K2-398

Measured

Distance

about 1,980 light-years

Star's spectral type

G2

Confirmed planets

2

How far, from the Sun

About 1,980 light-years. To cross it:

• Light1,980 years
• Voyager 1's speed35.2 million years
• Driving at 100 km/h21.4 billion years

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 2022, by transit (NASA Exoplanet Archive).

Its planets

• K2-398 b — 2.3 times Earth's width, a 'sub-Neptune' — bigger than Earth, smaller than Neptune; its year lasts 6 days; found in 2022 by transit.
• K2-398 c — 5.1 times Earth's width, Neptune-sized; its year lasts 19 days; found in 2022 by transit.

Where this comes from

• 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.

Every catalogue Ouranos draws is credited on the credits page.