Discovery[1] | |
---|---|
Discovered by | Scott S. Sheppard |
Discovery site | Las Campanas Obs. |
Discovery date | 14 August 2021 |
Orbital characteristics[1][2] | |
Epoch 25 February 2023 (JD 2460000.5) | |
Observation arc | 1.17 yr (427 d) |
0.1533891 AU (22,946,680 km) | |
Eccentricity | 0.1585459 |
–1.94 yr (–710.13 days) | |
102.76481° | |
0° 30m 25.027s / day | |
Inclination | 164.54657° (to ecliptic) |
218.88401° | |
217.30730° | |
Satellite of | Jupiter |
Group | Carme group |
Physical characteristics | |
Mean diameter | ≈1 km[3] |
24.0[3] | |
17.4[1] | |
S/2021 J 4 is a small outer natural satellite of Jupiter discovered by Scott S. Sheppard on 14 August 2021, 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.[1]
S/2021 J 4 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 and 0.3, and inclinations between 163 and 166°.[3] It has a diameter of about 1 km (0.62 mi) for an absolute magnitude of 17.4, making it one of Jupiter's smallest known moons.[3]
References
- 1 2 3 4 "MPEC 2023-B40 : S/2021 J 4". Minor Planet Electronic Circulars. Minor Planet Center. 19 January 2023. Retrieved 20 January 2023.
- ↑ "Planetary Satellite Discovery Circumstances". JPL Solar System Dynamics. NASA. Retrieved 10 January 2023.
- 1 2 3 4 Sheppard, Scott S. "Moons of Jupiter". Earth & Planets Laboratory. Carnegie Institution for Science. Retrieved 10 January 2023.