Helene was discovered by P. Laques and J. Lecacheus in 1980 through ground based observations. Helene is called a Dione Trojan satellite because it shares the same orbit as Dione at about 60 degrees ahead of its larger companion. Its diameter is about 36 x 32 x 30 kilometers (22 x 20 x 19 miles).
Discovered by P. Laques & J. Lecacheus
Date of discovery 1980
Mass (kg) ?
Radius (km) 18x16x15
Radius (Earth = 1) 2.8222e-03
Mean density (gm/cm^3) ?
Mean distance from Saturn (km) 377,400
Rotational period (days) ?
Orbital period (days) 2.7369
Mean orbital velocity (km/sec) 10.03
Orbital eccentricity 0.005
Orbital inclination (degrees) 0.2
Visual geometric albedo 0.7
Magnitude (Vo) 18.5
|Views of Helene|
This image of Helene was acquired by the Voyager 2 spacecraft on August 25, 1981. (Credit: Calvin J. Hamilton)
Saturn Dione Rhea
Copyright © 1997 by Calvin J. Hamilton. All rights reserved.