Vital Statistics for Jupiter’s Rings and Inner Satellites

Rings of Jupiter

Feature Inner Boundary (km) Outer Boundary (km) Optical Depth Thickness (km) Notes
Halo 89,400 123,000 3 x 10^-6 ~ 10,000 Densest in a central core < 1000 km thick.
Main Ring 123,000 128,940 5 x 10^-6 ≤ 100 Metis and Adrastea orbit near its outer edge.
Amalthea Ring [1] 128,940 181,350 ~ 10^-7 2600 Inner component of the Gossamer Ring, bounded by the orbit of Amalthea.
Thebe Ring [1] 128,940 221,900 ~ 10^-7 8800 Outer component of the Gossamer Ring, bounded by the orbit of Thebe.
Thebe Extension [1] 221,900 280,000 ~ 10^-8 8800 A very faint outward extension to the Thebe Ring.

Inner Satellites of Jupiter

Name Semimajor Axis (km) Period (days) Eccentricity Inclination (deg) Mean Radius (km) Mass (10^20 kg)
Metis 127,979 0.294780 < 0.004 ~ 0 20  
Adrastea 128,980 0.29826 ~ 0 ~ 0 10  
Amalthea 181,300 0.498179 0.003 0.40 86  
Thebe 221,900 0.6745 0.015 0.8 50  
Io 421,600 1.769138 0.0041 0.040 1,821 893.3
Europa 670,900 3.551810 0.0101 0.470 1,565 479.7
Ganymede 1,070,000 7.154553 0.0015 0.195 2,634 1482
Callisto 1,883,000 16.689018 0.007 0.281 2,403 1076

Except where noted, from Murray, C. D., and S. F. Dermott 1999. Solar System Dynamics, Cambridge University Press.

[1] Burns, J. A., M. R. Showalter, D. P. Hamilton, P. D. Nicholson, I. de Pater, M. E. Ocker-Bell, and P. C. Thomas 1999. The formation of Jupiter’s faint rings. Science 284, 1146-1150.