Voyager 1 at the speed it moved outward over the year to 2026-10-25 (JPL Horizons). Driving: nonstop, never refuelling.
How it was found
First planet found in 2019, by transit (NASA Exoplanet Archive).
Its planets
HD 23472 e — 0.8 times Earth's width, about Earth-sized — probably rocky; its year lasts 8 days; about 450 °C, hotter than boiling water; found in 2022 by transit.
HD 23472 c — 1.9 times Earth's width, a 'sub-Neptune' — bigger than Earth, smaller than Neptune; its year lasts 30 days; about 190 °C, hotter than boiling water; found in 2019 by transit.
HD 23472 b — 2 times Earth's width, a 'sub-Neptune' — bigger than Earth, smaller than Neptune; its year lasts 18 days; about 270 °C, hotter than boiling water; found in 2019 by transit.
HD 23472 f — 1.1 times Earth's width, about Earth-sized — probably rocky; its year lasts 12 days; about 360 °C, hotter than boiling water; found in 2022 by transit.
HD 23472 d — 0.8 times Earth's width, smaller than the Earth; its year lasts 4 days; about 640 °C, hotter than boiling water; found in 2022 by transit.
NASA Exoplanet Archive, Planetary Systems Composite Parameters (fetched 2026-11-02). Composite values: where a planet's size or mass was not measured, the archive estimates it from the other.
This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with NASA under the Exoplanet Exploration Program.