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Jupiter Occults UCAC4 341-085052 on 18th of January 2019
On the 18th of January 2019 between approx. 4h30 and 5h UTC Jupiter will occult UCAC4 341-085052. The star is the variable star SY Oph. The brightness varies between 9m7 and 11m4 as given by Payne-Gaposchkin, C. (1954AnHar.113..189P) and also in the database of the AAVSO. The spectral type is M7, which is extremely red.
The star would not be interesting with these faint magnitudes, however, the Gaia DR2 catalog shows it with a G mag of 6.1898 and with a BP of 9.166 for wavelengths of 400-500nm and RD = 4.7629 for wavelengths of 600-750nm. Further more, the 2MASS magnitudes are:
J=1.88 H=0.88 K=0.53
In other catalogues, the following magnitudes are given:
UCAC4 J 1.88
K 0.525
B 10.583
V 9.096
R 8.651
Hipparcos V = 8.02
PANSTARRS imag 5.556
rmag 7.519
Therefore it looks like an interesting occultation, specially if methane band filters are used (890nm).
In order to get some ideas, how bright the star is, an images were taken last October from the International Amateur Observatory (IAS) in Hakos, Namibia by IOTA/ES member Karl-Ludwig Bath. However, only images without filters with a ASI120mm camera, a black and white CMOS camera and a 50cm telescope. There are two other 9mag stars close by, UCAC4 341-084944 (Gmag 7.945) and UCAC4 340-085356 (Gmag 9.122). The ASI120mm camera has a sensitivity range up to 1000nm, but only with relatively small quantum efficiency beyond 800nm. The SY Oph star shows an approx. fourfold intensity compared to these stars, confirming the brightness of SY Oph.
Using Methane band filters and/or J or K band facilities, it could be an interesting occultation.
The star position (J2000, Gaia DR2) is
RA: 16 55 06.7558
Dec:-21 58 10.1774
More infos will follow soon!
Areas of Visibility
The main area of visibility is the eastern mediterranean area, including Greece, Cyprus and Crete. The following map generated by OCCULT shows the situation:
Enlarging the map leads to the following image:
East of the yellow line, the sun is above the horizon. Good visibility will be in large parts of Egypt, Crete, Greece mainland and parts of Italy.
Local circumstances for observing sites around Europe
As examples, local circumstances are given here for Iraklion, Athens and Sofia. Timings are in UTC
Time of Alt. Sun alt Ingres Egres
central occ. UTC UTC
Iraklion: 4 42 47 21 -9 4 28.4 4 57.1
Athens 4 42 48 18 -11 4 28.6 4 56.9
Sofia 4 42 53 14 -13 4 29.1 4 56.6
For many other stations you find the information of time of central occultation
here and for the time of ingres and egres
here.
More infos will follow.
If you have questions, don't hesitate to write to
info@iota-es.de
