Story perspectives

New Four-Planet System Defies Formation Theories, Astronomers Say

2/13/2026

Summary

Story summary

Astronomers have identified a four-planet system around the red dwarf star LHS 1903, 116 light-years from Earth.
The planets show a rocky-gaseous-gaseous-rocky sequence, challenging models that expect rocky planets to form closer to the star.
The study, published in Science from international collaboration using advanced telescopes, finds the outermost planet LHS 1903 e formed in a gas-depleted environment, accumulating little gas after the inner planets formed.

History

Historical Context

In 1992, astronomers Aleksander Wolszczan and Dale Frail discovered two terrestrial-mass planets orbiting the pulsar PSR B1257+12, marking the first confirmed detection of exoplanets. This groundbreaking method, based on pulsar timing, challenged existing theories of planetary formation. The recent identification of a four-planet system around LHS 1903 continues to reshape our understanding of planetary systems and the potential for extraterrestrial life.

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Story summary

Astronomers have identified a four-planet system around the red dwarf star LHS 1903, 116 light-years from Earth.
The planets show a rocky-gaseous-gaseous-rocky sequence, challenging models that expect rocky planets to form closer to the star.
The study, published in Science from international collaboration using advanced telescopes, finds the outermost planet LHS 1903 e formed in a gas-depleted environment, accumulating little gas after the inner planets formed.

1 / 2