|
|
Updated: 2008 MAR 07, 13:40 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 2008 Apr 03 UT, the 216 km diameter asteroid (375) Ursula will occult a 10.9 mag star in the constellation Scorpius for observers along a very wide path across western parts of Western Australia, including Perth.
In the case of an occultation, the combined light of the asteroid and the star will drop by 2.0 mag to 12.7 mag (the magnitude of the asteroid) for at most 23.0 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: 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
114 42 4 -12 30 37 14 12 41 3 133 -57 120 45 45 -17 28 47 ... .. .. .. .. .. 122 50 48 -19 0 59 ... .. .. .. .. ..
115 37 12 -13 58 12 14 12 47 5 133 -57 120 54 51 -18 13 16 ... .. .. .. .. .. 122 55 31 -19 41 15 ... .. .. .. .. ..
116 11 28 -15 6 29 14 12 52 6 132 -58 121 1 48 -18 55 52 ... .. .. .. .. .. 122 58 45 -20 20 18 ... .. .. .. .. ..
116 35 40 -16 5 29 14 12 57 7 132 -58 121 6 52 -19 36 51 ... .. .. .. .. .. 123 0 39 -20 58 15 ... .. .. .. .. ..
116 53 29 -16 58 41 14 13 3 8 132 -58 121 10 15 -20 16 25 ... .. .. .. .. .. 123 1 18 -21 35 12 ... .. .. .. .. ..
117 6 45 -17 47 47 14 13 8 8 132 -58 121 12 8 -20 54 44 ... .. .. .. .. .. 123 0 48 -22 11 13 ... .. .. .. .. ..
117 16 30 -18 33 44 14 13 14 9 132 -58 121 12 37 -21 31 55 ... .. .. .. .. .. 122 59 14 -22 46 23 ... .. .. .. .. ..
117 23 24 -19 17 11 14 13 19 10 132 -58 121 11 51 -22 8 5 ... .. .. .. .. .. 122 56 37 -23 20 46 ... .. .. .. .. ..
117 27 54 -19 58 34 14 13 25 10 132 -58 121 9 53 -22 43 18 ... .. .. .. .. .. 122 53 3 -23 54 25 ... .. .. .. .. ..
117 30 21 -20 38 10 14 13 30 11 131 -57 121 6 48 -23 17 39 111 0 48 -15 11 59 122 48 32 -24 27 22 ... .. .. .. .. ..
117 30 58 -21 16 14 14 13 36 11 131 -57 121 2 40 -23 51 11 111 45 36 -16 31 39 122 43 8 -24 59 40 ... .. .. .. .. ..
117 29 58 -21 52 57 14 13 41 12 131 -57 120 57 32 -24 23 58 112 10 52 -17 33 6 122 36 52 -25 31 21 ... .. .. .. .. ..
117 27 28 -22 28 27 14 13 47 12 131 -57 120 51 26 -24 56 2 112 26 53 -18 26 3 122 29 46 -26 2 26 ... .. .. .. .. ..
117 23 36 -23 2 51 14 13 52 12 131 -56 120 44 24 -25 27 26 112 37 4 -19 13 40 122 21 51 -26 32 58 ... .. .. .. .. ..
117 18 27 -23 36 14 14 13 57 13 131 -56 120 36 29 -25 58 11 112 43 1 -19 57 30 122 13 8 -27 2 56 ... .. .. .. .. ..
117 12 6 -24 8 40 14 14 3 13 131 -56 120 27 42 -26 28 20 112 45 42 -20 38 25 122 3 38 -27 32 24 ... .. .. .. .. ..
