S/2018 J 3
              < S 
 
            
          | Discovery | |
|---|---|
| Discovered by | Scott S. Sheppard | 
| Discovery site | Las Campanas Obs. | 
| Discovery date | 12 May 2018 | 
| Orbital characteristics | |
| Epoch 25 February 2023 (JD 2460000.5) | |
| Observation arc | 4.35 yr (1590 d) | 
| 0.1525861 AU (22,826,560 km) | |
| Eccentricity | 0.2731285 | 
| –1.93 yr (–704.56 days) | |
| 16.59790° | |
| 0° 30m 39.453s / day | |
| Inclination | 164.90043° (to ecliptic) | 
| 240.00514° | |
| 296.52870° | |
| Satellite of | Jupiter | 
| Group | Carme group | 
| Physical characteristics | |
| ≈1 km | |
| 23.9 | |
| 17.3 | |
S/2018 J 3 is a small outer natural satellite of Jupiter discovered by Scott S. Sheppard on 12 May 2018, using the 6.5-meter Magellan-Baade Telescope at Las Campanas Observatory, Chile. It was announced by the Minor Planet Center on 19 January 2023, after observations were collected over a long enough time span to confirm the satellite's orbit.
S/2018 J 3 is part of the Carme group, a tight cluster of retrograde irregular moons of Jupiter that follow similar orbits to Carme at semi-major axes between 22–24 million km (14–15 million mi), orbital eccentricities between 0.2–0.3, and inclinations between 163–166°. It has a diameter of about 1 km (0.62 mi) for an absolute magnitude of 17.3, making it one of Jupiter's smallest known moons.