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Updated: 2007 JUN 26, 03:06 UT
Event Rank : 6
(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 Jul 25 UT, the 11 km diameter asteroid (4217) Engelhardt will occult a 8.1 mag star in the constellation Ara for observers along a very narrow, large uncertainty path across the southern end of New Zealand, passing near Invercargill, across Tasmania and mainland Australia.
In the case of an occultation, the combined light of the asteroid and the star will drop by 7.2 mag to 15.3 mag (the magnitude of the asteroid) for at most 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
121 0 5 -10 0 0 14 42 5 35 193 -68 121 4 4 120 56 6 122 37 6 119 25 12
121 21 29 -11 0 0 14 41 56 36 194 -69 121 25 30 121 17 28 122 59 15 119 45 53
121 43 57 -12 0 0 14 41 46 37 194 -70 121 48 0 121 39 54 123 22 33 120 7 34
122 7 31 -13 0 0 14 41 36 38 194 -70 122 11 37 122 3 27 123 47 2 120 30 19
122 32 15 -14 0 0 14 41 26 39 195 -71 122 36 23 122 28 8 124 12 45 120 54 8
122 58 11 -15 0 0 14 41 16 40 195 -72 123 2 21 122 54 1 124 39 44 121 19 5
123 25 22 -16 0 0 14 41 5 41 196 -72 123 29 34 123 21 9 125 8 4 121 45 12
123 53 51 -17 0 0 14 40 55 42 196 -73 123 58 6 123 49 35 125 37 47 122 12 33
124 23 41 -18 0 0 14 40 44 42 197 -74 124 28 0 124 19 22 126 8 57 122 41 10
124 54 57 -19 0 0 14 40 32 43 197 -74 124 59 19 124 50 35 126 41 40 123 11 7
125 0 0 -19 9 26 14 40 30 43 197 -74 -19 1 16 -19 17 34 -15 43 13 -22 17 34
126 0 0 -20 56 28 14 40 10 45 198 -75 -20 48 46 -21 4 9 -17 43 4 -23 54 48
127 0 0 -22 35 11 14 39 49 46 199 -76 -22 27 52 -22 42 28 -19 32 25 -25 25 5
128 0 0 -24 6 39 14 39 30 47 200 -76 -23 59 40 -24 13 36 -21 12 56 -26 49 15
129 0 0 -25 31 45 14 39 12 48 201 -77 -25 25 4 -25 38 25 -22 45 50 -28 7 56
130 0 0 -26 51 12 14 38 54 49 202 -77 -26 44 46 -26 57 36 -24 12 5 -29 21 41
131 0 0 -28 5 34 14 38 37 50 203 -77 -27 59 22 -28 11 45 -25 32 28 -30 30 57
132 0 0 -29 15 21 14 38 20 51 204 -77 -29 9 22 -29 21 20 -26 47 36 -31 36 9
133 0 0 -30 20 58 14 38 4 51 205 -76 -30 15 9 -30 26 45 -27 58 0 -32 37 36
134 0 0 -31 22 45 14 37 48 52 206 -76 -31 17 7 -31 28 23 -29 4 7 -33 35 37
135 0 0 -32 21 2 14 37 33 52 207 -76 -32 15 33 -32 26 30 -30 6 19 -34 30 26
136 0 0 -33 16 4 14 37 19 53 208 -75 -33 10 43 -33 21 24 -31 4 56 -35 22 17
137 0 0 -34 8 6 14 37 5 53 209 -75 -34 2 53 -34 13 18 -32 0 14 -36 11 23
138 0 0 -34 57 19 14 36 51 53 210 -74 -34 52 14 -35 2 25 -32 52 29 -36 57 55
139 0 0 -35 43 56 14 36 37 54 211 -74 -35 38 57 -35 48 55 -33 41 52 -37 42 1
140 0 0 -36 28 6 14 36 24 54 212 -73 -36 23 13 -36 32 59 -34 28 36 -38 23 52
