HD 219134 f is a super-Earth on a 22.7-day orbit around HD 219134, an orange dwarf star about 21 light-years away with up to six reported planets. Unlike its inner siblings HD 219134 b and c, it has never been seen crossing in front of its star, so only its minimum mass is known: about seven Earth masses, according to the NASA Exoplanet Archive.
It was reported in 2015 by a team led by Steven Vogt, who measured the star's wobble, the slight back-and-forth motion its planets' gravity gives it, with 175 measurements from the HIRES spectrograph at Keck Observatory and 101 from the Automated Planet Finder at Lick Observatory. They found six signals, at periods from 3.1 to 2,247 days, and the one at 22.8 days became HD 219134 f. Several years of precise brightness measurements showed the star's light to be almost perfectly steady, which supported planets rather than starspots as the cause of the signals. A separate team led by Fatemeh Motalebi, using the HARPS-N spectrograph the same year, independently found the inner planets.
The two teams' findings did not match exactly. Motalebi's team reported four planets and Vogt's six, and their outer planets differ, so the system's full makeup is still being worked out. HD 219134 f receives about 12 times the light Earth gets from the Sun, according to the archive, so it is too hot for liquid water. Its size is unknown; the radius listed in the archive is an estimate. A 2026 study of the star suggested that the planets farther out may still keep part of their original gas envelopes, unlike the stripped inner ones.