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Occultation by (87) Sylvia and its Satellites Romulus and Remus, 2019 Oct 29

This is one of the occultation highlights of the year.

The triple asteroid system (87) Sylvia will occult a 10.1 mag star around 23:38 UT on October 29. The European continent is located inside the path.

The predictions below are based on calculations by Steve Preston, IOTA, on 2019 Oct 15. http://asteroidoccultation.com/2019_10/1029_87_61910.htm

Calculations by Frédéric Vachier et al. (IMCCE) show the paths about 20 km shifted to the East compared to S. Preston’s prediction.
http://fredvachier.free.fr/binaries/occult/2019/2019-10-29T23_43_28.200_87_NIMA2019Oct09_Binary_solution_1_Kepler/

The Target Star

TYC 1932-00469-1 on 2019 Oct 29, 23:36 UT
RA: 08 21 01.7490 DE: +25 57 43.125
(Astrometric position with proper motion and parallax to date of event) Star V mag 10.1

The Path of (87) Sylvia

The path of (87) Sylvia will cross Portugal, Spain, France, Switzerland, Austria, Germany, Luxembourg, Poland, the Baltic countries, Russia and Finland.

Approximate projected path width: 440 km
Expected maximum duration: 23.0 s
Drop of magnitude: 3.3 mag

Details, times and path coordinates of Steve Preston’s prediction of Oct 15:
http://asteroidoccultation.com/2019_10/1029_87_61910.htm

A path map of (87) Sylvia with zoom function is available on Derek C. Breit’s web page:
http://www.poyntsource.com/New/Global.htm

The Path of Romulus

The shadow of Romulus is predicted to be inside the western part of the shadow path of (87) Sylvia.
Maximum duration of occultation: 1.3 s
Predicted times and path coordinates of Romulus

The Path of Remus

The shadow of Remus is predicted to follow the eastern path limit of the shadow of (87) Sylvia.
Maximum duration of occultation: 0.8 s

Predicted times and path coordinates of Remus

THE OCCULTATIONS OF THE SATELLITES ARE EXPECTED TO BE EARLIER THAN THE OCCULTATION BY (87) SYLVIA. ALL OBSERVERS SHOULD START THIER RECORDINGS AT LEAST 2 MINUTES BEFORE THE EXPECTED OCCULTATION TIME OF THE MAIN BODY.
PLEASE CHECK PREDICTED TIMES FOR YOUR LOCATION.

Animated path map of Sylvia, Romulus and Remus based on Steve Preston’s prediction of 2019 Oct 15:

PATH_EUROPE_ as an animated gif



About the animated path map:
The occultations will occur between the dashed 1-sigma lines with a probability of 68 %. (Map data: Steve Preston, IOTA, map animation: Occult V4, O. Klös, IOTA/ES)

Good luck with your observation!

Please send your observation reports to: pr@iota-es.de


Oliver Klös
IOTA/ES, Public Relations