Astronomers may have found the missing link in the story of the Milky Way's most common planets.

In this SETI Live, host Moiya McTier is joined by exoplanet scientist John H. Livingston to explore a new discovery that helps connect the dots between small rocky worlds like Earth and the larger "sub-Neptunes" that dominate our galaxy.

Using cutting-edge observations and statistical analysis, researchers have identified a population of planets that appears to bridge a long-standing gap in our understanding of planetary formation. For years, astronomers have known that planets of sizes between Earth and Neptune are incredibly common—but their origins and evolutionary paths have remained puzzling. This new result may finally clarify how these worlds form, evolve, and sometimes transform.

What does this mean for:

• How do planetary systems assemble?

• Why does our Solar System look so unusual?

• The search for habitable worlds beyond Earth?

Join us as we break down the science, the methods, and the bigger implications for exoplanet research and the search for life.

Press release: https://www.abc-nins.jp/en/2026/01/08/10010/

Paper: https://www.nature.com/articles/s41586-025-09840-z

(Recorded live 26 February 2026.)