Dione
Dione
Moon
Pisces
Visible
Level 6
Professional/Research - Timing dependent
Properties
Magnitude
10.4
Angular Size
0.2 arcmin
Type: Moon
Distance: 0.003 AU
Orbital Period: 2.7 days
Diameter: 1,123 km
Atmosphere: Thin oxygen
Features: Wispy terrain, craters, ice cliffs
Icy moon with bright wispy terrain on trailing hemisphere. Part of Saturn's 'major four'. Requires 4-6 inch telescope.
Position & Identifiers
RA
00h 21m 06.9s
Dec
-00° 02' 17.5"
Constellation
Pisces
Catalog
Dione
Physical Properties
Diameter
1,123 km
(0.09× Earth)
Mass
1.10e21 kg
Albedo
0.70
(70% reflected)
Temperature
-220°C to -186°C
Rotation
2.7 days
Atmosphere
Thin oxygen
Surface
Wispy terrain, craters, ice cliffs
Angular Size
0.1″ (current)
Orbital Properties
Semi-major Axis
0.0025 AU
(377,435 km)
Eccentricity
0.0022
Inclination
0.02°
Orbital Period
2.7 days
Distance
10.517 AU
(1.46 light-hours)
Elongation
2.3°
Near Sun
Observing Tips
Best Months
April
, May
, June
Visibility
Telescope
Where to Look
Near Saturn
Notes
Icy moon with bright wispy terrain on trailing hemisphere. Part of Saturn's 'major four'. Requires 4-6 inch telescope.
Parent Body
Discovery
Discovered by
Giovanni Cassini
Date
1684-03-21
Current Ephemeris
10.517
AU from Earth
1.57B
km
0.1″
Angular Size
2°
Elongation
Visibility
Set a location in User Settings to see visibility data.
Community Photos (1)
Credit: NASA. License: Public domain. (Wikimedia Commons)
Skybred Feb 28, 2026