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Updated: 2021 Jul 15, 17:52 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 2021 Aug 31 UT, the 70 km diameter asteroid (1264) Letaba will occult a 11.4 mag star in the constellation Vulpecula for observers along a path across southern Tasmania.
In the case of an occultation, the combined light of the asteroid and the star will drop by 2.50 mag to 13.82 mag (the magnitude of the asteroid) for at most 6.7 seconds.
This update is based on, astrometry for the asteroid kindly provided by the IAU Minor Planet Center. This work has made use of data from the European Space Agency (ESA) mission Gaia (http://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, http://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.
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.
Occultation of TYC 2172-00726-1 by 1264 Letaba on 2021 Aug 31
Centre Star Star Sun Path Limits Error Limits Alt
E. Longitude Latitude U.T. Alt Az Alt Limit 1 Limit 2 Limit 3 Limit 4 Crn
o ' " o ' " h m s o o o o ' " o ' " o ' " o ' "
Longitude Longitude Longitude Longitude
144 2 30 -45 0 0 9 56 23.9 12 39 -22 143 24 58 144 39 52 143 14 14 144 50 30 0.25
145 17 14 -44 0 0 9 56 20.7 13 38 -23 144 40 37 145 53 42 144 30 9 146 4 5 0.25
146 29 32 -43 0 0 9 56 17.2 15 37 -24 145 53 46 147 5 11 145 43 32 147 15 20 0.26
147 39 37 -42 0 0 9 56 13.5 16 36 -25 147 4 38 148 14 31 146 54 38 148 24 27 0.26
148 47 42 -41 0 0 9 56 9.4 17 35 -26 148 13 26 149 21 53 148 3 38 149 31 37 0.26
149 53 57 -40 0 0 9 56 5.1 19 35 -27 149 20 20 150 27 28 149 10 44 150 37 1 0.26
150 58 30 -39 0 0 9 56 0.5 20 34 -28 150 25 31 151 31 24 150 16 6 151 40 47 0.27
152 1 31 -38 0 0 9 55 55.6 21 33 -29 151 29 7 152 33 51 151 19 51 152 43 4 0.27
153 3 7 -37 0 0 9 55 50.5 22 33 -30 152 31 15 153 34 55 152 22 9 153 43 59 0.27
154 3 26 -36 0 0 9 55 45.1 24 32 -31 153 32 4 154 34 44 153 23 7 154 43 40 0.27
155 2 33 -35 0 0 9 55 39.4 25 31 -32 154 31 40 155 33 24 154 22 51 155 42 12 0.27
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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