Astro Corner
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Celestial object
257 Silesia (A886 GB)
257, 257 Silesia (A886 GB), Silesia
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Reference data
RADate-dependentMoving object · use an ephemeris
DecDate-dependentMoving object · use an ephemeris
Magnitude—
Angular size—
Position angle—
Distance—
Constellation—
Solar System catalogue
JPL SBDBMoving-object reference
Comets and minor planets move against the background sky. Astro Corner therefore keeps their orbital catalogue record separately and does not pretend a single RA/Dec is permanently correct.
Primary designation257
JPL SPK-ID20000257
Orbit classMBA
Orbit IDJPL 81
Near-Earth objectNo
Potentially hazardousNo
Epoch · JD2461200.5
Eccentricity0.112296611492
Semi-major axis3.118550155 AU
Perihelion distance2.768347540 AU
Orbital period2,011.5 days
Earth MOID1.781930000 AU
Jupiter Tisserand3.204000
Inclination3.61229854°
Absolute magnitude · H9.6800
Diameter72.660000 km
Albedo0.054500
Last catalogue sync2026-09-12 01:00:06
Planning coordinates are intentionally separate.A later Horizons ephemeris layer can calculate the object's apparent position for a specific date, time and observing location. Until then, static-sky tools are hidden for this record rather than showing misleading coordinates.
Open JPL Small-Body Database 
Reference transparencySources & data provenanceSee where catalogue identities and imported reference fields came from.4 records
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Images of this object
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