YZ Ceti is a red dwarf star in the constellation Cetus.

The two are only about 1.6 light years apart,[11] a little more than a third of the distance from the Sun to the Solar System's nearest neighbor, Proxima Centauri.

YZ Ceti also shows small periodic variations in brightness caused by starspots or chromospheric features moving as the star rotates.

[9] On 10 August 2017 three planets were announced to have been discovered around YZ Ceti and a possible fourth sub-Earth planet candidate, still needing confirmation, with 0.472±0.096 Earth masses at an orbital period of 1.04 days.

[13] Two 2023 studies detected bursts of radiation in radio wavelengths from YZ Ceti, which is likely associated with interaction of the innermost planet, YZ Ceti b, with the star as well as evidence for the presence of magnetic fields.