| Minorplanet: | yes |
| Background: |
|
| 134 Sophrosyne | |
| Discoverer: | Karl Theodor Robert Luther |
| Discovered: | 27 September 1873 |
| Mpc Name: | (134) Sophrosyne |
| Pronounced: | [1] |
| Mp Category: | Main belt |
| Epoch: | 31 July 2016 (JD 2457600.5) |
| Semimajor: | 2.56295AU |
| Perihelion: | 2.26311AU |
| Aphelion: | 2.8628abbr=onNaNabbr=on |
| Eccentricity: | 0.11699 |
| Period: | 4.10 yr (1498.7 d) |
| Inclination: | 11.6018° |
| Asc Node: | 345.986° |
| Arg Peri: | 84.7156° |
| Mean Anomaly: | 229.885° |
| Avg Speed: | 18.54 km/s |
| Mean Diameter: | 108 112.188 km |
| Mass: | (1.267 ± 0.575/0.398) kg |
| Density: | 1.713 ± 0.778/0.538 g/cm3 |
| Surface Grav: | m/s |
| Escape Velocity: | km/s |
| Rotation: | 17.19abbr=onNaNabbr=on |
| Spectral Type: | C (Tholen) |
| Abs Magnitude: | 9.04, 8.770 |
| Albedo: | 0.0436 ± 0.0122 |
| Single Temperature: | ~174 K |
| Mean Motion: | / day |
| Observation Arc: | 138.60 yr (50625 d) |
| Uncertainty: | 0 |
| Moid: | 1.31034AU |
| Jupiter Moid: | 2.42537AU |
| Tisserand: | 3.396 |
| Named After: | sophrosyne |
134 Sophrosyne is a large main-belt asteroid that was discovered by German astronomer Robert Luther on 27 September 1873, and was named after the concept of sophrosyne, Plato's term for 'moderation'. Classified as a C-type asteroid, it has an exceedingly dark surface and most probably a primitive carbonaceous composition.
An occultation of a star by 134 Sophrosyne was observed 24 November 1980, in the United States. Timing information from this event allowed a diameter estimate of 110 km to be derived. Photometric observations of the asteroid in 2015 produced a lightcurve indicating a rotation period of with a variation amplitude of in magnitude. This provided a good match to the only previous determination in 1989.