| Therne | |
|---|---|
| M3V | |
| Stellar properties | |
| Spectral type | M3V |
| Luminosity (visual) | 0.0013 L☉ (V-band) |
| Age | ~4.6 billion years |
| Color | Deep orange-red |
| Orbit | |
| Semi-major axis | 4.488e+9 km |
| Eccentricity | 0.3 |
| Periastron | 21.000 AU |
| Apastron | 39.000 AU |
| Observation | |
| Apparent mag. (bright) | −13.3 (periastron opposition) |
| Apparent mag. (dim) | −11.9 (apastron conjunction) |
| Angular diameter (max) | 35.6 arcsec (periastron) |
| Angular diameter (min) | 19.2 arcsec (apastron) |
| System | |
| Companion of | Sun |
| Companion | The Sun (G2V) |
| Planets | 1 |
Therne, historically known as the Follower, is the second star of the Sunly system and the binary companion to the Sun. It is a red dwarf of spectral classification M3V, orbiting the Sun at a mean distance of 30 AU with a period of 140.9 years. Therne is the brightest object in Sunly's night sky apart from the Sun itself, varying between roughly 0.5 and 1.7 times the brightness of a full moon depending on its orbital phase.