Space · Moons

S/2021 N 1

A moon of Neptune — Neptune's most recently-discovered moon — extreme retrograde orbit.

Quick facts

Parent planet

Neptune

Diameter (mean)

14 km

Mass

1.5 × 10¹⁵ kg
2e-08 Moon masses

Mean orbital radius

50,300,000 km

Orbital period

9750 Earth days

Discovery year

2021

Discoverer

Scott S. Sheppard et al. (announced 2024)

Naming origin

Provisional designation — formal name pending

Surface conditions

S/2021 N 1 is a small, faint retrograde outer moon of Neptune in an extreme orbit. Confirmed and announced in 2024 alongside S/2002 N 5.

Missions and observations

Every Neptune-system mission has had an opportunity to image or characterize S/2021 N 1. The list below is the Neptune-system mission catalog; specific S/2021 N 1 encounters are documented in mission archives.

Mission Year at Neptune Status

Voyager 2

NASA

1989 Completed

Naming etymology

Provisional designation pending a formal Greek sea-figure name from the IAU.

Methodology & sources

Diameter, mass, and orbital parameters from JPL Solar System Dynamics — Physical Parameters. Discovery year and discoverer from the JPL Satellite Discovery Circumstances. Naming etymology from the IAU Working Group for Planetary System Nomenclature. Stylized SVG hero composed from NASA / JPL imagery as visual reference; no photographs are reproduced.

Last refreshed 2026-05-27 by Titan — new page.