UPSA Object Registry

Registry · solar system

Prospero

Natural satellite JPL Horizons

Also known as

2 identifiers

Horizons 718S1999_U3 UXVIII 1999U3

Recorded parameters

7 quantities with a single published value

Parameter	Value	Unit	Uncertainty	As published	Source	Reference
Arg of periapse w	180.4	w		Arg of periapse, w	JPL Horizons	JPL Horizons on-line ephemeris system
Eccentricity e	0.441	e		Eccentricity, e	JPL Horizons	JPL Horizons on-line ephemeris system
Inclination i	149.4	i		Inclination, i	JPL Horizons	JPL Horizons on-line ephemeris system
Mean anomaly m deg	197.6	deg		Mean anomaly, M (deg)	JPL Horizons	JPL Horizons on-line ephemeris system
Radius km	< 50 km	km		Radius (km)	JPL Horizons	JPL Horizons on-line ephemeris system
Semi major axis a km	1.62210e+07	km		Semi-major axis, a (km)	JPL Horizons	JPL Horizons on-line ephemeris system
Sid orbital period	1,979.407	d		Sid. orbital period	JPL Horizons	JPL Horizons on-line ephemeris system

Provenance

where this card came from

Archive	Read at (UTC)	Record
JPL Horizons	2026-08-14 17:11	open at source

Machine-readable: /api/v1/object/prospero · Registry entry updated 2026-08-14.