Friday, the 20 of December, 2019 ~ 18:49:22 UTC (87) Sylvia occult TYC 1940-00875-1 (mag 11.26)


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  • Legend for each body
    • green line is the central line
    • blue lines show the estimate size
    • red lines the 1-sigma error for the path
Event
  • Date : Friday, the 20 of December, 2019 ~ 18:49:22 UTC
  • Max duration : 24.1 seconds
  • Shadow velocity : 11.9 km/s
  • Barycenter prediction : NIMAv32019Nov15
Asteroidal system
  • Name : (87) Sylvia
  • Mag : 12.64
  • Geocentric distance : 2.8448 AU
  • Number of Components : 3
  • Component : Sylvia
  • Diameter : 286.0 km
  • Max duration : 24.1 sec
  • Component : Romulus
  • Diameter : 16.0 km
  • Max duration : 1.3 sec
  • Component : Remus
  • Diameter : 10.0 km
  • Max duration : 0.8 sec
Occulted Star
  • Name : TYC 1940-00875-1
  • Used RA   :   08h21m51s9 J2000
  • Used DEC : +28d48m58s9 J2000
  • Mb : 12.11
  • Mv : 11.26
  • Mr : 10.80
  • VizieR - Aladin
Historic
  • 2019-11-28 : Create prediction
Prediction for (87) Sylvia system. (wide views)

Sylvia

Sylvia

Sylvia

Sylvia

Romulus

Romulus

Romulus

Romulus

Remus

Remus

Remus

Remus
Ephemerides from IMCCE

Ephemeris for Sylvia

Ephemeris for Romulus

Ephemeris for Remus

Ephemeris from Miriade for the date of occultation and geocenter frame. For more specific ephemeris please use the documentation of Miriade.

Orbitography for the (87) Sylvia system

Romulus

Romulus

Astrometric observations of Romulus centered on (87) Sylvia.
Dot represents one observed position. The vector shows ephemeris position from observed position.

Remus

Remus

Astrometric observations of Remus centered on (87) Sylvia.
Dot represents one observed position. The vector shows ephemeris position from observed position.

All components on the tangent plane

Remus
Propagation of the solutions
We use all orbits from 1,2 and 3 sigma issued from Genetical algorithm, and we see where the satellite is for the occultation date. North on top, and East on right.
  • Center at coordinates 0,0 is Primary
  • Black dots show the orbit with the best solution at the date of occultation
  • Green zone show orbits covering 1-sigma error
  • Blue zone for 2-sigma
  • Red zone for 3-sigma

Romulus

Romulus
This figure represent 991279 orbits computed to the occultation date. Each orbit is classify throw its performance, given an accuracy in kilometer :
  • 1-σ error = 96 km
  • 2-σ error = 99 km
  • 3-σ error = 107 km

Remus

Remus
This figure represent 991279 orbits computed to the occultation date. Each orbit is classify throw its performance, given an accuracy in kilometer :
  • 1-σ error = 67 km
  • 2-σ error = 71 km
  • 3-σ error = 76 km
Contents
  • Orbital solution fitted by Genoid project (Vachier F., Berthier J., Carry B.) IMCCE/CNRS
  • Ephemeris has made available with Miriade Project (Berthier J. & Vachier F.) IMCCE/CNRS
  • Occultation Prediction by Vachier F. using Occult (Occultation Prediction Software by D.Herald)
  • Ephemeris and offset for the barycenter are based on NIMA