Portal:Astronomy/Featured/June 2009



Tau Ceti (τ Cet / τ Ceti, ) is a star in the constellation Cetus that is similar to the Sun in mass and spectral type. At just under 12 light years' distance from the Solar System, it is a relatively close star. Tau Ceti is "metal-deficient" and so it is thought to be less likely to host rocky planets. Observations have detected more than 10 times as much dust surrounding Tau Ceti as is present in the Solar System. The star appears stable, with little stellar variation. (The image compares the Sun (left) with Tau Ceti (right) for a hypothetical observer at an equal distance to each star) No companions have yet been detected around Tau Ceti through astrometric or radial velocity measurements, but given current search refinement this only excludes substellar companions such as large brown dwarfs. Because of the debris disk, any planet orbiting Tau Ceti would face far more impact events than the Earth. Despite this hurdle to habitability, its "solar analog" (Sun-like) characteristics have led to widespread interest in the star. It has been consistently listed as a target for Search for Extra-Terrestrial Intelligence (SETI) searches, given its stability and similarity to the Sun, and it appears in some science fiction literature.

Tau Ceti does not have a widely recognized traditional name, as do many other prominent stars. It can be seen with the unaided eye as a faint third-magnitude star.

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