| Minorplanet: | yes |
| Background: |
|
| 106 Dione | |
| Discovered: | 10 October 1868 |
| Mpc Name: | (106) Dione |
| Alt Names: | A868 TA, 1902 TA |
| Pronounced: | [1] |
| Epoch: | 31 July 2016 (JD 2457600.5) |
| Semimajor: | 3.17451AU |
| Perihelion: | 2.64584AU |
| Aphelion: | 3.7032abbr=onNaNabbr=on |
| Eccentricity: | 0.16653 |
| Period: | 5.66 yr (2065.9 d) |
| Inclination: | 4.5972° |
| Asc Node: | 62.163° |
| Arg Peri: | 329.725° |
| Avg Speed: | 16.61 km/s |
| Dimensions: | |
| Surface Grav: | 0.0410 m/s² |
| Escape Velocity: | 0.0775 km/s |
| Rotation: | 16.26abbr=onNaNabbr=on 16.26 ± 0.02 h |
| Spectral Type: | G (Tholen) Cgh (Bus) |
| Abs Magnitude: | 7.41 |
| Mean Motion: | / day |
| Observation Arc: | 145.03 yr (52972 d) |
| Uncertainty: | 0 |
| Moid: | 1.65175AU |
| Jupiter Moid: | 1.73379AU |
| Tisserand: | 3.175 |
106 Dione is a large main-belt asteroid. It probably has a composition similar to 1 Ceres. It was discovered by J. C. Watson on October 10, 1868, and named after Dione, a Titaness in Greek mythology who was sometimes said to have been the mother of Aphrodite, the Greek goddess of love and beauty. It is listed as a member of the Hecuba group of asteroids that orbit near the 2:1 mean-motion resonance with Jupiter. The orbital period for this object is 5.66 years and it has an eccentricity of 0.17.
Measurements made with the IRAS observatory give a diameter of and a geometric albedo of . By comparison, the MIPS photometer on the Spitzer Space Telescope gives a diameter of and a geometric albedo of . Dione was observed to occult a dim star on January 19, 1983, by observers in Denmark, Germany and the Netherlands. A diameter of was deduced, closely matching the value acquired by the IRAS satellite. As of 2012, the mean diameter derived through occultation measurements is .
Photometric observations of this asteroid collected during 2004–2005 show a rotation period of hours with a brightness variation of magnitude. It is classified as a rare G-type asteroid, suggesting it has a carbonaceous composition with phyllosilicate minerals also being detected.