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Updated: 2020 Jan 12, 19:32 UT
Event Rank : 36
(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 2020 Feb 26 UT, the 13.8 km diameter asteroid (4820) Fay will occult a 8.6 mag star in the constellation Auriga for observers along a significantly uncertain path across southern Queensland, north-eastern New South Wales.
In the case of an occultation, the combined light of the asteroid and the star will drop by 6.83 mag to 15.43 mag (the magnitude of the asteroid) for at most just 1.0 seconds.
This update is based on UNSO/Flagstaff astrometry for the asteroid kindly provided by Hugh Harris, 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 HIP 27860 by 4820 Fay on 2020 Feb 26
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
155 25 6 -33 0 0 9 26 54.1 23 356 -15 155 17 27 155 32 44 154 40 19 156 9 26 1.05
154 41 21 -32 0 0 9 26 48.2 24 357 -14 154 33 43 154 48 59 153 56 38 155 25 38 1.05
153 56 35 -31 0 0 9 26 42.1 25 358 -14 153 48 57 154 4 12 153 11 52 154 40 50 1.05
153 10 44 -30 0 0 9 26 35.6 26 358 -14 153 3 6 153 18 21 152 25 59 153 55 0 1.05
152 23 45 -29 0 0 9 26 28.9 27 359 -13 152 16 5 152 31 23 151 38 55 153 8 5 1.06
151 35 33 -28 0 0 9 26 21.8 28 360 -13 151 27 53 151 43 13 150 50 36 152 20 0 1.06
150 46 6 -27 0 0 9 26 14.4 29 1 -13 150 38 24 150 53 47 150 0 57 151 30 42 1.06
149 55 18 -26 0 0 9 26 6.6 30 2 -12 149 47 34 150 3 2 149 9 55 150 40 7 1.06
149 3 4 -25 0 0 9 25 58.5 31 2 -12 148 55 17 149 10 51 148 17 24 149 48 10 1.06
148 9 19 -24 0 0 9 25 50.1 32 3 -11 148 1 28 148 17 9 147 23 17 148 54 45 1.07
147 13 57 -23 0 0 9 25 41.2 33 4 -10 147 6 1 147 21 51 146 27 28 147 59 46 1.07
146 16 49 -22 0 0 9 25 32.0 34 5 -10 146 8 48 146 24 48 145 29 50 147 3 6 1.07
145 17 48 -21 0 0 9 25 22.5 35 7 -9 145 9 42 145 25 53 144 30 14 146 4 38 1.07
144 16 44 -20 0 0 9 25 12.4 36 8 -8 144 8 31 144 24 56 143 28 29 145 4 13 1.08
143 13 28 -19 0 0 9 25 2.0 37 9 -8 143 5 7 143 21 48 142 24 25 144 1 41 1.08
142 7 47 -18 0 0 9 24 51.1 38 10 -7 141 59 16 142 16 15 141 17 48 142 56 50 1.08
140 59 26 -17 0 0 9 24 39.8 38 12 -6 140 50 45 141 8 5 140 8 24 141 49 28 1.08
139 48 8 -16 0 0 9 24 27.9 39 13 -5 139 39 16 139 57 0 138 55 53 140 39 19 1.09
Uncertainty in time = +/- 3 secs
Prediction of 2020 Jan 12.0
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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