Tau Ceti

Tau Ceti is a star in the constellation Cetus, a border star linking the Republic Sector and the Cetian Sector, and is the star of the Cetian homeworld a’Mairuno-mot. It is very near to Sol and hence Earth, and is spectrally similar though metal-deficient and slightly cooler. It has one companion that is close but not gravitationally linked, a red dwarf named YZ Ceti, which is 1.6 LY from Tau Ceti.

In Earth's history, Tau Ceti was consistently listed as a target for the Search for Extra-Terrestrial Intelligence (SETI), and its inhabitants (the Cetians) were appropriately the first alien species to contact humanity.

The star has five planets, two in its habitable zone, and a large debris disk, which gives its planets a higher impact incidence than Sol's habitable worlds. A’Mairuno-mot's laser defense system is partly the result (and solution) of these impact events, as is its higher water content (seeded from comets and asteroids) and lower dry land mass.

Tau Ceti is typically the name both humans and Cetians outside Tau Ceti use in reference to both the star and homeworld of the Cetians, despite the fact that it is a name generated by mankind. The use of this shorthand is an oddity of Cetian culture, which generally does not take itself very seriously and is always working to make others more comfortable.