Astronomers investigate unique exoplanet formation and atmospheric signals

Astronomers are investigating two distinct exoplanet phenomena that could reshape our understanding of planetary formation and habitability.

A study led by the University of Warwick suggests that the system HS 0209+0832 may contain a ‘second-generation’ planet. This hypothesis posits that the planet formed from material expelled by its host star after it died and transitioned into a white dwarf. Chemical evidence in the atmosphere, including zinc, copper, and niobium—elements found at levels over a thousand times higher than in the Sun—supports the idea of a ‘phoenix planet’ that has risen from the ashes of its predecessor.

Separately, researchers are studying LHS 1140b, an exoplanet located in the habitable zone of a red dwarf star in the Cetus constellation. Observations have indicated potential signs of helium escaping the planet's atmosphere. While not a direct sign of alien life, the presence of helium may suggest the existence of a stable secondary atmosphere, rather than a primary hydrogen-rich one. This distinction is crucial for determining if the planet could support liquid water and long-term geological or biological processes.