Tau Ceti
Tau Ceti
Fact
Tau Ceti is a Sun-like (G type) star about 11.9 light years from here; it's the closest single such star to us (the Alpha Centauri system is closer and has a sun-like star, but is a multiple). As such it's been a popular place in science fiction, authors from Asimov to Zsoldos have set novels or parts of novels there.
It's a much older star than its near neighbor, Epsilon Eridani (about 5.5 ly away from τ Ceti), and unlike that star we don't yet know if it has planets, but we do know that it has a dust/asteroid disk, bigger than ours but smaller than ε Eridani's. This probably means that any planets in the system get bombarded more frequently by meteors or comets, although that may also depend on the presence and position of large planets which may help shepherd the debris into more confined belts. The star itself is a bit smaller, cooler and dimmer than our own Sun, which moves the habitable zone in closer, but it is still quite a bit brighter and warmer than K-type stars like ε Eridani or α Centauri B.
Planets
Note: Earlier reports suggested five planets, b through f. More recently (August, 2017) this has been refined to just four, with b, c and d being superceded by g and h. Tau Ceti is also believed to have approximately 10x the mass of asteroids and dust as our own solar system.
| Name | Mass M⊕ | Orbit AU | Period (x24h) |
|---|---|---|---|
| I (g) | ≥1.7 ± 0.3 | 0.133 ± 0.002 | 20.00 ± 0.01 |
| II (h) | ≥1.9 ± 0.4 | 0.243 ± 0.003 | 49.41 ± 0.09 |
| Inner H.Z. Edge? | ~0.55 | ~165 | |
| III(e) (binary) | ≥3.99 ± 0.7 | 0.538 ± 0.006 | 162.7 ± 0.5 |
| III-1 (e-1) (Skead) | 3.1 | as above | |
| III-2 (e-2) supermoon | 0.3 | as above | |
| IV (f) | ~3.77 ± 1.21 | ~1.37 ± 0.08 | 616 ± 31 |
| Outer H.Z. Edge? | 1.26 to 1.32 | ~600 | |
| Others TBD | |||
| Dust disk | 6.2 ( >4.6, <9.8) to ≥36 AU |
(Note: For fiction, III is assumed to be binary (or with a very large moon) with a total mass of ~3.4 M⊕)
Fiction
So far in T-Space I haven't written much about Tau Ceti. In The Chara Talisman (aka The Venaticorum Archive), a world circling it is the location of Port Skead, the main spaceport in the system and home base for Jackie Roberts and her ship Sophie. It's a bit over 13.5 light years from α Centauri, so it takes about ten days in warp to get there from Sawyers World or Kakuloa. Once there, it's only a four day trip to ε Eridani.