117 4 36 -24 40 15 14 14 8 13 131 -55 120 18 3 -26 57 53 112 45 41 -21 16 59 121 53 22 -28 1 21 107 46 36 -16 54 34
116 56 2 -25 11 0 14 14 14 13 131 -55 120 7 35 -27 26 52 112 43 23 -21 53 35 121 42 21 -28 29 48 108 28 48 -18 13 18
116 46 25 -25 40 58 14 14 19 14 131 -55 119 56 19 -27 55 18 112 39 4 -22 28 29 121 30 36 -28 57 47 108 47 30 -19 9 56
116 35 47 -26 10 12 14 14 25 14 131 -54 119 44 14 -28 23 12 112 32 58 -23 1 52 121 18 6 -29 25 17 108 56 42 -19 57 46
116 24 11 -26 38 44 14 14 30 14 131 -54 119 31 21 -28 50 35 112 25 14 -23 33 56 121 4 52 -29 52 21 109 0 7 -20 40 17
116 11 38 -27 6 34 14 14 36 14 131 -54 119 17 42 -29 17 28 112 15 59 -24 4 45 120 50 54 -30 18 57 108 59 24 -21 19 4
115 58 8 -27 33 45 14 14 41 14 131 -53 119 3 16 -29 43 51 112 5 19 -24 34 26 120 36 13 -30 45 7 108 55 25 -21 54 59
115 43 44 -28 0 18 14 14 47 15 131 -53 118 48 4 -30 9 44 111 53 19 -25 3 4 120 20 49 -31 10 50 108 48 46 -22 28 32
115 28 26 -28 26 13 14 14 52 15 131 -52 118 32 6 -30 35 9 111 40 2 -25 30 42 120 4 41 -31 36 8 108 39 48 -23 0 5
115 12 14 -28 51 31 14 14 57 15 131 -52 118 15 22 -31 0 5 111 25 31 -25 57 22 119 47 49 -32 1 0 108 28 46 -23 29 52
114 55 10 -29 16 13 14 15 3 15 131 -52 117 57 52 -31 24 32 111 9 49 -26 23 7 119 30 14 -32 25 26 108 15 52 -23 58 4
114 37 12 -29 40 19 14 15 8 15 131 -51 117 39 35 -31 48 31 110 52 58 -26 47 59 119 11 56 -32 49 27 108 1 13 -24 24 48
114 18 22 -30 3 49 14 15 14 15 131 -51 117 20 33 -32 12 2 110 34 58 -27 11 59 118 52 53 -33 13 2 107 44 55 -24 50 9
113 58 40 -30 26 44 14 15 19 15 131 -50 117 0 44 -32 35 4 110 15 51 -27 35 8 118 33 6 -33 36 11 107 27 2 -25 14 12
113 38 5 -30 49 4 14 15 25 15 131 -50 116 40 9 -32 57 39 109 55 37 -27 57 26 118 12 35 -33 58 55 107 7 37 -25 36 58
113 16 37 -31 10 49 14 15 30 15 131 -49 116 18 47 -33 19 45 109 34 17 -28 18 53 117 51 19 -34 21 14 106 46 42 -25 58 30
112 54 16 -31 31 57 14 15 36 15 131 -49 115 56 38 -33 41 22 109 11 50 -28 39 30 117 29 18 -34 43 6 106 24 18 -26 18 48
112 31 2 -31 52 30 14 15 41 15 131 -49 115 33 41 -34 2 30 108 48 17 -28 59 16 117 6 30 -35 4 31 106 0 24 -26 37 51
112 6 55 -32 12 27 14 15 47 15 131 -48 115 9 56 -34 23 9 108 23 36 -29 18 11 116 42 57 -35 25 30 105 35 0 -26 55 39
111 41 53 -32 31 46 14 15 52 15 131 -48 114 45 22 -34 43 18 107 57 48 -29 36 13 116 18 37 -35 46 2 105 8 4 -27 12 8
111 15 56 -32 50 28 14 15 57 15 131 -47 114 19 59 -35 2 57 107 30 51 -29 53 22 115 53 30 -36 6 7 104 39 33 -27 27 17
110 49 4 -33 8 31 14 16 3 15 131 -47 113 53 46 -35 22 5 107 2 43 -30 9 35 115 27 35 -36 25 44 104 9 24 -27 40 59
110 21 15 -33 25 55 14 16 8 15 131 -46 113 26 43 -35 40 41 106 33 23 -30 24 50 115 0 51 -36 44 52 103 37 30 -27 53 11
109 52 28 -33 42 39 14 16 14 15 131 -46 112 58 48 -35 58 46 106 2 49 -30 39 6 114 33 17 -37 3 31 103 3 45 -28 3 43
109 22 43 -33 58 41 14 16 19 15 132 -45 112 30 1 -36 16 17 105 30 58 -30 52 19 114 4 54 -37 21 39 102 27 59 -28 12 24
108 51 58 -34 13 59 14 16 25 14 132 -45 112 0 22 -36 33 14 104 57 48 -31 4 25 113 35 40 -37 39 18 101 49 59 -28 19 2
108 20 12 -34 28 33 14 16 30 14 132 -44 111 29 48 -36 49 37 104 23 13 -31 15 21 113 5 34 -37 56 24 101 9 27 -28 23 16
107 47 24 -34 42 21 14 16 36 14 132 -44 110 58 19 -37 5 23 103 47 11 -31 25 0 112 34 36 -38 12 59 100 25 56 -28 24 37
107 13 31 -34 55 19 14 16 41 14 132 -43 110 25 55 -37 20 32 103 9 35 -31 33 17 112 2 44 -38 28 59 99 38 43 -28 22 22
Uncertainty in time = +/- 7 secs
[Prediction of 2008 Mar 7.0]
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]