19 40 48 9 307 -5 140 5 29 139 54 37 141 15 33 138 45 34
138 34 13 -24 0 0 19 40 51 10 307 -6 138 39 32 138 28 55 139 47 58 137 21 25
137 11 1 -23 0 0 19 40 55 12 308 -8 137 16 13 137 5 49 138 23 10 135 59 43
135 50 12 -22 0 0 19 40 59 13 308 -10 135 55 17 135 45 6 137 0 53 134 40 16
134 31 32 -21 0 0 19 41 4 15 309 -11 134 36 32 134 26 32 135 40 54 133 22 52
133 14 52 -20 0 0 19 41 9 17 309 -13 133 19 47 133 9 57 134 23 1 132 7 20
131 59 59 -19 0 0 19 41 15 18 309 -14 132 4 50 131 55 9 133 7 3 130 53 30
130 46 46 -18 0 0 19 41 21 20 310 -16 130 51 32 130 42 0 131 52 49 129 41 15
129 35 4 -17 0 0 19 41 28 21 310 -17 129 39 46 129 30 22 130 40 11 128 30 25
128 24 45 -16 0 0 19 41 35 23 310 -18 128 29 23 128 20 6 129 29 2 127 20 54
127 15 42 -15 0 0 19 41 42 24 311 -20 127 20 17 127 11 7 128 19 12 126 12 36
126 7 49 -14 0 0 19 41 49 25 311 -21 126 12 21 126 3 17 127 10 37 125 5 23
125 1 0 -13 0 0 19 41 57 27 311 -23 125 5 30 124 56 31 126 3 9 123 59 11
123 55 10 -12 0 0 19 42 6 28 311 -24 123 59 37 123 50 43 124 56 44 122 53 55
122 50 13 -11 0 0 19 42 15 30 312 -26 122 54 38 122 45 48 123 51 14 121 49 29
121 46 5 -10 0 0 19 42 24 31 312 -27 121 50 27 121 41 42 122 46 37 120 45 48
Use these links for further information:
[Planetary Occultations]
[Using the Predictions]
[Observing Details]
[Timing Details]
[Reporting Details]
[Report Form]
[Asteroid Occultation Results]
[Top of Page][Return to Home Page]