|
|
Updated: 2019 JUL 21, 05:52 UT
Event Rank : 33
(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 2019 Sep 27 UT, the 73 km diameter asteroid (7641) 1986 TT6 will occult a 11.8 mag star in the constellation Sagitta for observers along a narrow path of significant uncertainty across western Western Australia from Marble Bar to east of Albany.
In the case of an occultation, the combined light of the asteroid and the star will drop by 5.44 mag to 17.23 mag (the magnitude of the asteroid) for at most 5.3 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.
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
118 43 24 -39 0 0 12 42 0 30 349 -30 118 16 46 119 10 6 115 53 32 121 35 28 -0.33
118 43 34 -38 0 0 12 41 56 31 349 -30 118 17 17 119 9 53 115 56 1 121 33 14 0.33
118 44 11 -37 0 0 12 41 52 32 349 -31 118 18 15 119 10 9 115 58 50 121 31 36 0.33
118 45 14 -36 0 0 12 41 47 33 349 -31 118 19 39 119 10 53 116 1 59 121 30 32 0.33
118 46 44 -35 0 0 12 41 43 33 349 -32 118 21 27 119 12 4 116 5 27 121 29 59 0.33
118 48 38 -34 0 0 12 41 38 34 348 -32 118 23 39 119 13 40 116 9 14 121 29 58 0.33
118 50 56 -33 0 0 12 41 33 35 348 -33 118 26 14 119 15 42 116 13 20 121 30 26 0.33
118 53 38 -32 0 0 12 41 28 36 348 -33 118 29 11 119 18 7 116 17 43 121 31 24 0.33
118 56 42 -31 0 0 12 41 23 37 348 -34 118 32 31 119 20 56 116 22 23 121 32 49 0.33
119 0 8 -30 0 0 12 41 18 38 348 -34 118 36 11 119 24 7 116 27 21 121 34 42 0.33
119 3 55 -29 0 0 12 41 13 39 347 -35 118 40 12 119 27 41 116 32 36 121 37 1 0.33
119 8 4 -28 0 0 12 41 7 40 347 -35 118 44 34 119 31 36 116 38 6 121 39 45 0.33
119 12 33 -27 0 0 12 41 2 41 347 -35 118 49 15 119 35 53 116 43 53 121 42 55 0.33
119 17 21 -26 0 0 12 40 56 42 347 -36 118 54 15 119 40 30 116 49 56 121 46 28 0.33
119 22 30 -25 0 0 12 40 51 43 346 -36 118 59 35 119 45 28 116 56 14 121 50 26 0.33
119 27 58 -24 0 0 12 40 45 44 346 -37 119 5 13 119 50 46 117 2 48 121 54 47 0.33
119 33 45 -23 0 0 12 40 39 45 346 -37 119 11 10 119 56 23 117 9 37 121 59 32 0.33
119 39 51 -22 0 0 12 40 33 46 345 -38 119 17 25 120 2 20 117 16 41 122 4 38 0.33
119 46 15 -21 0 0 12 40 27 47 345 -38 119 23 58 120 8 35 117 24 0 122 10 8 0.33
119 52 58 -20 0 0 12 40 21 48 345 -38 119 30 49 120 15 10 117 31 34 122 15 59 0.33
120 0 0 -19 0 0 12 40 14 49 344 -39 119 37 57 120 22 4 117 39 23 122 22 11 0.33
120 7 19 -18 0 0 12 40 8 50 344 -39 119 45 24 120 29 16 117 47 27 122 28 46 0.33
120 14 56 -17 0 0 12 40 2 51 343 -40 119 53 8 120 36 47 117 55 46 122 35 42 0.33
120 22 52 -16 0 0 12 39 55 52 343 -40 120 1 9 120 44 37 118 4 20 122 42 59 0.33
120 31 5 -15 0 0 12 39 48 53 342 -40 120 9 28 120 52 45 118 13 9 122 50 37 0.33
120 39 37 -14 0 0 12 39 42 53 342 -41 120 18 5 121 1 11 118 22 12 122 58 36 0.33
120 48 26 -13 0 0 12 39 35 54 341 -41 120 26 59 121 9 56 118 31 31 123 6 56 0.33
120 57 34 -12 0 0 12 39 28 55 340 -41 120 36 10 121 19 0 118 41 5 123 15 38 0.33
121 7 0 -11 0 0 12 39 21 56 340 -42 120 45 40 121 28 22 118 50 54 123 24 40 0.33
121 16 44 -10 0 0 12 39 14 57 339 -42 120 55 27 121 38 3 119 0 59 123 34 4 0.33
121 26 46 - 9 0 0 12 39 7 58 338 -42 121 5 32 121 48 2 119 11 19 123 43 49 0.32
121 37 7 - 8 0 0 12 38 59 59 337 -43 121 15 55 121 58 21 119 21 55 123 53 55 0.32
Uncertainty in time = +/- 15 secs
Prediction of 2019 Jul 21.0
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]