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Exoplanet · Ross 128

Ross 128 b

Orbit0.05 AU
Year9.87 days
Mass≥ 1.4 M⊕
Temperature~301 K (estimated)

It circles Ross 128 once every 9.87 days, 0.05 AU out: about 7.8 times closer than Mercury is to the Sun.

Found in 2017 by the radial velocity method, which measures the star's wobble. That gives a minimum mass, so it could be heavier.

Sources

  1. NASA Exoplanet Archive, Planetary Systems Composite Parameters (queried 28 Oct 2026)
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