Saturn's Inuit group of satellites
The Inuit group is a dynamical grouping of the prograde irregular satellites of Saturn which follow similar orbits. Their semi-major axes range between 11 and 18 Gm, their inclinations between 40° and 50°, and their eccentricities between 0.15 and 0.48. They take about 2 years to orbit Saturn.
The International Astronomical Union uses names taken from Inuit mythology for these moons.
The group appeared quite homogeneous in early observations, the satellites displaying light-red colour and similar infrared spectra. Recent observations, however, revealed that Ijiraq is distinctly redder than Paaliaq, Siarnaq and Kiviuq. In addition, unlike the other three, Ijiraq's spectrum does not display weak absorption near 0.7 μm. This feature is attributed to a possible water hydration.
The spectral homogeneity is consistent with a common origin in the break-up of a single object but the dispersion of the orbital parameters requires further explanation. Recently reported secular resonances among the members could provide the explanation of the post-collisional dispersion.
The discovery of two new moons in this group was announced in October 2019. A team led by Scott S. Sheppard using the Subaru Telescope at Mauna Kea discovered 20 new moons, each about in diameter. A public naming contest for these moons will be restricted to names from Inuit mythology.Names
The members of the group discovered before 2019 are :
- Kiviuq
- Ijiraq
- Paaliaq
- Siarnaq
- Tarqeq