Zeta (1) Reticuli
| Zeta (1) Reticuli | |
| Stellar characteristics | |
|---|---|
| Constellation | Reticulum |
| Right ascension (Epoch J2000) | 03h 17m 46.20s |
| Declination (Epoch J2000) | -62° 34' 31.20" |
| Spectral type | G2.5-5 V |
| Distance from Sol | 39.5 ly |
| Other designations | Valinor, Zet1 Ret, HR 1006, Gl 136, Hip 15330, HD 20766, CP(D)-63 217, SAO 248770, LHS 171, LTT 1573, LFT 275, and LPM 146. |
Zeta (1) Reticuli is part of a wide-binary system, along with Zeta (2) Reticuli, and is located around 39.4 to 39.5 light-years from Sol. It lies in the west central part of the constellation Reticulum, the Reticule or Net (an old astronomical instrument used to measure star positions).
Zeta (1) Reticuli is a yellow-orange main sequence dwarf star of spectral and luminosity type G2.5-5 V, with about 93 percent of Sol's mass, around 91 percent of its diameter, and 79 percent of its luminosity. The star may be 60 percent as enriched as Sol with elements heavier than hydrogen ("metallicity"), based on its abundance of iron[1]. Zeta (1) has a brighter but distant stellar companion , Zeta (2) Reticuli, currently located around 3,750 AUs away[2], with common proper motion and equal radial velocities[3]. The evidence has grown against either star having a close stellar companion[3][4].
Once thought to be old Population II, galactic-halo-type subdwarf stars, Zeta (1) and its companion are more likely to be old disk stars[3], that may be as much as eight billion years old. An earlier hypothesis that the stars were relatively dim because of a high abundance of helium[3]has been refuted recently[1]. The pair is now thought to be part of the Zeta Herculis stellar moving (kinematic) group of high velocity stars as defined by Olin J. Eggen in 1958, which no longer includes Zeta Herculis itself[1].
Around Zeta (1), the orbit of an Earth-like planet would be close in, around 0.9 AU -- between the orbital distances of Venus and Earth in the Solar System -- with an orbital period of around 320 days.
(Data from SolStation.com)
The system is known to the Fen as Valinor[5], though as of 2013 it has not yet been visited.
Notes
- ↑ 1.0 1.1 1.2 (del Peloso et al, 2000)
- ↑ (based on an observed separation of 310" and HIPPARCOS distance estimates of 39.40 to 39.53 ly)
- ↑ 3.0 3.1 3.2 3.3 (Da Silva and Foy, 1987)
- ↑ (Bonneau et al, 1980, pp. 187-188)
- ↑ We suspect the VVS is responsible in some way
