121725 Aphidas

ASTEROIDCentaur

ILLUSTRATION · NO MEASURED PROPERTIES

[

OVERVIEW

] ASTEROID

121725 Aphidas is a . Its absolute magnitude () is 8.88. It orbits the Sun at a mean distance of 17.96 . It is catalogued as 121725 Aphidas (1999 XX143). It was discovered in 1999.

WHAT IT IS: Centaur
HOW FAR: 17.96
HOW BRIGHT IN ITSELF (H)
ONE ORBIT TAKES: 76.1

[

OBSERVING

] FROM WHERE YOU ARE

What it takes to see 121725 Aphidas for yourself. Everything in this part of the page is worked out for a real horizon, a real night and the equipment you say you have.

WHERE IT IS NOW

[

CATALOG DATA

] 14 FIELDS

The raw catalogue values, as the source published them, with the error bars where one was published — sorted by what each set of figures is about rather than by the order they happened to be stored in.

THE ORBIT

The shape of the path, where the object sits on it, and the instant those figures were true of. An orbit is a fit to observations and drifts away from the real one either side of its epoch.

Orbital period: 76.11 ±0.34
Eccentricity
Inclination: 6.77
Longitude of ascending node: 103.69
Argument of perihelion: 215.92
Mean anomaly: 249.7
Element epoch: 2461200.5000
Perihelion passage: 2469717.9100
Minimum distance from Earth's orbit: 8.66
Orbit class: CEN

WHEN IT WAS FOUND

Who first saw it, from where, and by what method.

Discovered by: Hergenrother, C. W.
Discovered from: Mount Hopkins
Discovered on: 1999-12-13
First observed: 1999-12-13

[

ALSO KNOWN AS

] 3 DESIGNATIONS

Asteroid 121725
Asteroid 121725 Aphidas (1999 XX143)
Common name Aphidas

[

LOOK IT UP ELSEWHERE

] 1 SERVICE

Each link carries the identifier printed beside it. Nothing on this page is a measurement of our own, so a number that disagrees with one of these is worth reporting — and a service that has never catalogued this object under this name will say so plainly.

JPL Small-Body Database121725
The orbit these elements were taken from, with its uncertainty, its close approaches and every observation behind the fit.

[

CITE THIS PAGE

] DR1

This page is live and its numbers move when an upstream refreshes, so the citation names the release the rows belong to rather than the day you read them. The release itself is frozen, republished as a bundle, and is what a data-availability statement should point at.

PLAIN TEXT

SpaceCatalog. 121725 Aphidas [catalogue entry]. Data release DR1 (2026-08-21). https://spacecatalog.org/object/121725-aphidas

BIBTEX

@misc{spacecatalog_121725-aphidas,
  author       = {{SpaceCatalog}},
  title        = {{121725 Aphidas}},
  howpublished = {SpaceCatalog, data release DR1 (2026-08-21)},
  year         = {2026},
  url          = {https://spacecatalog.org/object/121725-aphidas},
  note         = {Catalogue entry, data release DR1 (2026-08-21). Values from JPL Small-Body Database.}
}

The values above were taken from JPL Small-Body Database — Public domain (NASA/JPL). Citing this page does not replace citing that catalogue.

[

RELATED OBJECTS

] 8 LINKED

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