Helene

Helene

Moon· orbits Saturn

Helene is a moon orbiting Saturn.

Open in 3D viewSee Helene in the live, interactive 3D map

Key facts

Mass
7.19 × 10¹⁵ kg
0.000000098 Moon masses
Radius
18 km
1% of our Moon's radius
Surface gravity
0.00148 m/s²
0% of Earth's gravity
Orbit around Saturn
2.74 Earth days

Science

Physical

Mass
7.19 × 10¹⁵ kg · 0.000000098 Moon masses
JPL SSD Planetary Satellite Physical Parameters (GM SAT441) — dynamical (spacecraft ephemeris fit)
Radius
18 km · 1% of our Moon's radius
JPL SSD Planetary Satellite Physical Parameters (mean radius)
Density
294 kg/m³ · 0.29× water
Computed from mass and radius
Surface gravity
0.00148 m/s² · 0% of Earth's gravity
Computed from mass and radius
Escape velocity
7.3 m/s · 0% of Earth's escape velocity
Computed from mass and radius

Orbit around Saturn

Distance from Saturn
377,600 km
From JPL orbital elements
Orbital period
2.7 days
From JPL orbital elements
Eccentricity
0.007
From JPL orbital elements
Inclination to Saturn's Laplace plane
0.20 °
From JPL orbital elements · The Laplace plane is the one a moon's orbit precesses about: close in it is the planet's equatorial plane, the plane of the rings, and further out it tilts toward the planet's own orbit.

Radiation & temperature

Insolation
0.0112 S⊕ · 1% of the sunlight Earth receives
Computed from the distance to the Sun (inverse-square; Earth's sunlight = 1), before any atmosphere.

Discovery & history

By
P. Laques and J. Lecacheux

Helene was discovered in 1980 by P. Laques and J. Lecacheux. Saturn's moons are named after the Titans, giants and monsters of Greek and Roman myth. Beyond its discovery and naming, little more about it has been individually recorded.

Images

Images from open archives · credit shown per image