Tau Ceti f is a potential super-Earth[2] or mini-Neptune orbiting Tau Ceti that was discovered in 2012 by statistical analyses of the star's variations in radial velocity, based on data obtained using HIRES, AAPS, and HARPS.
[7] However, if it and its companion planets were similarly inclined to Tau Ceti's debris disk at 35±10°, f could 5.56+1.48−1.94 and 9.30+2.48−3.24 Earth masses, which means it's slightly more likely to be a mini-Neptune, although the exoplanet is included in the conservative sample of potentially habitable exoplanets.
[9] As of October 2020, Tau Ceti f is considered the most potentially habitable exoplanet orbiting a Sun-like star.
[10] Its neighbor, Tau Ceti e, was previously regarded as a potentially habitable exoplanet in the conservative sample, but it was determined to likely be too hot to hold life, more similar to Venus.
[11] It and its companion may suffer from a continuous bombardment of asteroids, up to 10 times higher than in the Solar System,[12] but a conjectured (super-)Jovian planet as outlined in a 2019 Astronomy & Astrophysics paper may be shepherding the disk, as it may be as close as 3 AU and as far away as 20.