S/2021 J 1
S/2021 J 1 is a small outer natural satellite of Jupiter discovered by Scott S. Sheppard on 12 August 2021, using the 6.5-meter Magellan-Baade Telescope at Las Campanas Observatory, Chile. It was announced by the Minor Planet Center on 5 January 2023, after observations were collected over a long enough time span to confirm the satellite's orbit. S/2021 J 1 is part of the Ananke group, a cluster of retrograde irregular moons of Jupiter that follow similar orbits to Ananke at semi-major axes between , orbital eccentricities between 0.1–0.4, and inclinations between 139–155°. It has a diameter of about  for an absolute magnitude of 17.3, making it one of Jupiter's smallest known moons. References 

Ananke group
Moons of Jupiter
Irregular satellites
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Discoveries by Scott S. Sheppard
Moons with a retrograde orbit