Tau Ceti
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cetus |
| Right ascension | 01h 44m 04.1s |
| Declination | -15° 56' 14" |
| Apparent magnitude (V) | 3.49 |
| Characteristics | |
| Spectral type | G8 Vp |
| U−B color index | 0.21 |
| B−V color index | 0.72 |
| Variable type | None |
| Astrometry | |
| Radial velocity (Rv) | -17 km/s |
| Proper motion (μ) | RA: -1721.82 mas/yr Dec.: 854.07 mas/yr |
| Parallax (π) | 274.39 ± 0.76 mas |
| Distance | 11.88 ly (3.644 pc) |
| Absolute magnitude (MV) | 5.68 |
| Details | |
| Mass | 0.81 M☉ |
| Radius | 0.77 R☉ |
| Luminosity | 0.59 L☉ |
| Temperature | 5,380 K |
| Metallicity | 22-74% |
| Rotation | 31 days |
| Age | 1.0 × 1010 years |
| Other designations | |
Tau Ceti (τ Cet / τ Ceti) is a star commonly mentioned by science fiction authors since it is similar to the Sun in mass and spectral type in addition to being relatively close to us. However, Tau Ceti is a "metal-deficient" star and therefore is thought to be less likely to have rocky planets around it. No companions have yet been detected through astrometric or radial velocity measurements.
In 2004 a team of UK astronomers led by Jane Greaves discovered that Tau Ceti has more than ten times the amount of cometary and asteroidal material orbiting it than the Sun does. This was determined by measuring the disc of cold dust orbiting the star produced by collisions between such small bodies. This result puts a damper on the possibility of complex life in this system, as planets there would suffer from large impact events roughly ten times more frequently than Earth. However, it is possible that a large Jupiter-sized gas giant could deflect comets and asteroids. On the bright side, this does tip the scales in favour of the star having planets.
Tau Ceti can be seen with the unaided eye as a faint star in the constellation of Cetus.
In fiction
Several science fiction novels and other media are set on or around a habitable planet orbiting Tau Ceti, of which the following is a sample.
- In Isaac Asimov's Robot and Foundation novels, the planet Aurora and its two asteroidal satellites orbit Tau Ceti.
- In the film version of Barbarella, the decadent city of Sogo is on a planet in the Tau Ceti system.
- In Harry Turtledove's Worldwar series this is the home star of the invading aliens known as the Race.
- In the Marathon game trilogy, Tau Ceti IV is the location of a human colony, about which the colony ship U.E.S.C. Marathon orbits.
- In the game System Shock 2, Tau Ceti V was where the starship Von Braun travelled on its maiden voyage. It was also the source of the invasion on the ship by both the AI SHODAN and the SHODAN-created lifeforms, the Annelids, which evolved into The Many.
- Pete Cooke's 1985 ZX Spectrum computer game Tau Ceti, published by CRL, was set on an airless planet orbiting the star. [1]
- In Larry Niven's Known Space series, the human colony of Plateau orbited Tau Ceti.
- In Dan Simmon's Hyperion Cantos, Tau Ceti is orbited by Tau Ceti Center, capitol of the Hegemony of Man.
- In The Powers of Matthew Starr, the planet Quadris is identified as being a planet of Tau Ceti.
- In Brian Antoine's online serial novella Tales of the Family nas Kan, a sci-fi/magic-based furry society inhabits a planet in the Tau Ceti system.
- In Ursula K. Le Guin's The Dispossessed, the action takes place in a fictional double planet system orbiting Tau Ceti. The two planets are called Anarres and Urras.
- In Gene Roddenberry's Earth: Final Conflict, the warlike Jaridian species is referred to as having its main stronghold at Tau Ceti.
- In Alan Moore's Skizz, Interpreter Zhcchz from Tau Ceti crash-lands outside Birmingham.
- In C.J. Cherryh's Hugo Award-Winning novel Downbelow Station, Downbelow Station orbits a planet around Tau Ceti.
- In Julian May's Galactic Milieu trilogy, Tau Ceti is orbited by the planet Molakar, inhabited by the alien race Krondaku, and destroyed in the Metapsychic Rebellion
References
- Greaves, J. S. et al, "The debris disc around tau Ceti: a massive analogue to the Kuiper Belt", Monthly Notices of the Royal Astronomical Society, Volume 351, Issue 3, 07/2004.