141 0 0 -37 9 59 14 36 12 54 213 -72 -37 5 11 -37 14 46 -35 12 51 -39 3 34
142 0 0 -37 49 41 14 35 59 54 214 -72 -37 44 59 -37 54 23 -35 54 46 -39 41 15
143 0 0 -38 27 21 14 35 47 54 214 -71 -38 22 44 -38 31 58 -36 34 29 -40 17 2
144 0 0 -39 3 5 14 35 35 54 215 -71 -38 58 32 -39 7 37 -37 12 8 -40 51 0
145 0 0 -39 36 59 14 35 24 54 216 -70 -39 32 31 -39 41 27 -37 47 49 -41 23 16
146 0 0 -40 9 9 14 35 13 54 216 -69 -40 4 45 -40 13 33 -38 21 39 -41 53 53
147 0 0 -40 39 40 14 35 2 54 217 -69 -40 35 19 -40 44 0 -38 53 43 -42 22 57
148 0 0 -41 8 35 14 34 51 54 218 -68 -41 4 18 -41 12 52 -39 24 7 -42 50 31
149 0 0 -41 36 1 14 34 40 54 218 -67 -41 31 47 -41 40 14 -39 52 54 -43 16 41
150 0 0 -42 2 0 14 34 30 54 219 -67 -41 57 49 -42 6 10 -40 20 10 -43 41 28
151 0 0 -42 26 36 14 34 20 54 219 -66 -42 22 28 -42 30 43 -40 45 57 -44 4 57
152 0 0 -42 49 52 14 34 10 54 220 -66 -42 45 46 -42 53 57 -41 10 21 -44 27 10
153 0 0 -43 11 51 14 34 0 54 220 -65 -43 7 48 -43 15 54 -41 33 23 -44 48 10
154 0 0 -43 32 37 14 33 50 53 221 -64 -43 28 36 -43 36 37 -41 55 8 -45 8 1
155 0 0 -43 52 11 14 33 41 53 221 -64 -43 48 13 -43 56 9 -42 15 37 -45 26 43
156 0 0 -44 10 37 14 33 32 53 221 -63 -44 6 41 -44 14 32 -42 34 54 -45 44 21
157 0 0 -44 27 55 14 33 23 53 221 -63 -44 24 1 -44 31 49 -42 53 0 -46 0 54
158 0 0 -44 44 9 14 33 14 53 222 -62 -44 40 17 -44 48 1 -43 9 59 -46 16 26
159 0 0 -44 59 20 14 33 5 52 222 -62 -44 55 30 -45 3 11 -43 25 51 -46 30 58
160 0 0 -45 13 30 14 32 56 52 222 -61 -45 9 41 -45 17 19 -43 40 40 -46 44 32
161 0 0 -45 26 41 14 32 48 52 222 -60 -45 22 53 -45 30 28 -43 54 25 -46 57 9
162 0 0 -45 38 53 14 32 39 51 222 -60 -45 35 7 -45 42 39 -44 7 10 -47 8 50
163 0 0 -45 50 8 14 32 31 51 222 -59 -45 46 23 -45 53 53 -44 18 56 -47 19 37
164 0 0 -46 0 28 14 32 23 51 223 -59 -45 56 44 -46 4 12 -44 29 43 -47 29 31
165 0 0 -46 9 53 14 32 15 50 223 -58 -46 6 10 -46 13 36 -44 39 32 -47 38 33
166 0 0 -46 18 25 14 32 7 50 223 -58 -46 14 43 -46 22 7 -44 48 26 -47 46 43
167 0 0 -46 26 4 14 31 59 50 223 -57 -46 22 22 -46 29 45 -44 56 24 -47 54 3
168 0 0 -46 32 50 14 31 51 49 223 -57 -46 29 10 -46 36 31 -45 3 29 -48 0 33
169 0 0 -46 38 46 14 31 43 49 222 -56 -46 35 6 -46 42 26 -45 9 39 -48 6 15
170 0 0 -46 43 50 14 31 35 49 222 -55 -46 40 11 -46 47 30 -45 14 56 -48 11 7
171 0 0 -46 48 5 14 31 28 48 222 -55 -46 44 26 -46 51 44 -45 19 21 -48 15 12
172 0 0 -46 51 30 14 31 20 48 222 -54 -46 47 51 -46 55 8 -45 22 54 -48 18 28
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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