Actaea (moon)

Actaea
Salacia and its moon Actaea, imaged by the Keck telescope on 3 August 2010. Actaea is the fainter object to the left of Salacia.
Discovery
Discovered byKeith S. Noll, Harold F. Levison, Denise C. Stephen, William M. Grundy
Discovery date21 July 2006
Designations
Designation
Salacia I
Pronunciation/ækˈtə/
S/2006 (120347) 1
AdjectivesActaean /ækˈtən/
Orbital characteristics
5724±27 km
Eccentricity0.0098±0.0038
5.493882±0.000023 days
Inclination23.59±0.36°
45.2±1.6°
134±23°
Satellite ofSalacia
Physical characteristics
Dimensions284±10 km
Mass20×1018 kg
Albedo0.035 +0.010/−0.007
Spectral type
V–I = 0.89±0.02 (Actaea)
1.9 mag

    Actaea, formal designation (120347) Salacia I, is a natural satellite of the classical Kuiper belt object 120347 Salacia. Its diameter is estimated to be approximately 300 km (190 mi), which is approximately one-third the diameter of Salacia; thus, Salacia and Actaea are viewed by William Grundy et al. to be a binary system. Assuming that the following size estimates are correct, Actaea is about the sixth-biggest known moon of a trans-Neptunian object, after Charon (1212 km), Dysnomia (700 km), Vanth (443 km), Ilmarë (326 km), and Hiʻiaka (320 km), but possibly also Hiisi (250 km).